Basic Corr Chapter 1

Welcometo the

Basic Corrosion course

Basic Corrosion Course

The goal of this course is to provide

interested persons with a basic

overview of the theoretical and

practical aspects of corrosion and

its control.

What do we expect you to have to be successful in this course?

An interest in learning more about corrosion

Chapter 1–Introduction

Basic Corrosion Course

Corrosion Definition

The deterioration of a substance

(usually a metal) or its properties

because of a reaction with its

environment.

Are all of these Corrosion?

Corrosion Affects You!

Your Environment

Your Company

Your Job

Your Safety

Your Pocketbook

Total Direct Cost of Corrosion in the U.S.

B$276 / year = 3.1% of GDP

Source: Corrosion Cost and Preventative Strategies in the United States, September 2001, Report FHWA-RD-01-156

Cost of Corrosion

$8.3$7.0

$0.3$7.0

$-$-

$5.0$36.0

$6.9$-

$23.4$2.7

$2.2$0.5$0.9$1.4

$0.1$3.7

$1.7$6.0

$1.1$2.1

$-$1.5

$20.0$0.1

$- $10 $20 $30 $40

1.00

Cost Of Corrosion Per Analyzed Economic Sector, ($ x billion)

Highway BridgesGas and Liquid Transm. PipelinesWaterways and PortsHazardous Materials StorageAirportsRailroadsGas DistributionDrinking Water and Sewer SystemsElectrical UtilitiesTelecommunicationMotor VehiclesShipsAircraftRailroad CarsHazardous Materials TransportOil and Gas Expl.and ProductionMiningPetroleum RefiningChem., Petrochem., Pharm.Pulp and PaperAgriculturalFood ProcessingElectronicsHome AppliancesDefenseNuclear Waste Storage

Cost of Corrosion per Analyzed Economic Sector, ($x billion)

Direct Corrosion Costs

Excessive Maintenance /Repair/ReplacementLost Production/DowntimeProduct ContaminationLoss of Product

Loss of Efficiency (Oversizing & Excess)Energy CostsAccidentsIncreased Capital Costs – OverdesignEnvironmental Cleanup – Fines

Indirect Corrosion Costs

SafetyStructural CollapseLeaksFire/Toxic ReleasesProduct ContaminationFoods/Pharmaceuticals WaterConsumer ConfidenceLoss of RedundancyAppearance Increased Regulation

Forms of Corrosion

General CorrosionLocalized Corrosion Pitting Crevice Corrosion Filiform CorrosionGalvanic CorrosionEnvironmental Corrosion CrackingFlow-Assisted CorrosionIntergranular CorrosionDealloyingFretting CorrosionHigh Temperature Corrosion

General Corrosion

Stress Corrosion Cracking

Pitting Corrosion

Is this General, or Localized?

Crevice Corrosion

Is it General or Localized?

Filiform Corrosion

Is it General or Localized?

Galvanic Corrosion

Is this General, or Localized?Is it General or

Localized?

Velocity Effect Corrosion-

Erosion Corrosion

Is it General or Localized?

Intergranular Corrosion

De-Alloying

Fretting

High-Temperature Corrosion

What causes the corrosionof metals?

There is an imbalance of energy thatequalizes during corrosion processes (non-equilibrium)

The “balancing” process is called anelectrochemical reaction which we willstudy in the next chapter.

We must study the atoms to understandthis process.

Where can I obtain more informationabout corrosion?

NACE InternationalAmerican Gas Association American National Standards InstituteAmerican Petroleum InstituteAmerican Society of Mechanical EngineersAmerican Society for Testing and Materials ASM InternationalMaterials Technology InstituteSSPC-The Society for Protective CoatingsSteel Tank Institute UK Institute of Corrosion

Types of Information

These organizations produce:

Standards Papers Publications & Software Training Courses and Conference Events Knowledge Bases on the Internet