Friction Stir Processing of Aluminum Casting Alloys · PDF fileFriction Stir Processing of...
Transcript of Friction Stir Processing of Aluminum Casting Alloys · PDF fileFriction Stir Processing of...
Friction Stir Processing ofAluminum Casting Alloys:
Microstructure Manipulation/SurfaceComposite Fabrication
Ning Ning SunSunAdvisor: D. Advisor: D. ApelianApelian
Born in Qingdao, east coast ofChina (known for TsingTao Beer)
B.S. in MSE (July 2007), fromHefei University of Technology
M.S. Candidate ACRC(started September 2007)
Interests:• Western and Chinese music• Piano• Jogging
NING SUN
QINGDAO, CHINA
Outline
• BackgroundPrinciples, Applications, Challenges
• Objectives• Experimental Plan• Expected Outcomes• Schedule
Background
FSP is a relatively new processingmethod that was developed in 1997by R.S. Mishra et al* based on the
principles of friction stir welding (FSW-invented by TWI (UK) in 1991)
* High strain rate superplasticity in a friction stir processed 7075 Al alloy
Background
Credit: J.-Q.Su et al.
A rotating, non-consumable tool, comprising of a profiled pin and a larger shoulder plunges into the surface of the work-piece, and then travels along the work-piece
Background
Characteristics of FSP
• Solid-state• Thermo-mechanical in nature• Severe plastic deformation experienced
Background
Credit: I.Charit and R.S. Mishra
Grain size refinedfrom 200 µm to0.5 µm-12 µm.
Background
Grain Boundary Misorientation Angle Shiftsfrom a Low Value to a High One
a) b)
Credit: OIM result from W.M. Thomas et al
Background
High Strain Rate Superplasticity Achievedat Low Temperatures
Data of Mishra et al’s work in comparison with Xing’s
Background
Hardness Data (2014 Al alloy)
Credit: Y.J. Kwon et al
Background
Tensile Data (2014 Al alloy)
Credit: Y.J. Kwon et al
Background
Fatigue Data (A356)
Credit: By S.R. Sharma et al
Background
• Tool geometry• Tool wear• Overlapping• Microstructural stability
INFLUENCING PROCESSING PARAMETERS
Outline
• Background• Objectives• Experimental Plan• Expected Outcomes• Schedule
Objectives
Explore and Evaluate the Feasibility ofFriction Stir Processing in AluminumAlloys, Specifically To:
1. Manipulate the microstructure to refine or strengthen locally
2. Investigate the potential of FSP to form a particle-reinforcedzone in standard Al cast components, by mixing and creatingstrengthening particles, and establish optimum processingconditions; i.e., local composite fabrication via FSP
Experimental Plan
Alloys: work-piece material
• A356(6Si,0.2Fe,0.2Cu,0.1Mn,0.4Mg,0.1Zn,0.2Ti,other)
• A380(9Si,2.0Fe,3.0Cu,0.5Mn,0.1Mg,3.0Zn,0.5Ni,0.35Sn,other)
• A206(0.1Si,0.15Fe,4.2Cu,0.3Mn,0.3Mg,0.01Zn,0.2Ti,other)
Experimental Plan
FSP machine
HAAS Mill DrillCenter
> 10,000 RPM> 2000 IPM
Experimental Plan
Tool material:
Tool steel
Tool geometry:
Shoulder: 18mm Diameter Pin: Tilt angle ≈ 2.5-3 degree with
different tool shapes
Experimental Plan
Max diameter(mm)
Min diameter(mm)
Screw
Column 8 8 Y
Column 8 8 N
Taper 8 6 Y
Taper 8 6 N
Tool Shapes
Experimental Plan
Second Phase Particles Consideredfor Localized Composite Fabrication
> SiC
> TiC
> Cr3C4
> Al2O3
Experimental Plan
Processing:
• Confirm microstructure evolution during FSP
• Surface composite fabrication via FSP
Experimental Plan:microstructure evolution
Confirm Microstructure Evolution During FSP:
500, 800, 1250, 1750, 2000 (rpm)
100, 150, 200 (mm/min)
Experimental Plan:composite fabrication
Particle-reinforced Zone Developed by:
• Mixing-in strengthening particles
• Forming strengthening particles by in-situ chemical reactions
Experimental Plan
Mixing-in Strengthening Particles:
I. Filling into the groove on the surface of the work-piece
II. Painting slurry onto the surface of the particle-reinforced zone
III. Injecting powder into the FSP zone
Experimental Plan
Forming Strengthening Particles by in-situChemical Reactions:
I. Alloy + Reactant + Catalyst Particles + Secondary product
II. Pin tool + Reactant + Catalyst Particles + Secondaryproduct
III. Reactant (1) + Reactant (2) + Catalyst Particles + Secondaryproduct
Experimental Plan
FSP Parameters for Surface Composite Fabrication:
500 rpm, 800 rpm
20 mm/min, 80mm/min
H 1mm, 1.7mm, 2.3mmH
Outline
• Background• Objectives• Experimental Plan• Expected Outcomes• Schedule
Expected outcomes
Microstructure Evolution During FSP
Grain size refined from several hundred µm orseveral ten µm … to 0.5 µm-12 µm
Grain boundary misorientation angle shiftsfrom low to high
Enhanced mechanical properties
Expected outcomes
Surface Composite Fabrication via FSP
Particle reinforced zone is created via FSP
Structural integrity at localized interface
Enhanced mechanical properties
Schedule
Sep '07-Dec'07
Jan '08-May'08
Jun '08-Dec'08
Jan '09-March '09
April '09-June '09
Critical Lit Review (I) (I)
Project Planning (I)
Finalize Exp. Plan (I) (I)
Execute Exp. Part I (II) (II)
Execute Exp. Part II (II) (II) (II)
Modeling (III) (III) (III)
Thesis Write-up (IV)
Thesis Defense (IV)
Thank you for theopportunity andyour attention