Microstructural analysis of variable iron–molybdenum reinforcement in copper-based composite castings using microwave energy

A novel processing route involving microwave hybrid heating (MHH) was successfully used to cast metal matrix composites of Cu-based material. The composite casting of Cu+10%Fe, Cu + Fe10% + 5%Mo, Cu + Fe10% + 10%Mo, and Cu + Fe10% + 15%Mo were developed in a domestic microwave oven with power of 900 W and 2.45 GHz frequency. The optimum microwave radiation exposure time of 7 min was required to completely melt the pure copper powder. However, the addition of Fe–Mo reinforcement reduced the exposure time to 5 min (min) for the Cu +10%Fe+15%Mo composite cast. The mechanical and metallurgical properties of the prepared casts were studied. Only 0.62% copper oxide phase was detected in the pure copper cast samples. While, XRD analysis confirms the presence of various other phases in the composite cast samples, such as Cu 64 O, Fe 2 O 3 , and MoO 2 .The microstructure of the cast samples shows regular, roughly hexagonal grain growth that resembles cellular proliferation. These results indicate a decrease in grain development and recrystallization after the addition of Fe–Mo to Cu. The microhardness of the reinforced composite of Cu + Fe10% + 15%Mo was 130.9 ± 6.54 HV 0.3 , which is 2.12 higher than that of microwave-processed pure Cu cast. • Microwave Hybrid Heating (MHH) was successfully utilized to cast Cu-based metal matrix composites in a domestic microwave oven (900 W, 2.45 GHz). • Pure copper required 7 min of microwave radiation for complete melting. Addition of Fe–Mo reinforcement reduced exposure time to 5 min for the Cu + 10% Fe + 15% Mo composite. • Regular, roughly hexagonal grain growth resembling cellular proliferation. Addition of Fe–Mo resulted in decreased grain development and recrystallization. • This technique offers an energy-efficient and time-saving alternative for composite fabrication.