Study on the Material Erosion Mechanisms in WEDM of Refractory High Entropy Alloys via Selective Corrosion

doi:10.3901/JME.2025.13.440

Abstract

Abstract: Refractory high entropy alloys (RHEAs) usually exhibit complex and variable microstructures and constituent phases, as well as severe element segregation, making it difficult to clarify the material erosion mechanism during wire electrical discharge machining (WEDM). Due to the differences in element enrichment for constituent phases and the presence of porous recast layer on the machined surface, selective corrosion usually occurs on the machined samples. Based on this characteristic, different durations of electrochemical corrosion treatment are performed on the WEDMed W₁₅(TaVZr)₈₅ RHEA with multi-phase structure. The surface morphology with different corrosion time and the content and distribution of constituent elements at different depths beneath the machined surface are investigated and analyzed. The V and Zr elements are found to migrate significantly to the recast layer during WEDM. According to the correspondence between constituent phases and enriched elements, as well as the differences in physical properties and crystal structure stability of constituent phases, the material erosion mechanism in which minor phases tend to be preferentially eroded during WEDM is revealed. The present work provides a potential strategy for the mechanism investigations on the material erosion and recast layer formation for EDMed metallic materials.

Key words: refractory high entropy alloy, WEDM, material erosion mechanism, electrochemical corrosion

CLC Number:

TG661

ZHANG Jingsai, YUE Xiaokang, CHEN Shunhua. Study on the Material Erosion Mechanisms in WEDM of Refractory High Entropy Alloys via Selective Corrosion[J]. Journal of Mechanical Engineering, 2025, 61(13): 440-448.

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