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In this research, SiC/Al A413.1 functionally graded materials (FGMs) were fabricated by the vibrating centrifugal solid particle method (VCSPM), and the effects of the SiC particles on the microstructure and thermo-mechanical properties of an A413.1 aluminium alloy were investigated. The benefits of a vibration during centrifugal casting of FGMs are illustrated. After designing and fabricating the centrifugal casting machine, cylindrical FGM specimens were produced using the centrifugal solid particle method (CSPM) and VCSPM. This study used SiC particles with an average particle size from 50 to 62 μm as reinforcements to fabricate A413.1-10 wt% SiC functionally gradient composites at three annular mould speeds (900–1500 and 2100 rpm) and with or without a vibration of the mould. The Brinell hardness was measured; the yield strength (YS), ultimate tensile strength (UTS) and Young’s modulus (E) were determined by tensile testing; the density was determined by the Archimedes method; and the thermal expansion coefficients were measured with a dilatometer. A comparison of the samples produced by the conventional method and VCSPM shows a significant reduction in the porosity and an increase in the distribution gradient of the reinforcing particles for the VCSPM case. It can be concluded that in both processes, the mechanical and thermal properties improved in most cases by moving from the inner radius to the outer radius because of the movement of particles towards the outer radius from the centrifugal force. The results also show that the use of a vibration dramatically increased the rate and speed of migration of gas bubbles towards the inner radius, and the mechanical properties (hardness, YS, UTS and E) improved by moving from the inner to outer radius due to an increase in the percentage of silicon carbide particles. Upon increasing the velocity and using the VCSPM, the slope of these changes becomes steeper than those for the vibration-free mode and at low rotation speeds.

Cylindrical rotating components have been of special interest in different industries and due to their wide applications such as grinding wheel, drive shaft; the analyses of elastic and plastic stress and strains have been an interesting topic for investigation. Therefore, in this study an analytical elastic and elasto-plastic solution to evaluate the stress field in axisymmetric thick-double-walled cylindrical hollow shafts made of functionally graded materials and homogeneous layers subjected to pressure, temperature gradient, and angular speed are presented. In the first step, by considering the combined different loading condition, a closed-form analytical thermo-elastic solution for radial and circumferential stresses as well as the normalized effective stresses are presented. Then, the starting radius of the plastic deformation by using a completely elastic solution and a failure criterion is determined. In the second stage, the relations for determining the plastic zone radius as well as the radial, circumferential, and effective stresses in both elastic and plastic zones are obtained for three types of functionally graded layers under different combined loading condition. Finally, it will be shown that by using the functionally graded layer, the stress distribution and consequently the yield pattern in the thick-double-walled cylindrical hollow shaft can be improved.

In this article, an analytical solution is presented to evaluate the stress field in axisymmetric double-walled cylinder made of functionally graded materials (FGMs) and homogeneous layers ...