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© inspire AG, irpd

Manfred Schmid, inspire AG, irpd, CH-9014 St. Gallen

Berlin, 4. März 2015

STRATEGIEN FÜR DIE DRITTE INDUSTRIELLE REVOLUTION

© inspire AG, irpd

� Introduction

Institute inspire-irpd, SLS principle, plastics pyramid

� SLS-Powders – ‘state of the art’

basic properties, different powders, market & current

assortment, limitations

� SLS-Powders – ‘research & recent developments’

combination of properties, ‘exotic’ polymers and commodities

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© inspire AG, irpd

University of

Applied Science

Industry

SME‘s

basic application technology product

R&D driven R&D development development

Competence centre for the Swiss Industry regarding production technique and tooling.

Founded on an initiative of ETH-Zürich and machine building industry. Approved as ETH-research annex institute (non-profit foundation).

knowledge and technology transfer process

© inspire AG, irpd

Selective Laser Sintering (SLS) - principle

powder

supply

Part

cylinder

sintered

part

Convection

IR heater LASER

Beam

roller / blade for powder distribution

powder

supply

IR heater IR heater� layer thickness: 100 µm

� temperature: 170°C

� CO2-laser: λ = 10.6 µm

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© inspire AG, irpd

Selective Laser Sintering (SLS): process steps to control

© inspire AG, irpd

market

share:

~1%

~5%

~94%

HP –Plastics

Use (°C): 160-260price: > 15 $/kg

Engineering Plastics

Use (°C): < 140price: 5 to 10 $/kg

Standard Plastics

Use (°C): < 90price: < 2 $/kg

amorphous partially crystalline

price

& p

erf

orm

ance

Plastics pyramid: properties, quantity, price

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© inspire AG, irpd

PA, PET, POM

market

share:

~1%

~5%

~94%

PE, PP, PS, PMMA

HP –Plastics

Use (°C): 160-260price: > 15 $/kg

Engineering Plastics

Use (°C): < 140price: 5 to 10 $/kg

Standard Plastics

Use (°C): < 90price: < 2 $/kg

amorphous partially crystalline

price

& p

erf

orm

ance

Plastics pyramid: properties, quantity, price

© inspire AG, irpd

Plastics pyramid: reality for SLS

HP –Plastics : PEK

Engineering

Plastics

Standard

Plastics

: PA12, PA 11

: PP, TPE, PS

price: > 500 $/kg

price: 60 - 100$/kg

price: 60 - 200 $/kg

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Commercial Materials:

PA12 unfilled: 3D-Systems, EOS, Arkema, ALM, Exceltec

differs in particle distribution and recyclability

PA12 filled: 3D-Systems, EOS, ALM, Exceltec, Windform

mainly: aluminum, glass beads, carbon & mineral

PA11 unfilled: 3D-Systems, EOS, Arkema, ALM, Windform

difficult to process but excellent EaB

‘Exotic polymers’: PEEK, PP, PS, TPU, PEPA(X)

Market share:

90-95%

© inspire AG, irpd

Arkema (F)Orgasol® Invent Smooth

3D Systems (USA)Duraform® PA

EOS (D)PA2200/2001

Market situation: the commercial PA 12 materials

Evonik (Vestosint®) Arkema (Orgasol®)

PA 2200

µm

DuraForm® PA

µm

Orgasol® Invent Smooth

µm

100 µm 100 µm 100 µm

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© inspire AG, irpd

Market situation: the commercial PA 12 and PA 11 materials

WindFormDirect sales

ExcelTec (F)Direct sales

ALM (EOS)Direct sales

Arkema (F)Direct sales PA12/11

Evonik Arkema[A]

[B]

[C]

Orgasol® IS

3D Systems (USA)Direct sales

EOS (D)Direct sales

PA 12: Duraform® PA, PA 2200

PA 12 GB filled

PA 12 Al filled

Rilsan® Invent

PA 12 CF filled PA 11 GB filled

[A] neat material[B] confectioner[C] available mixtures

PA 12 MF filled„dry blends“!

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74 J/m ☺32 J/mImpact strength (Izod)

47% ☺14%Elongation at break

37 MPa43 MPaTensile strength

ca. 1'500 MPaca. 1'500 MPaE-modul (MPa)

limited�goodRecyclability

small (<10°C) �large (>20°C)SLS Process window

188 - 195°C178 - 187°CMelting point

α-triklinγ- monoklinCrystal structure

PA11PA12PA12 / PA11 for SLS in

comparison

SLS - Standardpolymere

� suitable sintering temperatures (large window)

� low melt viscosity (for medium mol weight (Mw))

� Intrinsically good mechanical properties (H-bonds)

SLS-Powders – ‘state of the art’

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© inspire AG, irpd

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

10000

0 10 20 30 40 50 60 70

Young's M

odulus XY [MPa]

Elonga on at break XY [%]

PA12

PA12 Glass Beads

PA12 Carbon fibers

PA12 Aluminum

PA 11

PA 11 filled

PA

12 -

CF

PA11PA12

PA12 GB/MF

PA12 Al

Properties of the commercial PA 12 and PA 11 materials

© inspire AG, irpd

0

10

20

30

40

50

60

70

80

Ten

sil

e s

tren

gth

[M

Pa]

XY-direction Z-direction

PA12 types PA11 types reinforced types

still 10-30%

loss of

mechanical

properties in

Z-direction

Anisotropy of properties

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© inspire AG, irpd

5 main topics:

> Thermal behavior

- sintering window

> Particle

- spherical- smooth surface

> Powder

- distrib. (20-80 µm)

> Rheology

- low zero viscosity

> Optical properties

- absorption 10.6 µm

combination of properties

© inspire AG, irpd

thermal situation in building chamber

SLS-Material: thermal situation during build

thermodynamic: super-cooled liquid; meta-stable phase (solid/liquid at the same time)

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© inspire AG, irpd

Sources: LSS, GmbH/B. Caulfield et al. (2007)

6 controlled zones

2 controlled zones ∆tmax

=10ºC

∆tmax =4ºC 97% area

Temperature distribution build platform surface

© inspire AG, irpd

Ts

Lateral growth and

curling trade

off with part

bed

temperature

Lateral growth

Curling

∆T Part bed:

5°C !

164°

C

168°

C

� Thermal control of SLS processing is a key factor for success

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© inspire AG, irpd

O O C

O

n

Material very expensive and not recyclable!

source EOS

© inspire AG, irpd

First TPU for SLS

from Lehmann & Voss

- tricky to process;

- great detail resolution;

- high flexible material;

SLS-Materials: Polyurethan

outstanding

Elongation at break

EaB > 350%

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© inspire AG, irpd

SLS-Materials: Polyamide 6

Material for increased thermal

and mechanical treatment;

Powder must be in a controlled

drying condition;

Large properties difference

between parts in dry/conditioned

status

Norm Einheit Werte d.a.m. Cond.

Allgemeine Materialkennwerte:

Dichte der lasergesinterten Bauteile ISO 1183 g/cm3 1,13

Wasserabsorption bei Sättigung (23°C RH50)/Artikel ISO 62 % 3,3

Wasserabsorption bei Sättigung (23°C

RH50)/Pulver

ISO 62 % 4,1

Schüttdichte ISO 60 g/cm3 0,6

Partikelgröße (D10) ISO 13320-1 µm 32

Partikelgröße (D50) ISO 13320-1 µm 66

Partikelgröße (D90) ISO 13320-1 µm 122

Mechanische Kennwerte:

Zugmodul (23°C) ISO 527 Type 1A MPa 3360 1270

Reißfestigkeit(23°C) ISO 527 Type 1A MPa 77 40

Bruchdehnung (23°C) ISO 527 Type 1A % 3,4 20

Biegemodul ISO 178 MPa 2500 980

Charpy Kerbschlagzähigkeit (23°C) ISO 179/1fU kJ/m² 2 4,7

Thermische Kennwerte:

Erster Schmelzpunkt (2°C/min) ISO 11357-3 °C 210

Wärmeformbeständigkeit (0,45 MPa) ISO 75/Af °C 191

Wärmeformbeständigkeit (1,8 MPa) ISO 75/Bf °C 77

© inspire AG, irpd

SLS-Materials: iCoPP

authorized by:iCoPP polypropylene (PP) for Selective Laser Sintering!

� outstanding impact and chemical resistance� sterilisable (medical)� sealability with other PP-parts

� Special powders designed for cosmetic industry: > 150 €/kg!