## 3 Results and Discussion
### Tensile Strength Analysis  
The effect of different reinforcements on copper alloy-based hybrid metal matrix composite on tensile stress-strain behavior is analyzed under ambient conditions. The tensile properties of the developed hybrid composites are analyzed in comparison with the base copper C87600 alloy matrix. The typical image of the tensile specimens before and after their fracture is presented in Figure 12. The variation of tensile strength of the Copper hybrid composite with the content of reinforcement is presented in Figures 13 and 14. Both the ultimate tensile strength (UTS) and yield strength of the hybrid composites were measured and observed to be increased with an increase in the reinforcement content. The physical and mechanical properties of the reinforcement materials significantly influence the tensile strength of the developed material. The graph shows that the ultimate tensile  
Figure 11: Pyramid indentation during Vickers micro-hardness test. Figure 10: Variation of Vickers micro-hardness Cu alloy and Cu-(3, 6, 9) wt.% WC-Gr hybrid composites. and yield strength of the copper C87600 alloy is 371.5 MPa and 243.6 MPa, respectively. The addition of SiC ceramic particulate by 3, 6, and 9 wt.% along with 1 wt.% graphite increased the yield strength by 6.5, 13.7, and 24%. In contrast, the ultimate tensile strength is increased by 4.5, 13.4, and 26%, respectively, compared with the base copper C87600 alloy. It was found that the Cu-9%SiC-1%Gr hybrid composite displayed maximum yield strength of 303 MPa and ultimate tensile strength of 467 MPa. The ultimate tensile strength and yield strength of the Cu-9%SiC-1%Gr hybrid composites are increased by 26% and 24%, respectively, in comparison to the base copper alloy. Figure 12: Tensile specimen before and after tensile test. Figure 13: Variation of yield strength and ultimate tensile strength of Cu alloy and Cu-(3, 6, 9) wt.% SiC-Gr hybrid composites. In the present study, Cu-9%WC-1%Gr showed the highest tensile strength among the developed composites. It is important to note that the tensile strength of WC-reinforced composites had shown relatively higher strength than the SiC-reinforced hybrid composites may be due to the better mechanical properties of the reinforcement used [26]. The ultimate tensile strength and yield strength of the materials increased by 30% and 28%, respectively, for the Cu-9%WC-1%Gr hybrid composites. Similarly, Cu-6%WC-1%Gr hybrid composites exhibited a 24% and 22% increment in the UTS, and yield strength was observed as compared with the base alloy. This improved mechanical strength of the hybrid composites is associated with excellent plastic strain-sustaining capability, which is increased by the higher interfacial bonding between the materials. Furthermore, adding these reinforcements hampers the dislocation motion by repulsive or attractive interactions, which is linked to strain hardening [27]. The mechanical properties of the copper hybrid composites consist of different concentrations of reinforcement, which are presented in Table 4. From these mechanical results, it could be concluded that adding the silicon carbide and tungsten carbide along with graphite particulates into the copper matrix alloy holds promise for improved tensile properties. The improvement in the tensile properties also indicates that the reinforcement particles exhibited great wettability with the molten copper alloy. A significant increase in the strength of the materials is observed due to the transfer of tensile load from the ceramic reinforcement (SiC and WC) to the copper C87600 alloy matrix.