Scratch-Induced Deformation Behavior of Wire-Arc Directed Energy Deposited α-Titanium.

Area of Science:

• Materials Science
• Mechanical Engineering
• Additive Manufacturing

Background:

• Commercially pure titanium (cp-Ti) is crucial for demanding applications.
• Directed energy deposition methods offer unique material processing capabilities.
• Understanding material behavior under stress is vital for performance optimization.

Purpose of the Study:

• To investigate the scratch response of WDED-processed cp-Ti.
• To analyze the influence of thermal history and build direction on wear properties.
• To correlate microstructural features with scratch resistance.

Main Methods:

• Progressive scratch testing (1-50 N) was performed on cp-Ti samples.
• Electron backscatter diffraction (EBSD) was used for microstructural analysis.
• Wear mechanisms and material recovery were quantified.

Main Results:

• Heterogeneous wear properties observed between top and bottom layers.
• Top layer showed higher material recovery (58%) and wear volume (5.02 × 10^-3 mm³) than the bottom layer (42% recovery, 4.46 × 10^-3 mm³).
• Higher kernel average misorientation (KAM) in the bottom layer (0.84°) impacted plasticity; no significant directional differences in friction (avg. 0.79-0.80).

Conclusions:

• WDED thermal gradient significantly influences cp-Ti scratch resistance and deformation.
• Microstructural variations, particularly grain structure and misorientation, dictate wear behavior.
• Findings provide insights for tailoring WDED processes for enhanced titanium component performance.