A critical review of advanced techniques to improve machining of titanium alloy (grade 5)

Abstract

Sea to space applications necessitate advanced materials to fulfill diverse requirements, including Titanium and its alloys, particularly Grade 5 (Ti-6Al-4V alloy). Exhibiting remarkable properties such as high heat resistance, low thermal conductivity, low weight ratio, and minimal corrosiveness, Titanium Grade 5 holds immense potential for applications in aerospace, biomedical, automotive, and military sectors. However, its full utilization is impeded by challenges encountered during machining. This paper provides an overview of the difficulties faced in machining Titanium Grade 5 and emphasizes the ongoing search for the optimal tool-material combination. The paper discusses the properties influencing machinability, such as thermal conductivity, chemical reactivity, elastic modulus, hardness, strength, work hardening, and the effects of temperature on Ti-6Al-4V alloy. The review emphasizes the various techniques employed to enhance machining efficiency, including dry cutting, flood cooling, minimum quantity lubrication, high-pressure coolant environment, cryogenic environment, solid lubricants, and hot machining. While the best pairing remains elusive, significant progress has been made in the machining of titanium alloys, showcasing various evolving techniques and methodologies aimed at enhancing the material's usability in diverse industrial applications.