Research on an EDM-based unitized drilling process of TC4 alloy

Affiliation of Author(s):机电学院

Journal:INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY

Key Words:EDM drilling EDM/ECM combined process TC4 alloy Recast layer

Abstract:To reduce the recast layer and cracks formed during the small hole, electrical discharge machining (EDM) of the TC4 alloy, negative polarity EDM, and electrical discharge machining/electrochemical machining combined process (EDM/ECM) were carried out. The machining efficiency, the recast layer, and the cracks were studied. The experimental results showed that when compared with common positive polarity EDM under the specific processing condition, the recast layer of the negative polarity EDM decreased by 65% in thickness but the material removal rate (MRR) decreased by 31%. In EDM/ECM, MMR was 18% higher than the positive polarity EDM, and the majority of the recast layer and the cracks were removed. However, issues including the low efficiency occur during the penetration period. The following paper analyzed the causes of these problems and proposed a novel unitized hole drilling process. In this unitized process, EDM/ECM was initially used and then converted to negative polarity EDM with external flushing water during the penetration period. The general machining efficiency of a single hole increased by 73% over conventional EDM/EDM. Furthermore, only a 7-mu m thick recast layer remained at the hole's outlet, with no obvious cracks found.

ISSN No.:0268-3768

Translation or Not:no

Date of Publication:2018-07-01

Co-author:陶筱天,Qiu Mingbo,tzj,Lida Shen

Correspondence Author:tzj,lzd

Date of Publication:2018-07-01