Investigation of deep rolling effects on the fatigue life of Al–SiC nanocomposite

Abstract

In this paper, deep rolling treatment (DRT) is performed to improve the fatigue resistance of Al–SiC nanocomposite samples. The samples are fabricated using mechanical milling, cold pressing, and hot extrusion techniques. Relative density measurement, micro-hardness and tensile tests along with microstructural examinations of the specimens are used to investigate the nanocomposite behavior. The results exhibit enhancement in micro-hardness and tensile strength and reduction in relative density as the reinforcement content increases. The main purpose of this paper is to study the effects of DRT on fatigue life of nanocomposite samples. The optimized values of DRT parameters such as the rolling depth, rotational speed, feed rate, and passes number are initially determined by measuring the surface roughness assuming that the parameters value leading to the minimum roughness may have the best effects on the fatigue behavior. Conducting DRT with its most effective parameters improved the fatigue life near 290% for non-reinforced aluminum (stress level of 230 MPa), 220% for Al-1.5 vol% SiC nanocomposite (stress level of 280 MPa), and 170% for Al-3 vol% SiC nanocomposite (stress level of 280 MPa).