Wear behavior and wear mechanism of iron foam reinforced SiCp/A359 interpenetrating phases composites at high temperature

The A359-SiCp/Fe interpenetrating phase composites reinforced with three-dimensional network structure iron foam and 20 wt. % SiC particles were fabricated after the infiltration technique by using the newly developed vacuum assisted infiltration procedures. The dry-sliding tribological behavior of A359-SiCp/Fe composites was investigated using the HT-1000 ball-on-disc type high temperature tribometer. The samples were subjected to a variety of temperatures and applied loads to investigate the influence on the wear rate and friction coefficient. In this study, SEM was used to analyses the wear microscopic morphology of A359-SiCp/Fe composites reinforced by iron foam. The wear longitudinal section and the morphology of the wear debris were analyzed by EDS and determined to explore the high-temperature wear mechanism under different temperatures and loads. Hardness analysis from the outer periphery to the core revealed an improvement in hardness. The hardness distribution of the wear longitudinal section is different at different temperatures. The formation of a high-hardness mechanical mixed layer with a different thickness on the wear surface can effectively reduce the wear rate. Microstructural investigations demonstrated that the change in wear debris shape with increasing temperature is mostly related to the change in wear mechanism. Abrasive wear and oxidation wear are the main wear mechanisms. With an increase in temperature and plastic deformation, delamination and adhesion are the predominant wear mechanisms, accompanied by the additional oxidative wear.