Statistical Analysis of Burr Formation in Low Speed Micro-Milling of Titanium Alloy (Ti-6Al-4V)

Abstract

Increasing demand of micro scale components in the industry of electronics, aerospace, automotive and biomedical has opened up a door where there is strong research potential in the field of micro machining. Titanium based alloys are the most suitable to be used as workpiece material for different applications in these industries. Out of actual titanium usage, Ti-6Al-4V accounts for more than 45%. On one side, it exhibits strong properties like biocompatibility and excessive strength to light weight ratio while on the other side, it is very hard to machine due to low thermal conductivity and high chemical reactivity. In this research, feed per tooth, conventional cutting speed and depth of cut are considered as machining parameters and their effect on burr formation is analyzed through statistical technique of analysis of variance to determine key process variables. Results showed that feed per tooth is the most dominant factor causing burr formation (81% contribution ratio), cutting speed is second dominating factor (6% contribution ratio) and impact of depth of cut is negligible (1% contribution ratio). Results also show that micro-milling machining process is sensitive to residual effect (12% contribution ratio). Machining at optimum process parameters showed minimum burr formation. Although conventional speed micro-milling of titanium alloy would take more time than high speed micro-milling but it would give better results in terms of minimization of burr.