In this study, Al/SiC/Gr hybrid composite was fabricated by continual annealing and roll bonding (CAR) process up to eight cycles.For this purpose powder particles with 2 wt.% which include pure SiC and SiC/Gr powder mixture with different weight percent 95SiC/5Gr and 80SiC/20Gr were selected. Microstructure, mechanical and wear properties were evaluated. Before CAR process, the composite strips produced by cold roll bonding (CRB) in the same conditions as CAR processing, and to evaluate the bond strength between layers and the effective farctors on it, peeling test was applied. The peeled of surfaces after peeling test were investigated by scanning electron microscope (SEM). The results showed that the bond strength increases with increasing the reduction in thickness, post rolling annealing and decreasing Gr content. By increasing the number of CAR cycles, the particles were distributed more uniformly in the matrix and the amount of pores were decreased. The tensile strength of composites increases with increasing the number of CAR cycles and percent of elongation decreased up to four cycle and then increased. After the eight cycle, the hybrid composite exhibited the tensile strength of about 122 MPa and the percent elongation of about 43%. Wear test results showed that the wear resistance of CAR processed samples is higher than that of annealed sample and the wear resistance increased with increasing of cycles. The highest wear resistance was observed in Al/SiC-Gr hybrid composite with 4×10-6 (g/N.m) in wear coefficent and 0.3 in coefficent of friction.

In this study, Al/SiC/Gr composite was fabricated by accumulative roll bonding (ARB) up to eight cycles. The powders were used with different compositions (in wt.%): 100SiC, 95SiC-5Gr, 80SiC-20Gr and 20SiC-80Gr. In all composites, the total amount of particles was considered to be about 2 wt.%. Microstructure, mechanical and wear properties was evaluated. Results showed that after four cycles, the microstructure of the Al/SiC composite was inhomogeneous. In contrast, a homogeneous ultra-fine grain structure with the average grain size of about 710 nm was formed after eight ARB cycles. By increasing the number of ARB cycles, the particles were distributed more uniformly in the matrix and the amount of pores were decreased. The bonding quality between the layers was reduced and the mechanical properties of the composite deteriorated considerably with increasing the Gr content. The Al/SiC-Gr(95:5) composite exhibited the highest tensile strength (about 213 MPa) while the lowest tensile strength was obtained for the Al/SiC-Gr (20:80) composite (about 145 MPa). Tensile fracture surfaces of the hybrid composites showed that Gr particles caused several delaminations between the layer interfaces. Wear test results showed that the wear resistance of ARB processed sample is higher than that of annealed Al. The Al/SiC-Gr(80:20) composite exhibited the lowest wear rate 4×10-6 (g/N.m) and lowest coefficent of friction (0.4). Wear rate of the composite increased by increased up to addition of 80%wt Gr.

In recent years, accumulative roll bonding (ARB) process is taken into consideration as a novel method for producing metal matrix composites (MMCs). Accumulative roll bonding (ARB) was used to fabricate Al/Ni (with two initial Ni thicknesses) and Al/Ni/Fe3O4 composites. Microstructural observations showed that in all composites, Ni layers necked and fractured during ARB owing to the difference in flow properties of Al and Ni. In addition, in the Al/Ni/Fe3O4 composite, large and elongated clusters of Fe3O4 particles were broken into smaller ones and distributed gradually in Al matrix. After the fourth and sixth cycles, weak bonding and several porosities were observed at particle/matrix interface while the bonding quality increased after the eighth cycle. Results showed that after eight cycles, an Al-based composite with a satisfactory magnetic behavior was produced. The Al/Ni(0.5) composite exhibited the highest tensile strength (182 MPa) with the highest value of saturation magnetization (13.47emu/g). Hardness of aluminum matrix and reinforced fragments of nickel increased with increasing the ARB cycle. Fracture surfaces of all samples revealed dimples that are the characteristic of the typical ductile fracture. The relative permeability decreased with increasing frequency for a given number of ARB cycles. Fe3O4 particles caused the saturation magnetization to decrease and the critical frequency to increase due to the eddy current effects.

 In this study, Al-Cu-Ni and Al-Cu-Ni/SiC composites were fabricated using accumulative roll bonding (ARB) and electroplating processes. Ni layer with thickness of about 10 µm and Ni/SiC composite layer with different thicknesses of about 25, 50 and 150 µm were generated by electroplating on the copper substrate. The microstructure evolution and tensile behavior of the composites were studied by optical/scanning electron microscopes and tensile test. In the Al-Cu-Ni composite, first the Ni layers and then the copper layers were necked, fractured and distributed uniformly in the Al matrix. In the Al-Cu-25Ni/SiC composite, a completely uniform distribution of reinforcements with good bonding at the matrix-reinforcement interface were achieved. After eight cycles, cavities, debonding and a nonhomogeneos distribution of the reinforcements were observed in the Al-Cu-50Ni/SiC and Al-Cu-150Ni/SiC composites. The Al-Cu-25Ni/SiC composite exhibited the highest tensile strength of about 310 MPa in comparison to the others. The lowest tensile strength was achieved in the Al-Cu-150Ni/SiC composite due to the formation of the cavities and debonding at the interfaces. Fracture surfaces of all samples revealed dimples that are the characteristic of the typical ductile fracture.

: In the present study, an Al-Al2O3 composite was produced by accumulative rolls bonding (ARB) through two processing routes. In the first route, a combination of ARB and plasma electrolytic oxidation (PEO) was utilized. In the second route, a particulate Al-Al2O3 composite was fabricated by using ARB and dispersing 4 vol.% Al2O3 particles with two different sizes (1 𝝁m and 0.5 𝝁m) between the Al strips. Results showed that after imposing a sufficient ARB cycles, a uniform distribution of Al2O3 fragments (in the former) and particles (in the later) were observed in the Al matrix. The tensile strength of Al-Al2O3 composite produced by the first route reached to about 180 MPa, four times higher than of the annealed Al (47 MPa). The particulate Al-Al2O3 composite exhibited the tensile strength of about 170 MPa and 175 MPa for 1 𝝁m and 0.5 𝝁m Al2O3 particles, respectively. In comparison to the annealed Al, the uniform elongation of the composites fabricated by each processing route decreased remarkably. The fracture surface of the composites reveals several dimples, which are the characteristics of a typical ductile fracture

AnAl- 2Vol.%Al2O3/SiChybrid metal matrix composite was fabricated with two kind of aluminum (Al1200 and Al1050) by accumulative roll bonding (ARB). For comparison, non-reinforced (monolithic) Al was also processed by ARB. At initial stages, particle free zones as well as particle clusters were observed on the microstructure of the composites. After eight ( for Al1050 samples) and six (for Al1200 samples) ARB cycles , a composite with the uniform distribution of particles was achieved. At this stage, the tensile strength and hardness of the Al1050 composite reached to 194MPa and83.4VHN about 5 and 4times larger than that of the annealed Al. The tensile strength and hardness of theAl1200 composite reached to 166MPa and 76.5VHN about 4 and 3 times larger than that of the annealed Al . Fracture surface of Al1050 composite after tensile testing revealed dimples at some regions after eight ARB cycles.