1

Zilveren jubileum

1990-2015

25 years of pioneering work in

Additive Manufacturing

at KU Leuven

Prof. Dr. Ir. Jean-Pierre Kruth

KU Leuven, Belgium

Fellow CIRP, FSME

Bower Awardee / Franklin Institute Laureate

• A whole bunch of techniques to produce “objects” by gradually adding material until the desired 3D geometry is obtained. Material is often added layer upon layer.

What is Additive Manufacturing (AM) or 3D Printing?

2

• A whole bunch of techniques to produce “objects” by gradually adding material until the desired 3D geometry is obtained. Material is often added layer upon layer.

• The 1st technologies appeared around 1990.

What is Additive Manufacturing (AM) or 3D Printing?

• A whole bunch of techniques to produce “objects” by gradually adding material until the desired 3D geometry is obtained. Material is often added layer upon layer.

• The 1st technologies appeared around 1990.

• “Additive Manufacturing” is complementing traditional “Subtractive Manufacturing” (drilling, milling, grinding, …) known for centuries and “Forming technologies” (casting, forging, extrusion, deep drawing, injection molding, …) going back to the prehistory.

What is Additive Manufacturing (AM) or 3D Printing?

Milling machine Casting metal

Forging

3

• A whole bunch of techniques to produce “objects” by gradually adding material until the desired 3D geometry is obtained. Material is often added layer upon layer.

• The 1st technologies appeared around 1990.

• “Additive Manufacturing” is complementing traditional “Subtractive Manufacturing” (drilling, milling, grinding, …) known for centuries and “Forming technologies” (casting, forging, extrusion, deep drawing, injection molding, …) going back to the prehistory.

• “3D Printing” is a vulgarizing synonymous for “Additive Manufacturing” (ISO/ASTM standards)

What is Additive Manufacturing (AM) or 3D Printing?

• A whole bunch of techniques to produce “objects” by gradually adding material until the desired 3D geometry is obtained. Material is often added layer upon layer.

• The 1st technologies appeared around 1990.

• “Additive Manufacturing” is complementing traditional “Subtractive Manufacturing” (drilling, milling, grinding, …) known for centuries and “Forming technologies” (casting, forging, extrusion, deep drawing, injection molding, …) going back to the prehistory.

• “3D Printing” is a vulgarizing synonymous for “Additive Manufacturing” (ISO/ASTM standards)

• AM applies very different processes (SLA, SLS/SLM, FDM, LOM, …), often only suited for a very limited set of materials (photo-polymers, technical polymers, metals/alloys, ceramics, composites,…), and for very diverse applications:

– Prototyping: initial application (Rapid Prototyping)

– Tooling: e.g. plastic injection molding (inserts)

– Industrial mfg.: mechanical, automotive, aerospace, electronics, consumer devices, etc.

– Medical: medical models, prostheses, implants, scaffolds, tissue, (organs), etc.

– Dental: see medical, but quite different market

– Architecture and construction: mock-ups, printing structures (and houses)

– Artwork, fashion, design

– Consumer/Prosumer: home application, DIY (Do-It-Yourself), amateurs

– Production of food and medication

A lot of combinations; many specializations. KU Leuven: powder-based and laser-based AM.

What is Additive Manufacturing (AM) or 3D Printing?

4

Industrial application of AM appeared only around 1990 because it is an automated process, requiring computers and CAD/CAM systems (digital computer model, 1980’s)

How old is Additive Manufacturing (AM)?

From subtractive manufacturing (SM) to additive manufacturing (AM)

Cappadocia

Typical CIM scenario for Additive Manufacturing (AM)

• CIM = Computer Integrated Manufacturing

• Based on: – CAD = Computer Aided Design (in casu “3D Solid Modeller”)

– CAM = Computer Aided Manufacturing

Triangulated/Facetted Model (STL file)

Sliced Model (Contour file)

Part build in slices with support structure

CAD Model

5

Examples of Additive Manufacturing processes

Start phase Process Lay-out Layer deposition Phase change Materials

LIQ

UID

Stereo lithography Liquid resin in a vat,

irradiated by UV light (laser) Liquid layer deposition Photo-polymerization

Acrylates, epoxies, filled

resins

Ink jet Printing Droplets of melted material Deposition of droplets

through nozzle Solidification by cooling Polymers, wax

Fused Deposition

Modeling Material melted in a nozzle

Continuous extrusion and

deposition Solidification by cooling (Filled) Polymers, wax

PO

WD

ER

Three-dimensional

printing

Binder projected on powder

in bed

Layer of powder and drop

on demand binder

deposition

No phase change of

powder, solidification by

injection of binder

Ceramics/ metals/

polymers with polymer

binder

Selective Laser

Sintering/Melting

Powder bed, radiation by

laser Layer of powder

Laser sintering and

melting, re-solidifying

while cooling

Polymers, metals (ferro,

non-ferro), ceramics, all

composites (e.g.

cermets, Al-PA, Cu-PA)

Electron Beam

Melting

Powder bed pre-heated

and radiated by electron

beam

Layer of powder

Electron beam

melting, re-solidifying

while cooling

Non-magnetic, non-

ferro metals (Ti, CoCr)

Laser Cladding Powder injected thru

nozzle(s) in laser spot

Continue powder

injection

Laser melting and re-

solidifying by cooling

Metals, metal

composites

SO

LID

Laminated Object

Manufacturing

Feeding, cutting and binding

of sheets

Deposition of sheet

material

Binding by phase change

of solder, glue or

otherwise

Paper, Polymer foam,

composites, metals,

ceramics

GA

S Selective Laser

Chemical Vapour

Deposition

Gas flow in laser Condensation of gas Solidification by chemical

reaction Metals, ceramics

Examples of Additive Manufacturing processes

Photo-polymerisation of liquid polymer (Stereo-lithography) Process only suited for: - Dedicated photo-polymers

(no technical polymers, no metals, etc.)

- Basically prototyping

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Examples of Additive Manufacturing processes

Extrusion based AM (FDM – Fused Deposition Modelling)

Ultimaker Original

Process only suited for: - Polymers

(technical polymers, like ABS, etc.)

Examples of Additive Manufacturing processes

Powder Bed Fusion (Selective Laser Sintering/Melting – SLS/SLM)

Process suited for: - Polymers - Metals - Ceramics - Composites (metal-metal, metal-ceramic, plastic-

metal, plastic-glass, fibre-reinforced, etc.)

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• Starts from CAD model of the object

• Allow to produce very complex 3D shapes: – 3D complexity decomposed in simple 2D contours

Main features of Additive Manufacturing

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• Starts from CAD model of the object

• Allow to produce very complex 3D shapes: – 3D complexity decomposed in simple 2D contours

– Free-form doubly-curved shapes

– Parts with internal cavities

– Parts requiring assembly of e.g. 20 parts now produced as 1 part

Main features of Additive Manufacturing

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• Starts from CAD model of the object

• Allow to produce very complex 3D shapes: – 3D complexity decomposed in simple 2D contours

– Free-form doubly-curved shapes

– Parts with internal cavities

– Parts requiring assembly of e.g. 20 parts now produced as 1 part

Main features of Additive Manufacturing

15

Courtesy: ESA

• Starts from CAD model of the object

• Allow to produce very complex 3D shapes: – 3D complexity decomposed in simple 2D contours: picture

– Free-form doubly-curved shapes

– Parts with internal cavities

– Parts requiring assembly of e.g. 20 parts now produced as 1 part

• Simple/short job preparation: single operation, machine, tool, set-up (no fixtures)

• Simple production: single set-up, no need for many (dedicated) tools

• Fast throughput (mfg. process still slow)

• Ecological mfg.: creates material only where needed, no spooling of material

• Local manufacturing in small mfg. units or quantities: – Counters delocalisation

– Reduce CO2 footprint: no transport of goods (produced e.g. in Japan) across the world

– Production in (war)ship, spacecraft, other planet, at home, etc.

• Single part, customized products: e.g. single plastic part, medical implants.

• New/customized materials: the material is created during part manufacturing

Main features of Additive Manufacturing

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9

• AM applies very different processes (SLA, SLS/SLM, FDM, LOM, …), often only suited for a very limited set of materials (photo-polymers, technical polymers, metals/alloys, ceramics, composites,…), and for very diverse applications:

– Prototyping: initial application (Rapid Prototyping)

– Tooling: e.g. plasting injection molding (inserts)

– Industrial mfg.: mechanical, automotive, aerospace, electronics, consumer devices, etc.

– Medical: medical models, prostheses, implants, scaffolds, tissue, (organs), etc.

– Dental: see medical, but quite different market

– Architecture and construction: printing structures (and houses)

– Artwork, fashion, design

– Consumer/Prosumer: home application, DIY (Do-It-Yourself), amateurs

– Production of food and medication

A lot of combinations; many specializations. KU Leuven: powder-based and laser-based AM.

Applications of Additive Manufacturing (AM) or 3D Printing

• AM applies very different processes (SLA, SLS/SLM, FDM, LOM, …), often only suited for a very limited set of materials (photo-polymers, technical polymers, metals/alloys, ceramics, composites,…), and for very diverse applications:

– Prototyping: initial application (Rapid Prototyping)

– Tooling: e.g. plasting injection molding (inserts)

– Industrial mfg.: mechanical, automotive, aerospace, electronics, consumer devices, etc.

– Medical: medical models, prostheses, implants, scaffolds, tissue, (organs), etc.

– Dental: see medical, but quite different market

– Architecture and construction: printing structures (and houses)

– Artwork, fashion, design

– Consumer/Prosumer: home application, DIY (Do-It-Yourself), amateurs

– Production of food and medication

Applications of Additive Manufacturing (AM) or 3D Printing

10

• AM applies very different processes (SLA, SLS/SLM, FDM, LOM, …), often only suited for a very limited set of materials (photo-polymers, technical polymers, metals/alloys, ceramics, composites,…), and for very diverse applications:

– Prototyping: initial application (Rapid Prototyping)

– Tooling: e.g. plasting injection molding (inserts)

– Industrial mfg.: mechanical, automotive, aerospace, electronics, consumer devices, etc.

– Medical: medical models, prostheses, implants, scaffolds, tissue, (organs), etc.

– Dental: see medical, but quite different market

– Architecture and construction: printing structures (and houses)

– Artwork, fashion, design

– Consumer/Prosumer: home application, DIY (Do-It-Yourself), amateurs

– Production of food and medication

Applications of Additive Manufacturing (AM) or 3D Printing

10 mm

• AM applies very different processes (SLA, SLS/SLM, FDM, LOM, …), often only suited for a very limited set of materials (photo-polymers, technical polymers, metals/alloys, ceramics, composites,…), and for very diverse applications:

– Prototyping: initial application (Rapid Prototyping)

– Tooling: e.g. plasting injection molding (inserts)

– Industrial mfg.: mechanical, automotive, aerospace, electronics, consumer devices, etc.

– Medical: medical models, prostheses, implants, scaffolds, tissue, (organs), etc.

– Dental: see medical, but quite different market

– Architecture and construction: printing structures and houses

– Artwork, fashion, design

– Consumer/Prosumer: home application, DIY (Do-It-Yourself), amateurs

– Production of food and medication

Applications of Additive Manufacturing (AM) or 3D Printing

11

• AM applies very different processes (SLA, SLS/SLM, FDM, LOM, …), often only suited for a very limited set of materials (photo-polymers, technical polymers, metals/alloys, ceramics, composites,…), and for very diverse applications:

– Prototyping: initial application (Rapid Prototyping)

– Tooling: e.g. plasting injection molding (inserts)

– Industrial mfg.: mechanical, automotive, aerospace, electronics, consumer devices, etc.

– Medical: medical models, prostheses, implants, scaffolds, tissue, (organs), etc.

– Dental: see medical, but quite different market

– Architecture and construction: printing structures and houses

– Artwork, fashion, design

– Consumer/prosumer: home application, DIY (Do-It-Yourself), amateurs

– Production of food and medication

Applications of Additive Manufacturing (AM) or 3D Printing

• AM applies very different processes (SLA, SLS/SLM, FDM, LOM, …), often only suited for a very limited set of materials (photo-polymers, technical polymers, metals/alloys, ceramics, composites,…), and for very diverse applications:

– Prototyping: initial application (Rapid Prototyping)

– Tooling: e.g. plasting injection molding (inserts)

– Industrial mfg.: mechanical, automotive, aerospace, electronics, consumer devices, etc.

– Medical: medical models, prostheses, implants, scaffolds, tissue, (organs), etc.

– Dental: see medical, but quite different market

– Architecture and construction: printing structures and houses

– Artwork, fashion, design

– Consumer/Prosumer: home application, DIY (Do-It-Yourself), amateurs

– Production of food and medication

Applications of Additive Manufacturing (AM) or 3D Printing

12

• AM applies very different processes (SLA, SLS/SLM, FDM, LOM, …), often only suited for a very limited set of materials (photo-polymers, technical polymers, metals/alloys, ceramics, composites,…), and for very diverse applications:

– Prototyping: initial application (Rapid Prototyping)

– Tooling: e.g. plasting injection molding (inserts)

– Industrial mfg.: mechanical, automotive, aerospace, electronics, consumer devices, etc.

– Medical: medical models, prostheses, implants, scaffolds, tissue, (organs), etc.

– Dental: see medical, but quite different market

– Architecture and construction: mock-ups, printing structures (and houses)

– Artwork, fashion, design

– Consumer/Prosumer: home application, DIY (Do-It-Yourself), amateurs

– Production of food and medication

Applications of Additive Manufacturing (AM) or 3D Printing

• AM applies very different processes (SLA, SLS/SLM, FDM, LOM, …), often only suited for a very limited set of materials (photo-polymers, technical polymers, metals/alloys, ceramics, composites,…), and for very diverse applications:

– Prototyping: initial application (Rapid Prototyping)

– Tooling: e.g. plasting injection molding (inserts)

– Industrial mfg.: mechanical, automotive, aerospace, electronics, consumer devices, etc.

– Medical: medical models, prostheses, implants, scaffolds, tissue, (organs), etc.

– Dental: see medical, but quite different market

– Architecture and construction: mock-ups, printing structures (and houses)

– Artwork, fashion, design

– Consumer/Prosumer: home application, DIY (Do-It-Yourself), amateurs

– Production of food and medication

Applications of Additive Manufacturing (AM) or 3D Printing

13

• AM applies very different processes (SLA, SLS/SLM, FDM, LOM, …), often only suited for a very limited set of materials (photo-polymers, technical polymers, metals/alloys, ceramics, composites,…), and for very diverse applications:

– Prototyping: initial application (Rapid Prototyping)

– Tooling: e.g. plasting injection molding (inserts)

– Industrial mfg.: mechanical, automotive, aerospace, electronics, consumer devices, etc.

– Medical: medical models, prostheses, implants, scaffolds, tissue, (organs), etc.

– Dental: see medical, but quite different market

– Architecture and construction: printing structures (and houses)

– Artwork, fashion, design

– Consumer/Prosumer: home application, DIY (Do-It-Yourself), amateurs

– Production of food and medication

Applications of Additive Manufacturing (AM) or 3D Printing

• AM applies very different processes (SLA, SLS/SLM, FDM, LOM, …), often only suited for a very limited set of materials (photo-polymers, technical polymers, metals/alloys, ceramics, composites,…), and for very diverse applications:

– Prototyping: initial application (Rapid Prototyping)

– Tooling: e.g. plasting injection molding (inserts)

– Industrial mfg.: mechanical, automotive, aerospace, electronics, consumer devices, etc.

– Medical: medical models, prostheses, implants, scaffolds, tissue, (organs), etc.

– Dental: see medical, but quite different market

– Architecture and construction: printing structures (and houses)

– Artwork, fashion, design

– Consumer/Prosumer: home application, DIY (Do-It-Yourself), amateurs

– Production of food and medication

Applications of Additive Manufacturing (AM) or 3D Printing

14

• AM applies very different processes (SLA, SLS/SLM, FDM, LOM, …), often only suited for a very limited set of materials (photo-polymers, technical polymers, metals/alloys, ceramics, composites,…), and for very diverse applications:

– Prototyping: initial application (Rapid Prototyping)

– Tooling: e.g. plasting injection molding (inserts)

– Industrial mfg.: mechanical, automotive, aerospace, electronics, consumer devices, etc.

– Medical: medical models, prostheses, implants, scaffolds, tissue, (organs), etc.

– Dental: see medical, but quite different market

– Architecture and construction: printing structures (and houses)

– Artwork, fashion, design

– Consumer/Prosumer: home application, DIY (Do-It-Yourself), amateurs

– Production of food and medication

Applications of Additive Manufacturing (AM) or 3D Printing

• 1970-1980’s: strong expertise in conventional (milling, grinding,…) and non-conventional (EDM,…) subtractive manufacturing, plastic injection molding (moldmaking), CAD/CAM, etc.

• 1990: Start of activities on Rapid Prototyping, dixit AM (polymers):

– Incorporation of Materialise N.V. (Additive Manufacturing of polymers) within KU Leuven labs

– 1st Stereo-Litography Apparatus SLA-250 (3D Systems)

– Own-built SLA machine: Materialiser I, Mammoth SLA, Curtain recoater SLA (patent), Colour SLA (patent)

– Ink jet printing of polymers

• 1991: Start of activities on AM for metals:

– 1st tests with electron beam sintering/melting (EBM)

– 1st tests with selective laser sintering/melting (SLS/SLM)

– Building own SLS/SLM machines (Nd:YAG laser, fiber laser, process monitoring, …)

• 1997: Purchase of DTM Sinterstation 2000+ (100W CO2 laser)

– SLS of polymers, metals (Rapidsteel, Laserform), hardmetals (WC-Co, etc.), titanium,…

• 2008: Incorporation of LayerWise N.V. (AM of metals)

• 2008: Initiating new research on SLS/SLM of ceramics, X-ray CT quality control, …

History of Additive Manufacturing at University Leuven

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Laser Additive Manufacturing

1st SLA-250 machine installed in 1990

Colour stereolithography (patent)

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dip wait rise sweep(x n)

lower + wait

Dip and blade scraper re-coater (3D System)

Liquid curtain re-coater (K.U.Leuven)

lower sweep

Casting re-coater (EOS)

lower sweep return

inject

Resin sucked byT-shaped bar(Teijin Seiki)

Resin sucked byinterfacial force(CMET)

Variants

Curtain casting head

liquid curtain

v

re-coater head

narrow gap

deposited layer

Q

Scanning behind scraper (Japan)

Variants

LaserbeamBlade

LaserbeamBlade

Opticalflat

Suction re-coater (3D System’s Zephyr/SmartSweep re-coater)

lower sweep

suck

part

liquid resin

Manufacturer : Materialise, Belgium

Process : Mammoth Stereolithography machine (max. dim. 2200x840x640mm)

Product : Ford Mondeo dashboard (2700 layers, 52h build time)

on Rapid-Fit modular fixture

Features Mammoth SLA machine

•Liquid curtain recoating (patent)

•4 parallel scanners, 1 laser

Large stereolithography part - Mammoth SL machine

RapidFit fixture for

Quality Control

Selective Laser Sintering of polymers (SLS)

Digital design from wax imprint SLS production (500 parts) Pigmented shells before & after finishing

Customised hearing aids (Courtesy Materialise – Siemens-Phonak)

Bone scaffolds in PA & PCL

Tibia bone

Components in PA & elastomer

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Selective Laser Sintering of polymers (SLS)

Development of new Polymers for SLS

500% elongation Strong elasticity

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5 m

m

Very flexible novel material

Development AM novel polymers or reliability existing polymers => Cooperation between KU Leuven (Mech. Eng./PMA and CIT), Materialise and others

Laser Additive Manufacturing

1st SLS/SLM/EBM tests in 1991 (own setups)

to

From

Cooperation KU Leuven PMA + MTM

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• Company: LayerWise N.V., Leuven

• Field: RP & AM of metalic products

• Spin-off of KU Leuven

• Start: 2008 (Founders: CEO P. Mercelis, CEO J. Van Vaerenbergh,

KU Leuven J.P. Kruth)

• Today: 85 persons

• Activities:

– Industrial, medical & dental applications

– Several patents (dental and others)

• 2014: became part of 3D Systems

Additive Manufacturing by SLM of metal powder

10 mm

World’s first full lower jaw produced by SLM in Ti and implanted in patient of 81 years old

(LayerWise, 2012)

LayerWise – Rapid Prototyping & Manufacturing for metals

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Research in SLM of metals

– Expanding material pallet : tuning material, new compositions and alloys

– Improving part and material properties • Density

• Surface quality

• Microstructure

• Strength, Toughness, Fatigue

• Residual stresses: warpage and cracking of parts

• Post-treatment, heat treatment

• Biocompatibility

– Machine and process development (Hardware/Software)

• Building own machines: new lasers, scanners, temperature control, software (scanning, etc.)

• Optimization of processing parameters & window

• Real-time process monitoring and control

• Accuracy

• Speed

– In-line and off-line Quality Control

– Combined additive & subtractive laser manufacturing

– Precision & Micro-manufacturing

– Etc.

Cooperation KU Leuven PMA + MTM

Laser Additive Manufacturing

After polymers and metals, now also ceramics

Emblem statue of Brussels city

Cooperation KU Leuven PMA + MTM

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Need for quality control

• On-line or In-process QC (real-time) Monitoring & control of melt pool using high-speed thermal camera

• Off-line or final QC (accuracy, properties) Use of X-ray CT technology to check dimensional accuracy (outer and inner geometry) and material quality in one measuring inspection job

Quality monitoring & control in Additive Manufacturing

Cooperation KU Leuven PMA + Campus Groep T

Thank you for your attention.

Laser Additive Manufacturing: polymers, metals & beyond