Tribological behaviour of semisolid–semisolid compocast Al–Si matrix composites reinforced with TiB2 coated B4C particulates

摘要: Abstract The purpose of this paper is to provide a deeper understanding the wear behavior sol–gel coated B4C particulate reinforced A356 matrix composites. A typical microstructure composite consists relatively large primary phase globules which are surrounded by particles. In fact themselves particles free and consequently sample not homogeneous on scale smaller than globule size. sliding test disclosed that rate composites less unreinforced alloy decreases with increasing volume fraction particulates. As hardness higher, reduces cutting efficiency abrasives abrasion loss. Once fracture or loosen from alloy, they can be removed easily matrix, contributing material Two kinds debris present irregular-shaped flake, has withstood plastic deformation then pull off surface. During wear, Iron transferred surface steel counterface forming iron-rich layer contact surfaces increases content substantially harder bulk largely because it contains fine mixture Fe phase, Al B4C.