الفهرس 
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Abstract
The present work investigates the correlation between the microstructural and mechanical changes in the Al-Ni/SiC composites processed by accumulative roll bonding (ARB) technique. Three different SiC concentrations, 1, 3, and 5% were considered to reinforce Al and Al-Ni dual-matrix composites. ARB process was applied up to 7 cycles to manufacture a composite with homogenous dispersion of the three phases. The microstructure, phase analysis, electrical and thermal properties, tensile and hardness properties have been investigated for the ARBed sheets and their composites. Also, the fracture surface of the tensile-tested specimens was studied using SEM analysis. The response surface methodology was applied to study the interaction effect between the selected accumulative roll bonding (ARB) parameters on the tensile strength and the hardness of the ARBed composite sheets. And numerical equations have been generated to predict the properties of the composite sheets. Also, numerical optimization is conducted to detect the optimum parameters of the ARB process in the designed experimentations. The results showed that the presence of Ni layer between Al and SiC particles enhanced the dispersion of SiC in the matrix, which positively affects the mechanical strength. The maximum tensile achieved was 257 MPa for composite containing 3 wt.% SiC after 7 ARB cycles compared to 37.2 MPa for the AA1050. The hardness values of the ARBed AA1050, AA1050-Ni, and AA1050-Ni/5 Wt.% SiC are 85.5, 93.5, and 109.7, respectively, after 7 ARB cycles. The modeling analysis results confirm the significance of the applied ARB parameters in the properties of the ARBed sheet composites. The numerical optimization analysis indicates the optimum ARB factors are 7 cycles and 3.2 wt.% of SiC content to produce an AA1050/Ni-SiC composite sheet with 249.2 MPa tensile strength and 107.8 HV hardness.