The performance of graphene powder-mixed WEDM for machining high-volume-fraction SiCp/Al (45 vol%)

The 45 vol% SiCp/Al composite features high hardness and brittleness, leading to low machining efficiency and poor surface integrity in wire electrical discharge machining (WEDM). Graphene composite powder was introduced into dielectric fluid to optimize discharge conditions. Concentration-gradient and single-factor tests demonstrate that graphene, owing to its field emission and high thermal conductivity, raises material removal rate (MRR) by 13.28% and reduces surface roughness (Ra) by 27.26%. An L16(44) orthogonal experiment was carried out, and a multi-criteria evaluation model was established integrating grey relational analysis and analytic hierarchy process. Multi-objective optimization indicates the power transistor number dominates overall performance. Grey relational analysis yields optimal parameters: pulse width 18 μs, duty ratio 1:4, power tubes 4 and wire speed 3. Validation verifies this set balances MRR and Ra: Ra drops by 14.64% vs. the maximum-MRR group, while MRR rises by 35.19% vs. the minimum-Ra group.