Characterization of electric discharge machining of titanium alloy utilizing MEIOT technique for orthopedic implants

Abstract

In this research work, medical grade titanium alloy Ti4Al6V was electric discharge machined with an objective of attaining mirror finish for orthopedic implants. Experiments were conducted by varying tool materials, discharge current, pulse on time and pulse off time whereas the responses chronicled are material removal rate, electrode wear rate and surface roughness. The aluminium (A), copper (C) and aluminium alloy reinforced with graphite particles of various weight percentage (5-A1,10-A2,15-A3) were used as tool materials. The composites were fabricated using stir casting technique. The findings showed that the titanium alloy machined with A1 composite tool offers the highest MRR, the C tool has the lowest EWR, and the A2 composite tool results in good surface finish. The surface of specimens produced using A1 tool exhibits poor surface quality owing to the eczema surface. Specimens machined with the C tool have a remelted layer, pockmarks, and an uneven fusion structure, which were not present in specimens machined with the A2 tool. MOORA-ELECTRE Integrated Optimization Technique (MEIOT) was applied to select the best parametric combination and the best electrode material.

Keywords

• composite tools
• hybrid optimization
• orthopedic application
• electric discharge machining
• surface morphology