A sustainable and energy efficient approach for development of electrically conductive materials and their characterizations

In this study, composite castings of electrically conductive materials were prepared using electromagnetic energy of frequency 2.45 GHz. Three separate sets of castings were produced inside the domestic microwave applicator cavity, with reinforced compositions of up to 15% in steps of 5% for each composite cast (copper (Cu) + 5% molybdenum (Mo), Cu + 10% Mo, and Cu + 15% Mo). A microwave radiation exposure time of 12 min was required for the complete melting of pure copper powder. However, the addition of Mo reinforcement caused a reduction in exposure time to 11.33 min (min) for the Cu-15% Mo composite cast. The formation of different phases was revealed by the X-ray diffraction analysis of the cast samples. Only a 0.92% copper oxide phase was detected in the pure copper cast samples. The composite cast samples exhibited peaks corresponding to Cu64O, Cu6Mo5O18, and MoO2. Microstructure analysis demonstrated that the grains grew in an equiaxed manner with a uniform dispersion of the reinforcements. The maximum microhardness achieved is 99.2 ± 4.99 Hv for Cu + 15% Mo which is 1.66 times better than microwave-cast copper sample.