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DPP - Optimization potentials by Laser based manufacturing

Simon Merkt Altair Conference 2013

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Agenda

Introduction und Motivation

Topology Optimization and Selective Laser Melting (SLM)

New needs

Conclusion and Outlook

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Digital Photonic Production – “From Bits to Photons to Atoms”

Unique properties of light …

highest energy density

highest speed

shortest interaction (precision)

mass-less, force-less

best controllability (CAD to product)

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Digital Photonic Production – Basic Principles

Cutting

Ablation AM Polishing Analytics

Welding Drilling Glass drilling

Laser

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Additive Manufacturing – Selective Laser Melting

metal powder lowering the platform

melting of the powder

application of powder layer

metal part made of serial material

3D-CAD model subdivided into layers

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Selective Laser Melting – Examples

Blankholder side panel

Pulley

Chassis component

Kinematics component

Blankholder

Blankholder

Holder gas-filled absorber

Closure clamp

Chassis component Damper intake

Luggage rack holder

Kinematics component seat adjustment

HKL hinge

Brake line holder

Hose holder

Heat protection blank steering gear

Source: N. Skrynecki, Kundenorientierte Optimierung des generativen Strahlschmelzprozesses, 2010

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Technology potential of SLM

Product complexity

Conventional manufacturing

Lot size

Digital Photonic Production

Conventional manufacturing

Innovative business models

Individualisation for free Individualisation for free Complexity for free

Innovative products

Piece Cost Piece cost

Digital Photonic Production

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Agenda

Introduction und Motivation

Topology Optimization and Selective Laser Melting (SLM)

New needs

Conclusion and Outlook

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Topology optimization of an upright (1)

Conventional design

Topology optimization

dummy FEM model

Topology optimization

result Final design

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Stub axle for Formula Student Team Running Snails (220 x 160 mm)

Material: AlMgSc (Scalmalloy® EADS trademark)

Dimension: app. 220 mm x 160 mm Weight: app. 400g

2,5 cm

Laser power: PL = 200 W PL= 500 W

Focus diameter: ds = 200 µm ds= 200 µm

Scanning velocity: vscan = 500 mm/s vscan = 1250 mm/s

Theoretical build-up rate: V = 5 mm³/s V = 12,5 mm³/s

x 2,5

Topology optimization of an upright (2)

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SLM-manufactured upright

First AlMgSc (Scalmalloy®) part manufactured by HP-SLM Weight saving: approx. 20 %

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Upright comparison

Evaluation criteria 2011 2012

Manufacturing process High Speed Cutting Selective Laser Melting

Optimization technique Iterative design with FEM-analysis

Topology optimization withSIMP

Material AlMgCuZn15/F52 AlMgScZr

Tensile strengh (Rm) ~520 MPa ~500 MPa

Final weight 0.502 kg (100%) 0.420 kg (83,7%)

Performance Max. displacement:0.19 mmMax. Stress:184 MPa

Max. displacement:0.14 mmMax. Stress:124 MPa

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Bionic upright for RWTH Formula Student Team

Material: AlSi10Mg Weight saving: approx. 30 %

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Agenda

Introduction und Motivation

Topology Optimization and Selective Laser Melting (SLM)

New needs

Conclusion and Outlook

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Topology Optimization

0,37 kg

46% CO2

Lattice structures

0,31 kg

37% CO2

Classic Design

0,8 kg

100% CO2

Source: Loughborough University, Econolyst Ltd.

Topology Optimization vs. Lattice structures design

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New needs for current optimization software

Mesh dependancy minimum feature sizes restricted

SLM process restrictions

SLM specific mechanical properties

Data and format handling

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338 elements 13 min 13 s

Mesh dependency in topology optimization

21.000 elements 41 min 47 s

2.100.000 elements Ca. 48 h

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Process restriction: Max. Overhang

Objective: Minimum build heigth

Material: AlSi10Mg

400 support structures

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Video: Compression test of f2ccz-type structure

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Agenda

Introduction und Motivation

Topology Optimization and Selective Laser Melting (SLM)

New needs

Conclusion and Outlook

© Fraunhofer ILT

Evaluation criteria AM Designguidelines

Lattice structuresdesign

Topologyoptimization

Functionaloptimization potential

Low Medium High

Resulting design Final design Final design Conceptual design

Simulation effort - Medium High

Automation Low Medium High

Traceability orintuitivity

High Low to Medium Low

Design verification Empirical formula Little empiricalformula available

FEM-based

Design approach comparison

Conclusion: Combination of all three approaches into one software tool

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SLM-specific design tool

Force

Celluar design space

Thermically optimized intersection for force transmission

Solid shell

Powder outlet

y

x

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New designs – Helicopter part

Material: 1.4404 (316L)

Fcc lattice structure

Weigth reduction: 50%

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Thank you!

Simon.Merkt@ilt.fraunhofer.de