Process Optimization on Trepanning Drilling in Titanium Alloy Using a Picosecond Laser via an Orthogonal Experiment

Area of Science:

• Materials Science and Engineering
• Manufacturing Processes
• Laser Machining

Background:

• Titanium alloys like TC4 are crucial in aerospace and medical industries.
• Efficient and precise micro-hole drilling is essential for manufacturing components from these alloys.
• Existing laser drilling methods require optimization for speed and quality.

Purpose of the Study:

• To optimize the picosecond laser trepan drilling process for titanium alloy TC4.
• To analyze the influence of key laser parameters on micro-hole quality (diameter, taper, roundness).
• To reduce overall processing time for micro-hole fabrication.

Main Methods:

• Utilized picosecond laser trepan drilling on TC4 titanium alloy.
• Employed an L25 (5^6) orthogonal array for experimental design.
• Investigated the effects of laser power, defocusing distance, scanning speed, and number of scans.
• Applied mean response and range analyses for parameter impact evaluation.

Main Results:

• Scanning speed and laser power significantly impact micro-hole diameters.
• Defocusing distance is critical for controlling micro-hole taper.
• Laser power and defocusing distance influence roundness, with laser power being key for inlet roundness.
• Number of scans showed a weaker correlation with hole quality metrics.

Conclusions:

• Identified optimal parameters for picosecond laser trepan drilling of TC4: 90% laser power (30 W), -0.2 mm defocus, 27 mm/s scanning speed, and 15 scans.
• The optimized process enhances micro-hole quality (diameter, taper, roundness).
• Achieved significant reduction in processing time through parameter optimization.