The influence of tool quality on the machining of additive manufactured and powder metallurgy titanium alloys

Abstract

This study was carried out to investigate the impact the quality of the drill bits has on the machining behavior of additive manufacturing (AM) and powder metallurgy (PM) titanium alloys. Therefore, commercially available drill bits which typically reflect two extremes of drill bit quality were selected. The performance of coated carbide twist drills, typically recommended for the drilling of wrought titanium alloys was compared with that of high-speed steel (HSS) drills. The average torque value, specific cutting energy (SCE), and tool wear were used to evaluate the drilling performance of AM and PM titanium alloys. The results of drilling tests revealed the application of the coated carbide drill resulted in lower torque and SCE values, less flank wear, and lower build-up-edge (BUE) compared with the uncoated HSS drill bits for AM fabricated titanium alloys. However, the carbide drill appeared to offer negligible improvement over the uncoated HSS drill when employed with the PM fabricated titanium alloy. In spite of the improvement in the drilling performance offered by the carbide drills for the AM titanium alloy, TiB intermetallic particles (part of the AM titanium microstructure) contributed to the damage of the coated carbide drill which would limit the drill lifetime.

Optimization and experimental study on cathode structure of electrochemical machining Titanium alloy inner helix

“…Titanium alloy has many advantages of light weight, high speci c strength and good corrosion resistance, which has broad application prospects in light weapons equipment, aerospace, biomedicine and other elds [1][2][3][4][5][6][7]. However, the titanium alloy machining has problems such as sticking knife and heating makes low machining e ciency and poor surface quality, which seriously restricts the promotion and application of titanium alloy inner helix products [8,9]. Luckily, electrochemical machining (ECM) is a non-contact machining method based on the principle of anode dissolution.…”

Discrete wavelet transforms analysis of vibration signals for correlating tool wear in diamond turning of additive manufactured Ti-6Al-4V alloy

“…However, AM Ti-6Al-4V ELI alloy is often treated as difficult to machine due to tool wear and generally requires an appropriate selection of process parameters 17 . Ma et al explored the influence of the tool quality on machining of AM titanium alloy and powder metallurgy titanium alloy and found that AM titanium limits the lifetime of drill 18 . Colafemina et al 19 investigated the machinability of pure-titanium and Ti-6Al-4V suggesting ultra-precision diamond turning is a viable option for the finish of Ti-alloy and Ti-6Al-4V alloy.…”