Chip formation characteristics in the machining of titanium alloys: a review

Abstract

Titanium alloy is widely used in fuselage and gas turbines of aircraft with its high specific strength, strong corrosion resistance and excellent thermal stability. However, titanium alloy is one of the extremely difficult to machining materials. One typical feature in the machining of titanium alloy is the saw-tooth chip formation, which decreases the tool-chip contact area and generates the cyclic cutting force. Consequently, the fluctuation and chattering increase sharply in the process of cutting, and the cutting temperatures become very high, which limits the material removal rate and aggravates tool wear. Therefore, the primary purpose of this paper is to investigate the saw-tooth chip formation mechanism and its interaction with cutting tool. The survey of existing works shown that the main tool chip interface reaction in machining of titanium alloys are diffusion, adhesion, and abrasion. The relationship between the chip morphology and the cutting speed, feed rate, as well as machining conditions have been investigated. Besides of Ti-6Al-4V alloy, other titanium alloys, such as β titanium alloy, and the non-traditional machining method also have been investigated.