friction stir welding of iron and nickel alloys-aws02 and nickel alloys.pdf(c) 2003 carl d. sorensen...

(c) 2003 Carl D. Sorensen

Friction Stir Welding of Friction Stir Welding of Iron and Nickel AlloysIron and Nickel Alloys

Carl D. SorensenCarl D. SorensenBrigham Young UniversityBrigham Young University


AcknowledgementsAcknowledgements

Tool materials and Tool materials and fabrication provided by fabrication provided by MegastirMegastir Technologies, a Technologies, a business alliance between business alliance between Smith International and Smith International and Advanced Metal ProductsAdvanced Metal ProductsWelding and analysis Welding and analysis provided by Russell Steel, provided by Russell Steel, Colin Sterling, and Yutaka Colin Sterling, and Yutaka Sato Sato


AgendaAgenda

BackgroundBackgroundCritical TechnologyCritical TechnologyRecent FSW Results in Fe and Ni alloysRecent FSW Results in Fe and Ni alloysPotential ApplicationsPotential ApplicationsGetting StartedGetting Started


Friction Stir WeldingFriction Stir Welding

Solid state joining processSolid state joining processRotating tool with small pin Rotating tool with small pin and large shoulderand large shoulderFrictional heating softens Frictional heating softens materialmaterialMaterial flows around pinMaterial flows around pinShoulder consolidates Shoulder consolidates material behind pinmaterial behind pin


Video DemonstrationVideo Demonstration


FSW AdvantagesFSW Advantages

Reduced distortion, compared to fusion weldsReduced distortion, compared to fusion weldsStable, repeatable processStable, repeatable processLower processing temperaturesLower processing temperaturesNo melting, so no solidification defectsNo melting, so no solidification defectsWrought, rather than cast, microstructureWrought, rather than cast, microstructure


FSW ApplicationsFSW Applications

Welding of deck plate for Welding of deck plate for highhigh--speed ferryspeed ferryWelding of extrusions for Welding of extrusions for automotive partsautomotive parts

Volvo seat backVolvo seat backFord steering linkFord steering link

Welding of highWelding of high--strength Al strength Al alloysalloys

Space shuttleSpace shuttleSolid rocket motorSolid rocket motorAircraftAircraft


FSW LimitationsFSW Limitations

Relatively simple geometryRelatively simple geometryUntil recently, only materials with low melting Until recently, only materials with low melting temperaturestemperatures

Tool material must be significantly harder than Tool material must be significantly harder than workpieceworkpiece at at elevated temperatureelevated temperature

Now, materials with high melting temperatures are Now, materials with high melting temperatures are weldableweldable

SteelSteelStainless SteelStainless SteelNickelNickel--based Alloysbased Alloys


Potential FSW Joint GeometryPotential FSW Joint Geometry

Butt Joint Lap Joint

Tee Joints Angle Joint


Critical Technology for HTMCritical Technology for HTM

SuperabrasiveSuperabrasive tool materialstool materialsComposite toolsComposite toolsWaterWater--cooled, temperature and force sensing cooled, temperature and force sensing tool holdertool holderComputerComputer--controlled machinecontrolled machine

Control based partially on tool load and tool Control based partially on tool load and tool temperaturetemperature


Tool MaterialsTool Materials

PCBN PCBN –– Compound of B and N Compound of B and N with diamond crystal structurewith diamond crystal structureProduced in highProduced in high--temperature, temperature, ultraultra--high pressure press (1450 C, high pressure press (1450 C, 870,000 870,000 psipsi))Outstanding material propertiesOutstanding material properties

Second in hardness only to diamondSecond in hardness only to diamondStable to 1200 Stable to 1200 °°CCChemically inert Chemically inert


Composite ToolsComposite Tools

WC ShankWC ShankPCBN InsertPCBN InsertHighHigh--strength locking strength locking collarcollarThermal barrierThermal barrier


Specialized Tool HolderSpecialized Tool Holder

Liquid cooling to protect Liquid cooling to protect machine spindle bearingsmachine spindle bearingsIntegrated thermocouple Integrated thermocouple to measure tool to measure tool temperaturetemperatureIntegrated force sensorIntegrated force sensor

Axial tool loadAxial tool loadLateral tool loadLateral tool load


ComputerComputer--Controlled MachineControlled Machine

44 inch travel44 inch travelForce capacity 10,000 Force capacity 10,000 kgfkgf Z, 5,000 Z, 5,000 kgfkgf XXCaptures weld process dataCaptures weld process dataMeasures tool temperatureMeasures tool temperatureCan control position, velocity, or forceCan control position, velocity, or force


FSW of HSLA SteelFSW of HSLA Steel


Recent FSW ResultsRecent FSW Results

0.125 in.0.125 in.1018 Steel1018 Steel

ThicknessThicknessAlloyAlloy

0.250 in.0.250 in.304 Stainless304 Stainless

0.089 in.0.089 in.Alloy 718Alloy 718

0.187 in.0.187 in.Alloy 600Alloy 600

0.125 in.0.125 in.Alloy 201Alloy 201

0.150 in.0.150 in.2507 Super Duplex2507 Super Duplex

1 in.1 in. 0.6 in.0.6 in.

• 40 CFH of Argon used in all welds


1018 Steel1018 Steel

Consistent weldsConsistent weldsOutstanding tool Outstanding tool life life ---- 80m (262 80m (262 feet)feet)79 plunges 79 plunges –– much much more than expected more than expected in productionin production


1018 Tool Life1018 Tool Life


304 Stainless304 Stainless

Large process windowLarge process windowOutstanding mechanical propertiesOutstanding mechanical propertiesAcceptable tool life Acceptable tool life –– 30 m (100 feet)30 m (100 feet)Weld ParametersWeld Parameters

Rotation: 400 rev/minRotation: 400 rev/minTravel:Travel: 3 in/min3 in/minLoad control: 9,000 Load control: 9,000 lbflbf


304 Process Window304 Process Window

800

900

1000

1100

1200

1300

Rot

atio

n sp

eed

(RPM

)

2 3 4 5 6 7Travel speed (IPM)

Preferentially etched region consists of only grain boundary attack.

Preferentially etched region consists of both heavily etched regions and G.B. attack.

There are holes at the advancing side of friction stir weld in the as-polished condition.


304 Microstructure304 Microstructure

Base materialBase material (500x) Center of DXZ

(500x)

Ret.

Ret. Adv.

Adv.


Sigma Phase in 304Sigma Phase in 304

500x

1000x

•Sigma phase observed in bands

•Also observed at grain boundaries between bands


304 Mechanical Properties304 Mechanical Properties

565698 (675)98 (675)55 (379)55 (379)Base MetalBase Metal

545495 (655)95 (655)51 (352)51 (352)400 RPM, 3 400 RPM, 3 IPMIPM

Elongation %Elongation %Ultimate Ultimate Tensile Tensile

Strength KSI Strength KSI (MPa)(MPa)

Yield StrengthYield Strength0.2 % offset 0.2 % offset KSI (MPa)KSI (MPa)

SampleSample

304 FSW 304 FSW

Transverse Tensile PropertiesTransverse Tensile Properties


304 Tensile Specimens304 Tensile Specimens


2507 Super Duplex Stainless2507 Super Duplex Stainless

Initial parameters onlyInitial parameters onlyRotation: 450 rev/minRotation: 450 rev/minTravel:Travel: 3.5 in/min (88 mm/min)3.5 in/min (88 mm/min)Load control: 7400 Load control: 7400 lbflbf


2507 Microstructure2507 Microstructure

Base material (200x) Center of DXZ (200x)

Adv.Ret.


2507 Phase Composition2507 Phase Composition

00 A1.5A1.5 A3A3R1.5R1.5R3R3

Up1.5Up1.5

Ferrite : RedAustenite : Green

R3 R1.5 0 A1.5 A3

Up1.5


2507 Mechanical Properties2507 Mechanical Properties


1919123 (845)123 (845)110 (762)110 (762)450 RPM, 3.5 450 RPM, 3.5 IPMIPM

Elongation Elongation %%

Ultimate Ultimate Tensile Tensile

StrengthStrengthKSI (MPa)KSI (MPa)

Yield Yield StrengthStrength

0.2 % offset 0.2 % offset KSI (MPa)KSI (MPa)

SampleSample

2507 FSW 2507 FSW Transverse Tensile PropertiesTransverse Tensile Properties


Alloy 201 WeldAlloy 201 Weld

Initial ParametersInitial ParametersRotation: 1000 rev/minRotation: 1000 rev/minTravel:Travel: 4 in/min (100 mm/min)4 in/min (100 mm/min)

After 12 in. of weldAfter 12 in. of weld

0.6 in.

•Tool previously used in alloy 718


Base material (500x) TMAZ (50x)

Adv. Ret.

Alloy 201 MicrostructureAlloy 201 Microstructure

DXZ (500x)


Alloy 201 Mechanical Alloy 201 Mechanical PropertiesProperties

505059 (406)59 (406)15 (103)15 (103)Base Metal (from Base Metal (from literature)literature)

343465 (448)65 (448)28 (193)28 (193)1000 RPM, 4 1000 RPM, 4 IPMIPM

Elongation %Elongation %Ultimate Ultimate Tensile Tensile

Strength KSI Strength KSI (MPa)(MPa)

Yield StrengthYield Strength0.2 % offset 0.2 % offset KSI (MPa)KSI (MPa)

SampleSample

Ni 201 FSW Ni 201 FSW Transverse Tensile PropertiesTransverse Tensile Properties



Initial ParametersInitial ParametersRotation: 450 rev/minRotation: 450 rev/minTravel: 2.25 in/min (56 mm/min)Travel: 2.25 in/min (56 mm/min)

After 6 feet of weld



Base material (100x) Center of Stir zone (100x)

Ret. Adv.



505092 (631)92 (631)38 (263)38 (263)Base MetalBase Metal(annealed (annealed condition)condition)

2727104 (719)104 (719)54 (374)54 (374)450RPM 2 450RPM 2 ¼¼IPMIPM

Elongation %Elongation %Ultimate Tensile Ultimate Tensile Strength KSI Strength KSI

(MPa)(MPa)

Yield StrengthYield Strength0.2 % offset KSI 0.2 % offset KSI

(MPa)(MPa)

SampleSample

Alloy 600 FSW Alloy 600 FSW Transverse Tensile PropertiesTransverse Tensile Properties


0.6 in.


Initial ParametersInitial ParametersRotation: 500 rev/minRotation: 500 rev/minTravel:Travel: 2 IPM2 IPM

After 4 feet of weldAfter 4 feet of weld

0.6 in.



Base material (500x) Center of DXZ (500x)

Adv.



4141130 (896)130 (896)67 (462)67 (462)Base Metal Base Metal

(Annealed, from (Annealed, from literature)literature)


(precipitation (precipitation hardened, from hardened, from

literature)literature)

1616143 (986)143 (986)97 (668)97 (668)500RPM , 2 IPM500RPM , 2 IPM

Elongation %Elongation %Ultimate Tensile Ultimate Tensile Strength KSI Strength KSI

(MPa)(MPa)

Yield StrengthYield Strength0.2 % offset KSI 0.2 % offset KSI

(MPa)(MPa)

SampleSample

Alloy 718 FSW Alloy 718 FSW Transverse Tensile PropertiesTransverse Tensile Properties


Achieving Success in FSW of Achieving Success in FSW of Iron and Nickel Based AlloysIron and Nickel Based Alloys

Use standard technologyUse standard technologyPCBN toolsPCBN toolsCooled, instrumented holderCooled, instrumented holderData acquisition systemData acquisition system

Use standard practicesUse standard practicesPublished in literature, conferencesPublished in literature, conferencesAvailable at MegaStir WorkshopAvailable at MegaStir Workshop

Optimize weld parametersOptimize weld parametersSpecific to material, thickness, joint geometrySpecific to material, thickness, joint geometry


ConclusionConclusion

FSW is feasible as a commercial process for iron FSW is feasible as a commercial process for iron and nickel alloysand nickel alloysTool life has been as high as 80 meters, and is Tool life has been as high as 80 meters, and is improvingimprovingMechanical properties of resulting welds are Mechanical properties of resulting welds are excellentexcellentAll systems are in place to assure successAll systems are in place to assure success

friction stir welding of iron and nickel alloys-aws02 and nickel alloys.pdf(c) 2003 carl d. sorensen...

Documents