Investigation of the influence law of EDM electrical parameters on the recast layer in titanium alloys

doi:10.16731/j.cnki.1671-3133.2024.06.015

Abstract

Abstract: The recast layer formed on the surface of a workpiece after Electrical Discharge Machining (EDM) significantly impacts the surface integrity and mechanical properties of the workpiece.The Recast Layer Thickness (RLT) has become an important process parameter in EDM,especially critical in EDM of titanium alloys. The RLT is primarily affected by electrical parameters. Taking the titanium alloy Ti6Al4V as a case,first,the influences law of main electrical parameters (peak current,pulse duration,duty cycle,and gap voltage) on the RLT were discussed.Furthermore,based on the impact of the recast layer on surface roughness and material removal rate,an optimized electrical parameter combination was conducted considering multiple objectives including RLT,surface roughness,and material removal rate. Finally,the principles for electrical parameter selection were summarized in accordance with different RLT requirements. Experiments verified that while the optimal electrical parameter combination achieved a thin RLT and low surface roughness while realizing an improved 2.76 times material removal rate.

Key words: Electric Discharge Machining(EDM), titanium alloy, recast layer, orthogonal test, gray correlation analysis method

CLC Number:

TG661

WANG Zehan, ZHOU Ming, SONG Zixiong, ZHAO Meng, XU Pei, XIN Fangqing. Investigation of the influence law of EDM electrical parameters on the recast layer in titanium alloys[J]. Modern Manufacturing Engineering, 2024, 525(6): 111-121.

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