Collaboration - Swerea · systems. CEOCOR brings together specialists from universities, research centres, ... Support to SME’s within the surface finishing industry 21 ... this

SUCCESS STORIES NEW EQUIPMENT SEMINARS

# 8 March2015

Collaborationwith Millbrook automotive test facility

Effects of stray currents

Carbon-fibre-reinforced polymers in road environ-ments

W E L C O M E T OI N T E R N A T I O N A L C O N G R E S S A N D E X H I B I T I O N

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CEOCOR, founded in 1956, is an international scientific non-profit association dealing with corrosion and protection of pipes and pipeline systems.

CEOCOR brings together specialists from universities, research centres,

institutes and companies within:

• water, gas and oil distribution

• waste water collecting and treatment

• pipe producers and manufactures and equipment for cathodic protection systems

The congress consists of about 40 presentations, over two days, as well as an exhibition. www.ceocor.eu

STOCKHOLM 2 – 5 J U N E 2 0 1 5

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WELCOME TO

CEOCOR 2015INTERNATIONAL CONGRESS AND EXHIBITION

Editors: Tomas Hult, [email protected] Margaretha Sönnergaard, [email protected]

Advisory Board: Eva Johansson, Eva Lind-Ulmgren,Bertil Sandberg, Johan Tidblad, Dominique Thierry.

Printing: EO GrafiskaCover: The Millbrook Proving Ground in England.

Corrosion News is published by: Swerea KIMAB, Sweden and Institut de la Corrosion, France

Subscriptions: Swerea KIMAB Corrosion News PO-Box 7047SE-164 07 Kista, Sweden [email protected] www.swereakimab.se

Corrosion News All rights reserved. No part of this publication may be reproduced in any form by any electronic or mechanical means without permission in writing from Swerea KIMAB.

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New methods or assessing environmentally hazardous wrecks 4

New JIP-project – Focus on corrosion and mechanical properties in multi material designs 7

Collaboration with automotive test facility 8

Nondestructive testing prevents accidents 10

Carbon-fibre-reinforced polymers in road environments 12

Hello there Jessica Andersson 15

Effects of stray currents 16

Millions to be saved with the right surface protection 20

Support to SME’s within the surface finishing industry 21

Bimetallic corrosion under atmospheric conditions – field exposure tests 22

MUSECORR, one of Horizon 2020’s success stories 22

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Due to a new analysis tool it is now easier to identify which of the many wrecks in Swedish coastal waters pose a threat to the environment

Over the last few months Swerea KIMAB has worked to develop a col-laborative relationship with Millbrook Proving Ground Ltd. in England.

Interest in carbon-fibre-reinforced polymers within the vehicle indus-try continues to grow, since substi-tute components can contribute to reduced vehicle weight.

Swerea KIMAB have, together with SKB, studied the effects of stray currents on the corrosion of copper canisters in the planned repository for nuclear waste at Forsmark.

CORROSION NEWS # 8 | 20154

It is now easier to identify which of the many wrecks in Swedish coastal waters pose a threat to the environment and must therefore be decon-taminated. This is due to a new analysis tool called VRAKA, and a more consist-ent model for organizing work and sharing responsibility.

TEXT: JOHAN HÅRD, HARDAORD.SE

THERE ARE SOME 20,000 known wrecks in the coastal waters of Sweden. Unfor-tunately, of these many wrecks some pose a threat to the environment due to the cargo and the amount of fuel they were carrying when they sank. The problem is knowing exacting which wrecks are most in need of corrective measures.

As in so many other cases, the villain is corrosion. When the sunken vessels rust and break up, both the cargo holds and fuel tanks can begin to leak.

– An important factor in this context is the rate at which a wreck corrodes, says Ulf Sender, corrosion specialist at Swerea KIMAB.

THE CORROSION RATE of carbon steel in seawater is normally about 0.1 millime-tres per year.

– However, with a wreck that is partially submerged in sediment, as-sessing the corrosion rate can be more problematic, explains Ulf Sender. For example, oxygen content and salinity, the nature of the sediment and whether the steel is in contact with other metals are factors which can considerably has-ten the rate of corrosion locally.

The majority of the wrecks do not to pose any significant environmental haz-ard and can be allowed to remain where they are and break up.

A STUDY to determine which wrecks constitute an environmental hazard began during 2014. Swerea KIMAB has participated as one of the expert groups in the survey, which has been led by the Swedish Maritime Administra-tion. Other participants have included Chalmers University of Technology, the

New methods for assessing environmentally hazardous wrecks

CORROSION NEWS # 8 | 2015 5

Swedish Defence Research Agency, the Swedish Agency for Marine and Water Management, the Swedish Coast Guard and the National Maritime Museums.

The survey has identified 31 wrecks that are of particular interest. Of these, four have been subjected to closer examination, all of which lie at depths of between 18 and 74 metres.

The wrecks have been studied via hy-drographic survey and with the help of divers and remotely operated vehicles, to determine whether they can have any impact on the marine environment.

ANOTHER AIM HAS been to identify pos-sible means of managing wrecks that

may pose an environmental threat in the future.

Previous decontamination efforts have shown that it is often better and more cost effective to empty wrecks before they begin to leak, instead of adopting a wait-and-see approach. However, emptying a wreck is costly and is therefore not always the first course of action. Another problem is to determine which wrecks should be given priority. Therefore, what is needed is a consistent model for organizing work and sharing responsibility for inspection and inventory of environ-mentally hazardous wrecks.

Now, a new model for risk analysis

has been developed at Chalmers Uni-versity of Technology in Gothenburg. The model, called VRAKA, can be used to calculate the probability of a wreck beginning to leak.

The method is based on ISO stand-ards and covers considerably more parameters than the methods that are currently used. Consideration is given to both materials-science-related fac-tors and conditions in the surrounding environment, and, of course, to which types of environmentally hazardous substances, such as oils, that may be in the wreck.

VRAKA should be ready for use later in 2015.


FOUR WRECKS THAT WILL BE INSPECTED

ALTNESLies in the Kattegatt, between Anholt and Falkenberg. Collided with another freighter, east of Anholt in January 1988.The vessel is believed to have been carrying an estimated 30 cubic metres of bunker oil, about 3 cubic metres of engine oil and some 10-15 tonnes of marine gas oil. Some 20-22 cubic metres of the oil is believed to have been salvaged.

SKYTTERENLies in the Skagerrak, west of Måseskär. A so-called kvarstad vessel that was

carrying, among other cargo, defence materiel during the Second World War. The ship was scuppered by its crew after being bombarded by a German battleship. The volume of oil on-board is not known, but oil has been seen on the surface of the sea in the vicinity of the wreck.

THETISLies in the Skagerrak, north of Smögen. A former marine survey vessel, Thetis was later used as a fishing vessel. The ship capsized and sank in October 1985. Records indicate that the ship may have

been carrying 17 cubic metres of fuel when she sank.

VILLONLies in the southern Baltic, east of Sim-rishamn. A freighter that sank in heavy seas in 1985 due to cargo shifting. The vessel is believed to have been carrying 4 cubic metres of fuel oil and 150 litres of engine oil.

Additionally, ownership and responsi-bility of the wrecks can cause problems. Often, it may be difficult to ascertain ownership and insurance conditions and consequently, who is responsible if the wreck begins to leak. If the wreck has lain on the seabed for a long time, it may be virtually impossible to deter-mine who is responsible. In Sweden, legal responsibility usually lies with the wreck’s owner.

But in cases of this type, where the wreck is old and ownership is uncer-tain, the Swedish state will likely have to assume the main responsibility and cost for preventing environmental contami-nation.

THE SWEDISH AGENCY for Marine and Water Management, HaV, may bear the main responsibility for risk analysis and decontamination of environmen-

tally hazardous wrecks. HaV may even collaborate with other authorities to perform mapping and hydrographic survey, sampling and other measures.

One advantage of collective responsi-bility may be that it is easier to com-pile important information about the sunken vessels. This may include insurance details, the location of the wreck, information about the cargo, the owner, the design of the vessel, etc. If this information is distributed in differ-

ent archives, it is difficult to gain a clear overview.

THE RESULTS have been presented to the government and it is hoped that this work will facilitate a decision on monitoring and decontamination of environmentally hazardous wrecks in the future.

Contact Ulf Sender, [email protected]


CARBON FIBER REINFORCED POLYMERS in multi material designs is of high interest within the automotive industry, because of the potential to reduce weight and fuel consumption of the vehicles. The density of CFRP material is approxi-mately 25 % of the density of steel and CFRP materials also have the benefit of a very high strength- to-weight ratio. Intensive work is ongoing to look into the possibilities to replace both struc-tural parts and components of the car body of steel with CFRP materials. Still, more knowledge is required before a more extensive replacement of steel can be carried out within the automotive industry. New materials need tailored assembling techniques and further investigations of the corrosion perfor-mance and the mechanical properties of these joined materials are needed. Carbon fibers are excellent cathodes and caution must be taken when joining CFRP with other automotive materials. Therefore, the assessment of the corro-sion and mechanical properties of joints are of great importance for the selection of durable joining techniques and mate-rial combinations.

WITH THIS background Swerea KIMAB and Insitut de la Corrosion have started a new project together called “Cor-

rosion and mechanical properties of joined and mixed materials including Carbon Fiber Reinforced Polymers”. The study is a joint industrial financed project with 14 participating companies from the automotive industry.

THE AIM of the study is to assess the cor-rosion performance of joined materi-als including CFRP material on their mechanical durability based both on ac-celerated tests and on mobile exposures on vehicles in service. Furthermore to evaluate the effect of simultaneous fatigue-corrosion in accelerated corro-sion test and to assess the degradation of the CFRP material in multi material designs.

A KICK-OFF meeting was held in Paris on February 5, 2015 in which the detailed project plan was determined. In total more than 30 material combinations and joining techniques will be investi-gated in accelerated corrosion tests and by mobile exposures on trailers. The duration of the project will be 3 years.

ContactBo Rendahl,

[email protected]

Nathalie LeBozec,

[email protected]

Einar Mattsson Award 2014 to Bo Rendahl

BO RENDAHL, research leader at Swerea KIMAB, has been awarded the 2014 Einar Mattsson Award in recognition of his world-leading expertise in the field of vehicle cor-rosion.

Over several years Bo has devel-oped a very successful concept for worldwide mobile exposure and benchmarking of design solutions with respect to corrosivity. The de-velopment of this research area has taken place in close collaboration with our colleagues at Institut de la Corrosion.

The members’ programme serves a recurring customer base that includes vehicle manufacturers and materials suppliers from throughout the world.

ContactBo Rendahl, [email protected]

NEW JIP-PROJECT

Focus on corrosion and mechanical properties in multi material designs

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AT ITS PROVING GROUND in the UK, Mill-brook has 70km of varied test tracks, in-cluding hill routes, high speed areas and challenging off road courses. Its profes-sional drivers and engineers perform repeatable tests on all types of vehicles in a secure and safe environment. It has a range of test facilities including engine dynamometers, environmental cham-bers, a crash laboratory and advanced emissions chassis dynamometers.

The purpose of Swerea KIMAB’s col-laboration with Millbrook is to develop corrosion tests for vehicles that take

place in a controlled environment, which is a capability some of our customers have enquired about. Millbrook already offers whole vehicle corrosion testing to its clients, but through this collabora-tion it has been possible to enhance the level of control of the test process and improve the understanding of how data gathered correlates to different materials exposed in various global regions.

Ed Rutherford, durablity manager at Millbrook explains:

– Working together with our partner in Sweden, we aim to increase Mill-

brook’s breadth of knowledge and skills in corrosion testing. In order to develop the expertise of our engineers we have enrolled on Swerea KIMAB’s corrosion awareness course and have joined the MRC Automotive.

WE LOOK forward to the many exciting potential projects that this collaboration will bring to both companies.

ContactBo Rendahl, [email protected] Gordon, [email protected]

Collaboration with automotive test facility

Over the last few months Swerea KIMAB has worked to develop a collaborative relationship with Millbrook Proving Ground Ltd. in England. Millbrook is a leading provider of a comprehensive range of vehicle test, validation and engineering services.

www.millbrook.co.uk

9CORROSION NEWS # 8 | 2015


Nondestructive testing prevents accidentsGlass-fibre-reinforced plastic (GFRP) is used in vessels for storing and handling corrosive fluids. A damaged vessel could therefore lead to a serious accident. Representatives of the plastics and composites industry are therefore calling for better methods for discovering damage and clear guide-lines for how defects should be interpreted. A step in the right direction is the so-called damage atlas that is now being created within the Värmeforsk plastics project.

– MANY PEOPLE are a bit careless, since they accept damage in plastic pressure vessels and pipes that would never be tolerated if it occurred in metal objects, says Pernilla Utterström at Inspecta. That the level of tolerance for defects in plastic objects is higher is often a result of unclear rules, lack of knowledge and difficulties in discovering defects in plastic materials.

– Compliance with industry stand-ards must be more stringent. The rules, regulations and standards that apply to metal objects also apply to objects made of plastic. For pressure vessels to be safe, the requirements in PED (the Pressure Equipment Directive) must be fol-lowed, says Carolina Ankerfors, Swerea KIMAB. Carolina manages the plastics project that Inspecta and Swerea KIMAB are working on and which has been commissioned by Värmeforsk.

Last autumn, to gather experience, lnspecta and Swerea KIMAB arranged a workshop on nondestructive test-ing (NDT) to which plastic engineers, manufacturers, owners and users of plastic and GFRP products, third-party organizations and materials specialists were invited.

ONE OF THE PARTICIPANTS was Pamela Henderson, materials specialist in the thermal power group at Vattenfall. She agrees that, unlike NDT of metals, NDT of plastics is in many cases lagging behind, and feels that there should be greater consensus within the industry.

– We need to discuss our experiences and be better at interpreting the signs of damage that we find. Incorrect interpre-tation can be very expensive.

HANS JÄRNBERG, BilIerud Korsnäs in Gävle, agrees.

– I work hands-on with plastic prod-ucts, so I am well aware of the problems we actually face in the industry. We need more knowledge about the rele-vant indications of defects and of which remedial measures we should take. Is the damage serious, or how should we interpret what we see?

KARIN JACOBSON, research manager at Swerea KIMAB, adds,

– We can find defects with NDT but, even with the help of NDT, we can never say for certain that there are no defects. The methods for testing plastic materials are not that reliable.

A ‘damage atlas’ of the most common defects could simplify assessment of damage in plastic objects.

NONDESTRUCTIVE TESTING is a require-ment according to the directives, but the NDT methods work best for metallic materials and have limitations with respect to testing of plastics and composites. The available alternatives include hardness testing, moisture content measurement, digital x-ray, ultrasound testing, microwave, infrared and visual inspection.

The new microwave technology requires only access to one side of the object. The method works well for identifying defects and measuring the thickness of plastic materials.

ANOTHER PROMISING, but costly, technique is thermography, which is suitable for detecting material thickness in plastic objects. Ultrasound is a rapid method, but the object must have two flat, parallel surfaces. Digital x-ray, on the other hand, does not.

– Certain plastic are somewhat trans-parent. By illuminating the object both from the outside and the inside, you can



EUROPEAN FEDERATION OF CORROSION

THE VÄRMEFORSK PLASTICS PROJECT

The project will result in a damage atlas and lead to an industry-wide approach to assessing damage, as well as improved methods for non-destructive testing of plastics and composites. The project is a joint venture involving Swerea KIMAB, Inspecta, Bodens Energi and TER-MAP. Caroline Ankerfors, research engineer at Swerea KIMAB, is the project manager.

see quite a lot, says Pernilla Utterström, pointing out that all methods have their advantages and disadvantages. There-fore, what is required is a combination of several methods to gain a representa-tive image of the object’s status.

These methods can show a lot, but cannot reveal the full extent of the defects or damage. The technician inspecting the object must also have a good know ledge of the material, be able to interpret the signals and know what they are looking for.

– The focus must therefore be placed on developing instruments for visual in-spection and interpreting what we see. In the plastics project we are develop-ing a ‘damage atlas’, and taking a closer look at commonly occurring defects to enable a tool that can be used to inspect and assess damage in plastic objects, concludes Pernilla Utterström.

THE PROJECT is expected to conclude during the latter half of 2015. In the spring a third workshop will be ar-ranged, with focus on the damage atlas – an easily accessible aid in the form of a handbook for assessing GFRP structures.

ContactKarin Jacobson, [email protected]

Docent in Atmos pheric CorrosionJOHAN TIDBLAD was appointed Docent in Corrosion Science, with specializa-tion in Atmospheric Corrosion, at KTH in Stockholm in January 2015. Johan’s Docent lecture was entitled Planning for a sustainable infrastructure with short-term corrosion testing. Can we solve the conflicting demands of the modern world?

Johan works at Swerea KIMAB as man-ager for the Corrosion Protection and Surface Engineering section.

ContactJohan Tidblad, [email protected]


CORROSION NEWS # 8 | 201512 CORROSION NEWS # 8 | 201512


ROADS ARE AN aggressive environment for CFRP, since factors such as moisture and humidity, temperature differences and salt contribute to degradation of the polymer matrix. Another challenge is galvanic coupling, where there is

the risk of galvanic corrosion in joints, where carbon fibre is more noble (i.e., less active) than most metals in the galvanic series, meaning that the metal corrodes in contact with carbon fibre.

IN THIS PROJECT, DEGRADATION and cor-rosion mechanisms of CFRP and CFRP/metal bonds are studied. The first sec-tion of the project addresses moisture-induced degradation at the interfaces within the composite; the second deals with corrosion mechanisms for CRFP/metal bonds in road environments, and the third has to do with a service-life analysis performed via mechani-cal modelling in combination with data from the first two sections of the project.

To investigate the effects of moisture uptake in different environments, CFRP has been exposed under different condi-

CRFP ROAD

Carbon-fibre- reinforced polymers in road environments

Interest in carbon-fibre-reinforced polymers (CFRP) within the vehicle industry continues to grow, since substitute components can contribute to reduced vehicle weight without jeopardizing performance. This bodes well for the heavy-vehicle industry, where there are demands for great-er transport efficiency, but also for the passenger vehicle sector, where environmental requirements for reduced carbon dioxide emissions must be met.

DMA, dynamic mechanical analysis: Dynamic mechanical load under heating.



One example concerns variation in water uptake depending on environment.

Another object of study is how galvanic coupling affects the composite after exposure.

tions of salinity (varying water activity), humidity and different temperatures, as well as exposure in a freeze-thaw cycle. This means that, among other things, we can study the mechanisms and transport of water uptake, as well as chemical and physical changes induced by water, and the degradation processes at the interface between fibre and ma-trix within the composite.

In the galvanic studies the aim is to determine, among other things, the corrosion rates of CFRP galvanically coupled to various metals, the molecu-lar mechanisms that occur in galvanic coupling and oxygen reduction on carbon fibre on the composite. Galvani-cally coupled CFRP has been exposed

in the field and in accelerated corrosion testing. Electrochemical experiment will also be conducted. Methods used for analyses and characterization in-clude Photoacoustic Fourier transform infrared spectroscopy (FTIR-PAS), FTIR Spectroscopy: Attenuated Total Reflectance (ATR), Near-infrared FTIR, FTIR-Microscopy, Electrochemical impedance spectroscopy (EIS), poten-tial measurements, potentiodynamic measurements, Dynamic Mechanical Analysis (DMA) and Scanning Electron Microscopy (SEM).

DATA FROM the different analyses do not provide complete results; instead, a combination of the various analysis

techniques and data enable a better overall understanding of the mecha-nisms of degradation and corrosion.

With FTIR-PAS and Near IR, we can obtain information about water in the composite and how it is bonded to the matrix. DMA is used to determine the storage/loss modulus, but also gives in-dications as to whether chemical chang-es have taken place in the composite. SEM is used to study delamination and interfaces between the fibres and ma-trix. The electrochemical measurements are made to see how the composite is influenced by galvanic couplings to dif-ferent metals and to analyze the effect of the oxygen reduction in the composite. Many of the above-mentioned methods have been developed or adapted for use with CFRP. In-situ trials with galvani-cally coupled fibres that have been ex-posed in controlled environments will be performed, such that changes within the composite can be observed in real time via FTIR.

MECHANISM STUDIES, characterizations and analyses; Scania, which is providing accelerated testing, in-field expo-sures and mechanical testing; Swerea SICOMP, which has made the compos-ite and is performing computations and modelling of strength and service life, and Audi.

ContactJessica Andersson, [email protected] measurements


Hello there...

... Jessica Andersson, who is working with a research project entitled “CRFP road – carbon-fibre-reinforced polymers in road environments”.

What’s it all about?– We are investigating how a composite material made from polymers and carbon fibre (CFRP) reacts to corrosive factors in road environments. This is a joint project involving vehicle manufac-turers Scania and Audi, KTH (the Royal Institute of Technology in Stockholm), Swerea KIMAB and Swerea SICOMP. It is also part of my doctoral work at the Division of Surface and Corrosion Science at KTH.

Ultimately, the material will be used in the vehicle industry to build lighter cars.

What makes the project especially interesting is that, while academic in nature, it involves both basic research and applied research.

What is the biggest question?– Similar material is used in the aerospace indus-try. But road environments are more aggressive. A lot of factors affect the material: water, salt, mois-ture and humidity, temperature – and strength on impact. In aerospace, these factors are a lot more predictable. What we are attempting to under-stand is how the material reacts, and why.

How far have you come with the project?– We are about halfway through. It consists of three parts. First, we are looking at water uptake and how the material is affected by salt and different temperatures. In field studies, we have mounted the material on vehicles. In the labora-tory we are working with accelerated corrosion. Something that is of particular interest is what happens in the bond between metal and compos-ite. Here, processes occur that can affect both the metal and the carbon fibre.

In the second part of the project we are study-ing corrosion mechanisms with electrochemical and other advanced analysis methods. The aim is to be able to predict how the material will corrode in a road environment.

In the final part of the project we will integrate material data from the road environment and cor-rosion testing in SICOMP’s computation models. Ultimately, the aim is to be able to predict service

life and resistance to exposure, so as to be able to dimension the material during design.

We will present the final report next year. But we hope to be able to deliver a progress report this year. And we have sent a summary to the Eu-rocorr 2015 congress in Austria, where we hope to present the results.

Is there a lot of interest in this type of material in the vehicle industry?– Huge interest. In principle, all manufacturers are looking for solutions for building lighter vehicles. The fact that we are collaborating closely with major vehicle manufacturers such as Scania and Audi shows that this is really interesting.

ContactJessica Andersson, [email protected]

CORROSION NEWS # 8 | 201516 CORROSION NEWS # 8 | 201516


In HVDC (High Voltage DC power transmissions) thousands of amperes are intentionally fed into the ground at one site and collected at another remote site. Over large distances the ground actually has lower resistance than a ca-ble. New HVDC installations are almost exclusively bi-polar (with two cables) so that the current in one direction is

Effects of stray currents

Swerea KIMAB have, together with SKB (Swedish Nuclear Fuel and Waste Management) studied the effects of stray currents on the corrosion of copper canisters in the planned repository for spent nuclear fuel at Forsmark. Electrical currents in the ground and bedrock can come from many sources, but the highest corrosion effect from such can be expected from HVDC installations.

Figure 2. The extent of the planned respository, 500 m below ground.

cancelled or nearly cancelled by a cur-rent in the opposite direction. However, most bi-polar HVDC installations can also operate in mono-polar mode.

The repositoryThe planned repository is located near Forsmark power plant, figure 1. A tunnel system approximately 2x2 km will be exca-

Figure 1. The repository will be located near Forsmark. The red dot show the location of the electrode (original anode) for the existing Fenno-Skan power transmission, now operating in bi-polar mode. The corresponding electrode (original cathode) for the Fenno-Skan is located in Finland.

vated 500 m below ground, figure 2. The 5 m long copper canisters will be placed vertically in deposition holes 6 m apart, figure 3. Figure 4, with details of the depo-sition holes, shows that these are much larger than the copper canisters. The excess volume will be filled with highly compacted bentonite that, under uptake of water, will swell around the canister.

To the left Forsmark nuclear power plant. It’s one of the largest power plants in Sweden, situated on the east coast of Sweden.


Closing of the repositoryAt closure of the repository, the whole tunnel system, at repository level, will be filled with bentonite clay. The lower part of the various shafts and the ramp that connect reposi-tory level with ground level will also be filled with bentonite. When saturated by the ground water the bentonite swells and forms a dense mass. However, this swelling process may be quite slow and it may take thousands of years to reach full saturation, particularly for the compacted bentonite in the deposition holes. The electrical conductivity of the bentonite is highly dependent on the water content.

Location of a future HVDC transmissionIt is of course not possible to predict the location of future HVDC installations. Technology and economy of operation however, indicate that any future HVDC electrode will be located off-shore. The relatively high resistivity of the bedrock in the Forsmark region would cause a land based electrode to give unacceptable interference with infrastructure and would be associated with high power loss. As a borderline accept-able location of a future HVDC electrode, a site 2 km from the shore has been studied. The average slope of the seabed outside Forsmark is approximated as constant with an angle of 1 m/1000 m so the depth at the site of the future electrode would be 2 m.

The Fenno-Skan electrodeThe electrode for the existing HVDC transmission, Fenno-skan, is located about 2.3 km from shore but the local depth at the site of the electrode is greater than the average slope of 1 m/1000 m would predict.

Corrosion from oxygen, sulfides and electrical fieldsExisting estimates of canister corrosion are based on available amounts and diffusion rates of oxygen and of sulfides. The procedure applied here aims at calculating the corrosion rate that can be attributed to various electrical fields. These calcu-lated rates should be added to the existing estimates to obtain the total corrosion as function of time.

Figure 5. A representation of a possible future situation where the sea, shown as a colored disc, covers the entire repository. The boundaries of the hemisphere indicate the boundaries of the FEM-model. The boundary condition for the calculation is that the boundary constitutes an isopotential surface.

ProcedureA Finite Element Model (FEM) representation of the reposi-tory or a small part of the repository is subjected to various electrical fields, figure 5. Relatively large parts of the bedrock are included in the model volume. The resistivity of the bedrock in the Forsmark region has previously been charted. Six different, alternative, resistivity functions for the bedrock were studied to allow for uncertainties in the actual values, figure 6.

Figure 4. Planned dimensions of the deposition hole and the cross sec-tion of a deposition tunnel. A canister is schematically depicted to the right.

Figure 3. A deposition tunnel branching from a main tunnel. Copper canisters will be deposited in the deposition holes, 6 m apart.


REFERENCES

Possible influence from stray currents from high volt-age DC power transmission on copper canisters. Claes Taxén, Bertil Sandberg, Swerea KIMAB, Christina Lilja, Svensk Kärnbränslehantering. Technical Report TR-14-15. Svensk Kärnbränslehantering AB 2014.

Figure 6. Alternative resistivity functions for the bedrock. Corrosion effects are calculated for each of six functions, in order to allow for uncertainties and geological changes.

The future HVDC electrodeJust as with the location of a future electrode, it is not possible to predict the design of the electrode. But technology and economy give some boundaries. The model HVDC electrode is capable of continuously delivering 2500 A in mono-polar mode, it is designed as a ring with a radius of 100 m, figure 7. For comparison, the Fenno-skan 2 cable is designed for 1670 A but together with Fenno-skan 1, running 1360 A in the opposite direction the net current is much lower.

The future coast lineWhen several glacial cycles are considered it is possible that the Baltic Sea may extend in over the location of the reposi-tory during some periods. During such periods, a HVDC

Figure 7. The HVDC electrode represented as a ring of sub-electrodes, in red, located directly on top of the model shaft in the model repository. Details from figure 5.

electrode may conceivably be located directly on top of the repository. This situation was found to cause the highest cor-rosion effects on the copper canisters.

Corrosion analysisWhen only the tunnel system is considered and not the depo-sition holes, the voltage between the positions of the upper and lower ends of a deposition hole would be quite high, up to 40 V. However, when the highly conductive bentonite clay that surrounds the canister is introduced, this voltage drops sharply. The resulting voltage between the top end and the lower end of a canister would be about 0.4 V for the most exposed canister. Applying an experimentally determined polarization resistance for copper in bentonite, an increased corrosion rate of about 0.2 µm/year is predicted for the period with the HVDC electrode installed. Localised corro-sion (pitting) of copper is not predicted, as the chemistry of the bentonite and groundwater does not allow the formation of partially protective scales of corrosion products that could breakdown to give high local corrosion rates (i.e. pitting).

The situation todayA local field strength of about 1.5 V/km has been observed close to Forsmark Power station. This field strength is most probably an effect of the groundings at Formark power plant together with the remote electrical field from Fenno-Skan. The resulting voltage between the top end and the lower end of a canister is calculated to be about 0.008 V for the case when the bentonite has the same water content as at deposition. In terms of corrosion, the increase in the rate is estimated to be about 0.003 μm/year.

Contact Claes Taxén, [email protected]


DURING THE two-day event, suppliers, inspectors, buyers and consultants gathered to exchange experiences and share their views on the latest in legisla-tion and regulations, equipment and technology.

– The conference has doubled in size in just four years, but many people who could benefit from knowledge con-cerning surface protection have yet to

attend, explained Peter Olofsson, editor in chief of the trade paper Underhåll och Driftsäkerhet.

BY PROTECTING the surfaces of metal and concrete, Swedish companies and municipal authorities can prolong the service life of everything from buildings to sewage systems and industrial equip-ment. Each year, Ytskydd – Surface Protection – provide a meeting place for gathering expertise and making new contacts.

– If we are to ensure good surface protection, we must adopt a broader approach and work more together. This includes engineering specialists, manufacturers, consultants, buyers, research institutes and inspectors, said Tommy Thörn from Ytskyddsgruppen, the Surface Protection group.

NEW FOR THIS year were the industry-oriented niche seminars on bridges/harbours, waste management plants, combined powered and heating/district heating plants and more. In all, the conference offered indepth seminars and discussions in 13 different areas. In many of the seminars, examples of reference objects that are 15 to 20 years old were presented, thereby giving in-sights into both technical and economic aspects and functions.

As a co-organiser of Ytskydd 2015, Swerea KIMAB was on hand together with the industry organization Auk-

Millions to be saved with the right surface protectionYTSKYDD 2015 (SURFACE PROTECTION 2015) IS A STEP IN THE RIGHT DIRECTION

Ytskydd 2015 (4-5 February in Gothenburg, Sweden) attracted more than 290 surface-protection professionals from Sweden and neighbouring Nordic countries.

FACTS

Ytskydd, the Nordic region’s biggest conference on surface protection, is arranged by the trade paper Underhåll & Driftsäkerhet, Swerea Kimab and CBI Betonginstitutet in collaboration with Ytskyddsgrup-pen and Underhållsmässan. 2015 is the fifth year for Ytskydd. Read more at: www.ytskydd.com

torisationen för Rostskyddsmålning, to present a highly anticipated new book, a guide to rust prevention. The new edi-tion, the first since 1999, has been both updated and augmented. The aim has been to create a handbook that provides an overview of a very complex area. A new section in the form of a glossary has been added.

– It is important that we speak the same language, explains Charlotte Pers-son, coordinator for the project.

DURING THE CONFERENCE, the “Sur-face Protector of the Year” award was presented to two winners in recogni-tion of their efforts in this area; namely, Borås Stad Servicekontor and Karlskoga Energi.


OUR EXTENSIVE hands-on experience with equipment and components used in the chemical industry, paper & pulp and energy sectors has been achieved through many years of work for the MRC and individual customers. For in-stance, in a current European project a lot of work has also been done to study polymers used in the steel pickling industry.

In a recently started project aimed towards small and medium sized enter-prises (SME’s), Swerea KIMAB plan to map and support the surface finishing (plating) industry. These companies supply products to the automotive, building and water and sanitation in-dustries as well as to furniture and door industries. Typical products are iron and aluminium which have been nickel, chromium or zinc plated or chemi-cally oxidized, for instance anodized aluminium.

THE MAPPING PART of the project aims to find out if there are any special problems with plastic or rubber process equipment such as pipes, tanks, baths, pumps, valves, fixtures etc. If there are problems found, in which kind of chemical environments (processes) do problems occur and to what extent?

This identification and quantification shall be done by close cooperation with the companies and dialogue with managers and maintenance staff. The mapping part of the project is led by Svante Nordänger.

After identification and quantification Swerea KIMAB can offer the SME’s fur-ther help and deliver proposals of how to solve the company-specific problems (this is a second step, outside of this project). This problem solving can be done individually for the company or be performed as a group project, where companies with similar problems could possibly receive some financial sup-port from national funds. With group projects such as this, a network between companies with similar problems can be created which often leads to beneficial collaboration on industry-specific issues between parties.

THROUGH VISITS to SME’s Swerea KIMAB also have an opportunity to present how we work and how we can support businesses in other areas utilis-ing our facilities, lab equipment and industrial networks.

ContactSvante Nordänger, [email protected]

Support to SME’s within the surface finishing industry

DAVID LINDELL de-fended his doctoral thesis in February 2015 at the School of Chemical Science and Engineering, Di-vision of Surface and Corrosion Science at KTH. David’s thesis is entitled Process-microstructure corrosion interrelations for stainless steel. The aim of the work has been to understand various aspects of the annealing process in order to find new combinations of microstructural properties for stainless steels. Much of the work has been devoted to laboratory and pilot-scale simulations of annealing, as well as quantitative metallography with the help of elec-tron backscatter diffraction (EBSD).

David is senior researcher in the Materials Engineering section at Swerea KIMAB.

ContactDavid Lindell, [email protected]

JOHAN AHLSTRÖM

has presented his Licentiate thesis at the Division of Build-ing Materials, Lund University, Faculty of Engineering. His the-sis, entitled Corrosion of steel in concrete at various moisture and chloride levels, includes a laboratory study and a field study. In the laboratory study, Johan measured the corrosion rate of steel in concrete at varying moisture and chloride levels. In the field study, he assessed the galvanic corrosion prop-erties of steel exposed to concrete in a cooling water tunnel.

Johan is research engineer in the Corrosion protection & Surface tech-nology section at Swerea KIMAB.

ContactJohan Ahlström, [email protected]

The Polymers in Corrosive Environments department within Swerea KIMAB has a deep knowledge and understanding regarding the behaviour of plastic and rubber materials for process equipment in different corrosive environments.


TO PROTECT Europe’s cultural heritage artefacts from the ravages of corrosion, sensitive detectors have been developed that monitor corrosive atmospheric pol-lutants in museums and archives. The detectors issue a warning signal when preventive measures must be taken. The project has achieved great commercial success. This has also resulted in follow-up research on new applications for the sensor in areas including vehicle corro-sion and the paper industry.

INSTITUT DE LA CORROSION (Swerea KIMAB’s subsidiary in France) is the coordinator.

ContactTomas Prosek, [email protected]

IN THE SUGGESTED revision of the ISO-standard for the determination of bimetallic corrosion in atmospheric exposure corrosion tests*, three types of specimens for measuring bimetallic corrosion are described. In this work performance of these specimen types are compared.

After one year atmospheric field exposure, corrosion of the anodic member of each couple has been deter-mined as mass loss and the bimetallic effect b calculated as b = (rtest – rref)/(rtest + rref) where rtest is corrosion rate for the anodic member of the couple in contact with another metal and rref is the corrosion rate in contact with a plate/washer of the same metal or, for wire-on-bolt specimens, in contact with a nylon screw.

Exposure sites, specimen types, and calculated bimetallic effects for selectedmaterial combinations are shown in the table.

FROM THE CORROSION rates measured, the specimen types were found to differ in sensitivity, wire-on-bolt type speci-mens, with the whole anode area close to the cathode being the most sensitive and the rectangular type specimens showing the lowest sensitivity due to the relatively larger anode size. About the same bimetallic effect was found for the washer and wire-on-bolt type specimens while lower bimetallic effect was calculated for the rectangular plates as a result of the lower sensitivity. A

disadvantage with wire-on-bolt type specimens is that all materials cannot be obtained as wires and that corroded wires may break, which mostaluminum wires did.

THE WASHER TYPE specimens are con-cluded to be the most useful, giving virtually the same results as the more sensitive wire-on-bolt type.

ContactJohan Tidblad, [email protected]

Bimetallic corrosion under atmospheric conditions, effect of different types of specimens for field exposure tests

*) Corrosion of metals and alloys – Deter-mination of bimetallic corrosion in outdoor exposure corrosion tests, ISO/CD 7441, ISO/IEC TC 156/WG4, 2011-05-27

Congratulations to MUSECORR, which has been designated one of Horizon 2020’s success stories

Bimetallic corrosion under atmospheric conditions, effect of different types of specimens for field exposure tests

Lena Sjögren, Helen Pahverk and Johan Tidblad

Swerea KIMAB, Stockholm, Sweden.

In the suggested revision of the ISO-standard for the determination of bimetallic corrosion in atmospheric exposure corrosion tests*), three types of specimens for measuring bimetallic corrosion are described. In this work performance of these specimen types are compared. After one year atmospheric field exposure, corrosion of the anodic member of each

couple has been determined as mass loss and the bimetallic effect β calculated as ß = (rtest – rref)/(rtest + rref) where rtest is corrosion rate for the anodic member of the couple in contact with another metal and rref is the corrosion rate in contact with a plate/washer of the same metal or, for wire-on-bolt specimens, in contact with a nylon screw. Exposure sites, specimen types, and calculated bimetallic effects for selected material combinations are shown in the table below. Table - Bimetallic effect obtained for different specimen types after one year exposure at three sites: SV (Stockholm Vanadis low corrosivity urban atmosphere), BM (Bohus Malmön marine atmosphere) and Bo (Borås, road environment with de-icing salts).

Specimen type

Rectangular plates

Washers

Wire-on-bolt Exposure site

Anode/cathode SV BM Bo SV BM Bo SV BM Bo

AA1050/steel 0,6 0 a) 0,8 0,9 0,8 0,9 0,9 1b) 1b) HDG/steel 0,3 0,5 0,6 1c) 1c) 1c) 0,8 0,7 0,8 AA1050/copper 0,3 0,9 0,9 0,7 0,9 0,9 1,0 1b) 1b) 0a) no significant bimetallic effect 1b) wire broken for test specimen, not for reference 1c) significant bimetallic effect but very low mass loss for the reference

From the corrosion rates measured, the specimen types were found to differ in sensitivity, wire-on-bolt type specimens, with the whole anode area close to the cathode being the most sensitive and the rectangular type specimens showing the lowest sensitivity due to the relatively larger anode size. About the same bimetallic effect was found for the washer and wire-on-bolt type specimens while lower bimetallic effect was calculated for the rectangular plates as a result of the lower sensitivity. A disadvantage with wire-on-bolt type specimens is that all materials cannot be obtained as wires and that corroded wires may break, which most aluminum wires did. The washer type specimens are concluded to be the most useful, giving virtually the same results as the more sensitive wire-on-bolt type. *) Corrosion of metals and alloys – Determination of bimetallic corrosion in outdoor exposure corrosion tests, ISO/CD 7441, ISO/IEC TC 156/WG4, 2011-05-27

in short


Much-awaited revised edition of rustproofing handbook

TO MEET require-ments for function, safety and aesthet-ics, designers and manufacturers of steel components are dependent on corrosion protection. This type of protection is normally provided by rustproofing coating, a method that is widely used in many applications and has considerable economic ramifications.

We are pleased to be able to present the new, revised edition of Handbok i rostskyddsmål ning, the rustproofing handbook. Like its predecessors, from the first edition in 1935 to the previous one in 1999, it has been the result of teamwork.

Work towards this edition has been a collaborative effort of Swerea KIMAB and Auktorisation för Rostskyddsmålning.

An overview of the areaThe handbook is both a practical and a theoretical guide to the field of rustproof-ing coating. The intention has been to provide a general yet, in many respects, detailed overview of the area. It gives a good introduction to regulatory frame-works and fundamental standards, etc. Key aspects included in the revision are:• Introduction of new regulations for

steel and aluminium structures SS-EN 1090-2.

• Introduction guidance on the CLP Reg-ulation, which includes a new labelling system for hazard classification.

• New legislation and other regulations with respect to environment and work environment.

THE HANDBOOK is, in Swedish, sold and distributed by Swerea KIMAB. The price is SEK 700 plus sales tax and shipping.

ContactLouise Parnefjord, [email protected]

Understanding BiocorrosionFundamentals and Applications

THE BOOK IS INTENDED mainly for researchers and approaches the topic of biocorrosion from several differ-ent angles, such as analytical science, electrochemistry, materials and surface science, biochemistry and molecular microbial ecology. Claude Duret-Thual, of our French subsidiary Institut de la Corrosion, has written two of the chap-ters in the book. These are entitled “Un-derstanding corrosion: basic principles” and “The effect of H2S on the corrosion of steels”. The contents consist of sixteen chapters concerning topics of both a fundamental and practical nature.

To order the bookThe book, which is in English can be ordered via electronic booksellers as an e-book, or in a print version.

Contact Louise Parnefjord, [email protected]

General information Congress office

Brass Alloys 2016 Stockholm, Sweden

25–27 May 2016

Swerea KIMAB Brita BäckströmP.O. Box 7047SE-164 07 Kista, SwedenPhone +46 (0)8 440 48 00E-mail [email protected]

Local organising committeeTomas Hult, Swerea KIMABBrita Bäckström, Swerea KIMABMargaretha Sönnergaard, Swerea KIMABE-mail: [email protected]

Exhibition, sponsoring and accompanying programBrita BäckströmPhone +46 (0)8 440 48 00E-mail [email protected]

www.swerea.se

Registration feesThe registration fee is SEK 6 500* (Student SEK 3 500). Accompanying persons fee is SEK 2 300. Latest registration acceptance at those prices is April 1, 2016. After that date an extra fee of 20% will be charged. The fee includes congress participation, welcome reception, congress proceedings, lunches, refreshments and congress dinner. Accompa-nying persons have their own program. * 1USD=8,39 SEK, 2015-05-07.

RegistrationUse the online Registration form for attendee registration and for booking of hotel rooms – see our website www.swerea.se.

Cancellation and refundsCancellations before May 1, 2016 will be refun-ded. Thereafter 90% of the conference fee will be invoiced. Participation can be transferred to a colleague.

LanguageThe Congress language will be English.

LocationThe congress will take place on May 25–27, 2016 at Radisson Blu Royal Viking Hotel in Stockholm.

Radisson Blu Royal Viking Hotel Vasagatan 1, 101 24 Stockholm, SwedenTel: +46 8 50 65 40 00, Fax: +46 8 50 65 40 01www.radissonblu.com/royalvikinghotel-stockholm Call for papersFo

to: H

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Try

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TRIGGERED BY NEW rules and regulations, the international brass industry is currently facing major changes. Brasses are used in a wide range of applications such as plumb-ing fixtu-res, fittings and valves, bearings, radiators, decorative architectural and many more.

BRASS ALLOYS 2016 creating an internation-al arena for presentat-ions and information exchange, aiming to boost and facilitate on-going and future research work in the field of brass materials and processing.

MAIN TOPICS• Processdevelopmentandoptimisation• Alloyandproductdevelopment• Corrosionpropertiesandtesting• Formingandmachining• Recyclingandrefining

IMPORTANT DATESAbstract deadline ..............October 1, 2015Abstract acceptance notifications ..........................November 15, 2015Manuscripts due ................January 29, 2016 Registration deadline .....April 22, 2016

More info:www.swereakimab.se


Calendar May 20–22, 201516th Nordic Corrosion CongressLocation: Stavanger, Norway

More information at www.ncc2015.no

June 2–6, 2015 CEOCOR 2015 Location: Stockholm, Sweden

November 17–18, 2015 LIGHTer International Conference 2015 Location: Gothenburg Sweden

More information at www.swereakimab.se

November 18. 2015 Swerea KIMAB Member Day 2015Location: Swerea KIMAB, Stockholm, Sweden


More information at www.institut-corrosion.fr

Certification in cathodic protection for the seawater application sector:

Level 1 June 15–22 (English)Examination: June 23 & 24October 12–16 & 26 (French) Examination: October 27 & 28

Level 2 October 12–23October 19–23Examination: October 27 & 28In French (English on demand)

Courses


FRANCE SWEDEN

Skadeutredning &grundorsaksanalysOctober 13–15, 2015in Swedish.

Korrosionslära Part 1: November 10–12Part 2: November 25–26 In Swedish

Documents

Collaboration - Swerea · systems. CEOCOR brings together specialists from universities, research centres, ... Support to SME’s within the surface finishing industry 21 ... this