Surface Integrity Associated with SiC/Al Particulate Composite by Micro-Wire Electrical Discharge Machining

Abstract

It is difficult to have high accuracy and low surface roughness in processing of metal matrix composites (MMCs). Micro-wire electrical discharge machining (micro-WEDM) has no obvious cutting force in processing because there is no direct action between tool electrode and workpiece, which makes micro-WEDM complete the machining of MMCs with high hardness and high strength. However, the recast layer can be formed with damages on machining surface in micro-WEDM process. Therefore, to resolve these problems, this paper highlights analysis of the surface characteristics of SiC/Al particulate MMC in micro-WEDM process. In addition, the characteristics of recast layer with different discharge energy are analyzed. And the removal process of ceramic particles in the composite is thermal spalling process, which is proved using surface morphology of SiCp/Al MMC by micro-WEDM. Finally, to reduce the thickness of recast layer and improve surface integrity of SiCp/Al2024 MMC by micro-WEDM, a multicutting experimental is performed and the machined surface with 0.774 µm in surface roughness and 3 µm in recast layer thickness are obtained.

Keywords:

• Micro-wire electrical discharge machining
• Multicutting
• Recast layer
• SiC/Al particulate composite

Notes

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