Experimental investigation and machining analysis of Mg/TiC composites during EDM
Dharmeswar Dash, Devarasiddappa Devarajaiah, Santosh Kumar Dash, Sutanu Samanta, Ram Naresh Rai
Quarterly No. 1, 2024 pages 9-16
DOI: https://doi.org/10.62753/ctp.2024.02.1.1
keywords: magnesium alloy, TiC, electrical discharge machining, surface quality, material removal rate, surface roughness, analysis of variance
abstract Electrical discharge machining (EDM) is one of the prominent non-conventional machining processes used to machine metal matrix composites. Mg/TiC composites are found in many industrial applications and conventional machining of the same is highly challenging. This paper aims to study the machinability analysis of Mg/TiC composites using EDM with pulse-on time (Ton), pulse-off time (Toff) and input current (I) as the process variables with the material removal rate (MRR) and surface roughness (SR) as the performance measures. Stir cast Mg-alloy reinforced with TiC (0, 5, 10, 15 and 20) by weight was used as the workpiece. The EDM experiments were conducted as per L25 orthogonal array (OA) and the results were analyzed to study the effect of the process variables on MRR and SR. The parametric study showed that SR increases linearly with Ton and is attributed to larger craters produced at a higher pulse energy. MRR was also observed to grows with the rise in Ton as more material melts due to high-intensity pulses. As per the ANOVA results, Ton was found to be the most influential process variable affecting SR and MRR with a 79% and 34% contribution, respectively. Surface morphology investigations using SEM micrographs revealed the presence of globules and sphere-shaped metal deposits and were found responsible for increased SR.