overview of cold spray - sandia national laboratories ... · pdf filemfs cso 90714 dr. mark f....

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MFS CSO 90714 Dr. Mark F. Smith Cold Spray Workshop Albuquerque, NM July 14-15, 1999 Overview of Cold Spray Particle Velocity (m/s) > 325 > 350 > 375 > 400 > 450 > 475 > 500 > 425 200 0 100 300 400 500 Gas Pressure (psig) 200 250 300 350 400 Gas Temperature (ˆC) Air, 22 μm Copper 100 μm

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Page 1: Overview of Cold Spray - Sandia National Laboratories ... · PDF fileMFS CSO 90714 Dr. Mark F. Smith Cold Spray Workshop Albuquerque, NM July 14-15, 1999 Overview of Cold Spray Particle

MFS CSO 90714

Dr. Mark F. SmithCold Spray Workshop

Albuquerque, NMJuly 14-15, 1999

Overview of Cold Spray

ParticleVelocity (m/s)

> 325

> 350

> 375

> 400

> 450

> 475

> 500

> 425

2000 100 300 400 500

Gas

Pre

ssu

re (

psi

g)

200

250

300

350

400

Gas Temperature (ˆC)

Air, 22 µm Copper

100 µm

Page 2: Overview of Cold Spray - Sandia National Laboratories ... · PDF fileMFS CSO 90714 Dr. Mark F. Smith Cold Spray Workshop Albuquerque, NM July 14-15, 1999 Overview of Cold Spray Particle

MFS CSO 90714

250 m/s Cu

A “Cold” Process Technologyfrom Siberia

900 m/s Cu

Deposition Efficiency

CopperCoating Material

Iron Nickel Aluminum

After Alkimov, et al , 1990

400 500 600 700 800 900 1,000

0.80.70.60.50.40.30.20.1

0

Particle Velocity m/s

Page 3: Overview of Cold Spray - Sandia National Laboratories ... · PDF fileMFS CSO 90714 Dr. Mark F. Smith Cold Spray Workshop Albuquerque, NM July 14-15, 1999 Overview of Cold Spray Particle

MFS CSO 90714

Sandia Cold Spray System

HEATED GASGasInlets

Heater

TC

Gas Heater

PowderFeed

RobotManipulator

Page 4: Overview of Cold Spray - Sandia National Laboratories ... · PDF fileMFS CSO 90714 Dr. Mark F. Smith Cold Spray Workshop Albuquerque, NM July 14-15, 1999 Overview of Cold Spray Particle

MFS CSO 90714

Spray Ductile Metals, Cermets, Polymers

Active Braze Alloy AluminumAluminum BronzeCopper304 Stainless Steel420 Stainless Steel

Fe3Pt MolybdenumMonel80Ni/20CrNiCrAlYNiCr-Cr3C2

Polymer StelCarTantalumTinTitaniumWC-Co (nanophase)

Examples of Materials Successfully Deposited at Sandia

Page 5: Overview of Cold Spray - Sandia National Laboratories ... · PDF fileMFS CSO 90714 Dr. Mark F. Smith Cold Spray Workshop Albuquerque, NM July 14-15, 1999 Overview of Cold Spray Particle

MFS CSO 90714

Cold Spray vs. Air Plasma Spray

Plasma Sprayed Copper

Cold Sprayed Copper

100 µm

100 µm

• Superior Density• Less Oxide

Page 6: Overview of Cold Spray - Sandia National Laboratories ... · PDF fileMFS CSO 90714 Dr. Mark F. Smith Cold Spray Workshop Albuquerque, NM July 14-15, 1999 Overview of Cold Spray Particle

MFS CSO 90714

Some Exciting New Possibilities

• Avoid melting & solidification- Avoid thermally induced stress- Avoid undesirable phases- Avoid oxidation (deposit metals in ambient air!)- Preserve desired phases & chemistry- Preserve original grain size (nanocrystalline mat’ls)

• Low Porosity (>99% dense, as deposited)

• High thermal / electrical conductivity (>80% OFHC Cu)

• High Deposition Efficiencies (>98%)

• Recycle feedstock & process gas

• Work with highly dissimilar materials combinations

Page 7: Overview of Cold Spray - Sandia National Laboratories ... · PDF fileMFS CSO 90714 Dr. Mark F. Smith Cold Spray Workshop Albuquerque, NM July 14-15, 1999 Overview of Cold Spray Particle

MFS CSO 90714

New Possibilities, cont’d.

• Highly wrought material (high hardness / strength)

• Potential for high deposition rates

• Relatively insensitive to standoff, work up close (<1 cm)

• Minimal substrate heating

• May eliminate surface prep / masking

• Good as-sprayed surface finishes

• Non-circular spray patterns

• Potential for smooth surfaces

Page 8: Overview of Cold Spray - Sandia National Laboratories ... · PDF fileMFS CSO 90714 Dr. Mark F. Smith Cold Spray Workshop Albuquerque, NM July 14-15, 1999 Overview of Cold Spray Particle

MFS CSO 90714

Cold Spray Direct Fabrication

• Additively build net / near-net shapes directly from a computer

• Key technical challenge is focussing the spray stream

~ 1 mm FocusedStream for

Subsonic Flow

Do you want a print or a part?Print Build OK

OK

Do you want a Print or a Part?PrintBuild

Page 9: Overview of Cold Spray - Sandia National Laboratories ... · PDF fileMFS CSO 90714 Dr. Mark F. Smith Cold Spray Workshop Albuquerque, NM July 14-15, 1999 Overview of Cold Spray Particle

MFS CSO 90714

Example Applications

• Anti-corrosion (superior density, less oxide)

• Wear resistance (superior hardness & density)

• Metals on ceramics / glass

• High-alloy / specialty metals (preserve composition & phases)

• Plastic coatings without volatile organics

• Defect repair (minimal masking / heating, machinable)

• Direct fabrication

• Satellite structures (high conductivity, low residual stress)

Page 10: Overview of Cold Spray - Sandia National Laboratories ... · PDF fileMFS CSO 90714 Dr. Mark F. Smith Cold Spray Workshop Albuquerque, NM July 14-15, 1999 Overview of Cold Spray Particle

MFS CSO 90714

Reclaiming Parts & $$$

Unusable $150k GPSsatellite part reclaimed

with Cold Spray

• Low heat input• Low stress• Dense, machinable• High conductivity,

Page 11: Overview of Cold Spray - Sandia National Laboratories ... · PDF fileMFS CSO 90714 Dr. Mark F. Smith Cold Spray Workshop Albuquerque, NM July 14-15, 1999 Overview of Cold Spray Particle

MFS CSO 90714

State of the Art

• Technology ~ 10 years old

• Success with many metals, some cermets & polymers

• New materials / processing / manufacturing possibilities

• Considerable industrial interest

• Patented, but licenses available

• No commercial use yet

Page 12: Overview of Cold Spray - Sandia National Laboratories ... · PDF fileMFS CSO 90714 Dr. Mark F. Smith Cold Spray Workshop Albuquerque, NM July 14-15, 1999 Overview of Cold Spray Particle

MFS CSO 90714

Barriers to Commercial Use

Technical Issues:

• Process fundamentals poorly understood

• Cannot predict materials / parameters

• Reduce / eliminate expensive helium

• Nozzle fouling / optimization

Build-up in nozzle

Page 13: Overview of Cold Spray - Sandia National Laboratories ... · PDF fileMFS CSO 90714 Dr. Mark F. Smith Cold Spray Workshop Albuquerque, NM July 14-15, 1999 Overview of Cold Spray Particle

MFS CSO 90714

Barriers to Commercial Use

Manufacturing Issues:

• No commercial equipment / coating suppliers

• Need articulated robot compatible spray gun

• Lack of property data / field experience

• Need better fine powder feeders

Uneven deposition dueto uneven powder feed

Page 14: Overview of Cold Spray - Sandia National Laboratories ... · PDF fileMFS CSO 90714 Dr. Mark F. Smith Cold Spray Workshop Albuquerque, NM July 14-15, 1999 Overview of Cold Spray Particle

MFS CSO 90714

Understanding Critical Velocity

Raw Particle Velocity Distributions

0

20

40

60

80

100

200 400 600 800 1000 1200

0 %53 %95 %

No

rmal

ized

Co

un

ts

Particle Velocity (m/s)

DepositionEfficiency

1 2 3

19 µm Copper powder onto Aluminum

0

20

40

60

80

100

450 500 550 600 650 700 750 800

Dep

osi

tio

n E

ffic

ien

cy (

%)

Mean Particle Velocity (m/s)

3

2

11

2

3ExperimentPrediction

Page 15: Overview of Cold Spray - Sandia National Laboratories ... · PDF fileMFS CSO 90714 Dr. Mark F. Smith Cold Spray Workshop Albuquerque, NM July 14-15, 1999 Overview of Cold Spray Particle

MFS CSO 90714

Process Maps Guide Optimization

ParticleVelocity (m/s)

> 325

> 350

> 375

> 400

> 450

> 475

> 500

> 425

2000 100 300 400 500

Gas

Pre

ssu

re (

psi

g)

200

250

300

350

400

*DV�7HPSHUDWXUH��Û&�

Air, 22 µm Copper

Page 16: Overview of Cold Spray - Sandia National Laboratories ... · PDF fileMFS CSO 90714 Dr. Mark F. Smith Cold Spray Workshop Albuquerque, NM July 14-15, 1999 Overview of Cold Spray Particle

MFS CSO 90714

Models Guide Nozzle Design

dDdP

= CD ApM 2

2− 1

dVp

dt= D

m

Vp = particle VelocityD = Drag forcem = particle MassP = Pr essure

CD = Drag coefficientAp = Area of particleM = Mach number

max @ M = 2 = 1.4

(air)

(helium)

A*/A = Choke Point/Nozzle Exit Area Ratio(Axial Position measured from choke point)

Page 17: Overview of Cold Spray - Sandia National Laboratories ... · PDF fileMFS CSO 90714 Dr. Mark F. Smith Cold Spray Workshop Albuquerque, NM July 14-15, 1999 Overview of Cold Spray Particle

MFS CSO 90714

“Estimator” ver. 1.0 for Spray Parameters

Air Helium

Page 18: Overview of Cold Spray - Sandia National Laboratories ... · PDF fileMFS CSO 90714 Dr. Mark F. Smith Cold Spray Workshop Albuquerque, NM July 14-15, 1999 Overview of Cold Spray Particle

MFS CSO 90714

Understanding Particle Impact

1 km Asteroid Impacting Ocean

300 Gigatons TNT Equivalent (10x Peak of All Cold War Nuke’s)

Sandia Teraflops computer running CTH code100 million computational cells18 hr @ 91% capacity (8,192 of 9,000 processors)

Page 19: Overview of Cold Spray - Sandia National Laboratories ... · PDF fileMFS CSO 90714 Dr. Mark F. Smith Cold Spray Workshop Albuquerque, NM July 14-15, 1999 Overview of Cold Spray Particle

MFS CSO 90714

Computational Impact Model& Experimental Comparison

Predicted peak temp.of 1280 K is below the

melting point of Cu(1357 k)

Cu

Stainless Steel25 µm

4

3

2

1

0

- 1

- 2

- 3

- 4

Cu

StainlessSteel

t = 70 nst = 70 ns

X (microns)- 4 - 2 0 2 4

Y (

mic

ron

s)

Copper

Steel

Void

Temperature K

980

900

810

720

630

540

450

380

25 µm Cu Sphere into 304 Stainless at 600 m/s

Page 20: Overview of Cold Spray - Sandia National Laboratories ... · PDF fileMFS CSO 90714 Dr. Mark F. Smith Cold Spray Workshop Albuquerque, NM July 14-15, 1999 Overview of Cold Spray Particle

MFS CSO 90714

Summary

• New materials / processing / manufacturing possibilities

• Opportunity to be first to exploit market advantage

• Several pre-competitive barriers need to be solved

• Faster / cheaper / better to work together on pre-comp.

• Partners will gain access to best technology & new IP