Manufacturing Process of Carbon Short Fiber Reinforced Al Matrix With Preformless and Their Properties

Abstract

Conventional manufacturing process of fiber reinforced metal matrix composites via liquid infiltration processes, preform manufacturing using inorganic binders is essential. However, the procedure involves binder sintering, which requires high energy and long operating times. A new fabrication process without preform manufacturing is proposed to fabricate carbon short fiber (CSF)-reinforced aluminum matrix composites using a low-pressure infiltration method. To improve the wettability and avoid interfacial reactions in CSF/Al matrix composites, the fibers were plated with copper using electroless plating process. Various volume fractions of CSFs were used to determine optimum fiber content which would produce versatile mechanical and thermal properties. Effect of CSFs content on properties such as Vickers hardness and thermal conductivity was studied. Cu-plated CSFs showed good bonding with the Al matrix and CSFs were randomly dispersed inside the composites, with CSF content of up to 29.1 vol.%, through the new manufacturing process. It showed better fiber distribution than the composite fabricated perform with SiO2 binder, which was determined by comparing the relative frequency distribution of CSFs in composites. Vickers hardness of the composites showed an obvious improvement over that of the Al matrix, and the hardness increased as the CSF content increased. The Cu-plated CSF (14.3 vol.%) reinforced Al matrix composite exhibited the highest thermal conductivity (184.1 W·m-1·K-1). However, the thermal conductivity decreased as CSF content increased to 29.1 vol.% due to the defects in composite.