Additive Manufacturing Technology Overview PowerPoint Presentation

Additive Manufacturing Technology Overview

Mike

Klecka

United Technologies Research Center

East Hartford, CT

June

18, 2014

Presentation Overview

Additive Manufacturing TechnologyComparison of Additive Manufacturing MethodsTypical Post Processing RequirementsMultiple Material DesignsAdditive Manufacturing with Cold SpraySuitability of Parts for Additive ManufacturingDesign and Redesign for AMAM Process Selection

2

Increasing Pressure on Manufacturing

Requirements

Shorter time to market

Higher performance requirements

Increased product life, durabilityReduced weightLower costHigher yield and qualityImproved energy efficiencyLess waste, environmentally friendly

Potential benefits from additive manufacturing

Reduced machining time, energy, & costReduced material consumptionMaterial solutions and combinations not otherwise possibleIncreased part complexity

3

Additional

challenges

Increasingly complex part geometries and systems

Expanded material options

Manufacturability concerns

Slow adoption of new techniques

Qualification of new processes

Additive Manufacturing Overview

Additive manufacturing is broadly defined as the addition of functional material to a substrate, after which is either incorporated into the substrate as the finished part or is separated from the substrate to yield a free standing partAdded ribs to a sheet or panel for stiffeningAdded lugs to a tube for mounting3D printing of entire components on a build plateMajority of techniques utilize powder feedstockSome use wire, sheet, or strip stock

Non-Powder Based Techniques

Laser wire feed, EB wire, ultrasonic, laminated objectAdvantages – High deposit rates, low cost feedstockDisadvantages – Poor part tolerance, required post machining, moderate property potential

Powder Bed TechniquesLaser powder bed, DMLS, EBMAdvantages – Small features, tight tolerance, fully inert environment Disadvantages – Low deposition rate, limited part size, single material

Powder Deposition Techniques

Cold spray, LENS, Laser applied powderAdvantages – Moderate part sizes, in situ alloying, moderate deposition rates, dissimilar materialsDisadvantages – Lower dimensional accuracy, less tolerance control

Build Core

Added Material

4

DMLS, LPB, EBM, powder bed fusion

Potential for widest variety of geometry

Limited to one materialLow deposition rates (0.05 - 0.5 kg/hour)Part size limited by dimensions of powder bedAdvantages – Small features, tight tolerance, high geometric fidelity, fully inert environment Disadvantages – Stress relief & heat treatment often required, slow build rates, limited part size

Powder Bed

LENS, laser applied powder (LAP)

Multiple build directionsMultiple material depositionModerate deposit rates (0.5 – 1 kg/hour)Advantages – Moderate geometric fidelity, shield gas environment, cladding/repair/resurfacingDisadvantages – Moderate feature size, moderate property potential, gravity concerns with build direction

Laser Powder Injection

Laser Applied Powder

5

Comparison of Additive Manufacturing

http://en.wikipedia.org/wiki/Selective_laser_sintering

Comparison of Additive Manufacturing

High plastic work during deposition

High deposition rates (3 – 15 kg/hour)

Limited to line-of-sight processingLower geometric fidelityAdvantages – Solid state processing, good mechanical properties, multi-material, bonding of dissimilar materials

Cold Spray

Laser/EB Wire Additive

LAW, MIG, EB Wire

High rates (3 – 10 kg/hour)Low cost feedstockLow feature toleranceModerate property potential

Ultrasonic & Laminated Object

UC, UAM, LOM

High build ratesSheet, strip feedstockLimited geometrySolid state

Granular Material Bonding

Powder bed inkjet & binder jetting

3D printing sand, casting molds/coresPlaster based printing (PP)Low material properties, low costSintered metal, polymer, & ceramics

6

ASM Handbook, Vol.6A, Welding Fundamentals and Processes (2011)

Conductive ink printing, conformal surfaces

Potential

for wide variety of geometriesExcellent resolution depending on techniqueMultiple material depositionMicro cold spray

Direct Write

Thermoplastic-based (neat or filled)Layer-by-layer depositionExtrusion & shrinkage limits high resolutionCapable of complex geometries and low density coresMultiple material deposition, limited properties

Fused Deposition

Actuators, Motors & MEMS

Sensors & Arrays

SLA, Large Area

Maskless

Photopolymerization

(LAMP)Ceramics and polymers, UV curing materialsComplex geometries with good resolutionRestricted material selection, resin is often expensive

Stereolithography

Prototype

parts

Cores

7

Comparison of Additive Manufacturing

http://en.wikipedia.org/wiki/Stereolithography

http://en.wikipedia.org/wiki/Fused_deposition_modelling

Metal Based AM Comparison

8

Deposition Rate

Feature Resolution

Laser Powder Bed

Electron

Beam Powder Bed

Laser Applied Powder

Wire Feed Techniques

Cold Spray

Ultrasonic Fabrication

AM technology publicizes less raw material waste compared to conventional machining

Cold Spray:

Deposition efficiency and overspray can vary significantly based on material

Laser Applied Powder:

Capture rates between 40% and 80%, depending on process conditions

Powder Bed:

Un-sintered powder has potential to be reclaimed and reused - gives rise to additional questions of repeatability and quality

Wire Feed:

C

aptures better than 90%, similar with ultrasonic; often requires post machining

Common constraints for each AM technique

Part Size:

Powder beds limited in size, typically less than 12 inches, while wire feed can accommodate 10 foot long sections or more

Build Speed:

Powder beds often take many hours (often more than 24 for large structures), LAP may take up to 12 hours or more, wire feed less than 6 hours

Material Properties:

Melting processes result in strength similar to cast, solid state processes (cold spray & ultrasonic) may be better

Often overlooked aspect of AM: Post processing requirements

Stress relieving via heat treatment to prevent part distortionDue to rapid cooling rates, AM parts often contain large residual stressesConducted while part remains affixed to build plateRemoval of part from build plate, typically via EDMHeat treatment to reach required microstructure and mechanical propertiesAs deposited, AM parts often resemble cast microstructuresDirectionality is common, with grain structures oriented in the build directionMay require HIP to reduce porosity and improve densityHomogenization and solution treatment to reduce grain orientationHardening/precipitation/strengthening/quench/temper heat treatment, as requiredFinish machining to meet required geometry and tolerancesPeening, grit blasting, and tumbling to improve surface finishInspection for defects/flaws

Example: Powder Bed

9

Typical Post Processing Requirements

Part distortion in laser applied powder after removal from build plate

Multiple Material Designs

Additive techniques offering multiple material solutions:

Injected powder laser additive (LAP, LENS, etc.)Cold spray depositionUltrasonic consolidationMultiple material part fabricationWeight reductionLight weight base/core materialHard, wear resistant surfaceIntegrated component designsPotential for advanced materials

10

Cold spray tensile

sample, deposited on steel mandrel with engineered release layer

Potential for buildup of uniform section possible through proper gun manipulation

More complicated geometries possible through mandrel concept

Level of Finish Machining Required

Mandrel design

Material usedDimensional requirementsAccuracy of spray path

11

Additive Manufacturing with Cold Spray

Support with sharp drop-off

CS deposit

Component: Structural mount

Process: Cold spray additive manufacturing

Structural modeling & optimization indicate preferred geometry

Critical factors:

Material properties and layout

Process parametersStructural performanceGeometric process characteristics…

Case Study: Optimization of Additively Manufactured Structural Mount

Structural mount

12

θ

1

Substrate is flat

θ

2

Substrate drops off

Trapezoidal cross section

Additive Manufacturing Process Dependence

Different outcomes by process and properties

Design for the cold spray process using removable mandrel

Design for direct metal laser sintering (DMLS) powder bed process

Design conception for the laser applied powder (LAP) process

13

Suitability of Parts for Additive Manufacturing

Existing clear business case for using AM Many processing steps, intensive machiningAM saves time, has less raw material wasteNo existing business case, but redesign could create oneCurrent design more expensive with AMRedesigned part could be more cost effective using additive techniqueConsolidation of multi-part assembly into single componentNo existing business case, low likelihood that redesign could impactLow cost conventional processing (e.g., stamping)Satisfactory performanceHigh part volumes required

AM makes sense for some, but not all components

Redesign may improve the performance independent of cost

14

Redesign for Additive Manufacturing

Conventional manufacturingWell-established limits in feature shape and complexityCastingForgingMachiningHigher cost often associated with feature complexity and low weightAdditive manufacturingNew areas of design spaceOften no penalty for more complexityPossible lower cost associated with higher feature complexity and lower weightRedesign for AM requires creativity and new ways of thinking

Parts suited for additive manufacturing may look different than traditional counterparts

15

Additive Manufacturing Technique Selection

Some key considerationsSize of partGeometric toleranceSurface finishThroughputGeometric complexityFeature sizeSingle- or multi-materialMechanical propertiesMicrostructure…AM technologies are rapidly evolving

16

Deposition Rate

Feature Resolution

Laser Powder Bed

Electron

Beam Powder Bed

Laser Applied Powder

Wire Feed Techniques

Cold Spray

Ultrasonic Fabrication

Thank You

17