Performance analysis of EDM electrode manufactured by direct metal laser sintering during machining of titanium alloy (Ti6Al4V)

Abstract

Recently, additive manufacturing based rapid tooling (RT) is gaining popularity in manufacturing industries because tool fabrication time and cost can be substantially reduced. In this regard, an experimental investigation is made to explore the machining performance of AlSi10Mg tool electrode manufactured through direct metal laser sintering and compared with commonly used copper and graphite electrodes in electro-discharge machining (EDM) of titanium alloy work piece. The influence of EDM variables on performance measures like material removal rate, tool wear rate, arithmetic mean surface roughness, surface crack density, white layer thickness and microhardness has been analyzed. The machined surface generated with the usage of different electrodes is inspected by scanning electron microscopy to study the surface integrity. It is observed that superior surface integrity can be attained utilizing AlSi10Mg DMLS electrode at lower setting of machining parameters. Energy dispersion X-ray spectroscopy analysis reveals that transfer of tool electrode elements onto the machined surface occurs along with increase in percentage of carbon and oxygen on the machined surface. From the X-ray diffraction analysis, it is found that metal carbides like titanium carbide and vanadium carbide are formed on the machined surface leading to increase in microhardness of the surface.

Keywords:

• Additive manufacturing
• AlSi10Mg electrode
• electro-discharge machining
• titanium alloy