Feasibility Study on Machining of Niobium to Achieve Nanometric Surface Finish

Niobium has good superconducting properties at cryogenic temperature, due to which it is used for making superconducting radio frequency cavities of particle accelerators, superconducting magnets of MRI scanners, and nuclear magnetic resonance spectrometer equipments. Having high hardness value, niobium is considered to be difficult to machine material. Hence, machining with the optimal cutting parameters becomes a necessity. The focus of this experimental work is to investigate the machining of niobium material by employing a cubic boron nitride tool to obtain a good surface quality. Taguchi methodology have been uses to find the  optimum value of machining parameters, i.e., feed rate, spindle speed, and depth of cut. From the results, the effects of input parameters are studied, and with the help of optimized parameters the surface roughness of  107 nm and surface waviness of 0.55 µm is achieved.