Erosion of fiber reinforced Ai-4 pet CU composites

Abstract

Erosion tests were carried out on a series of Al-4 pct Cu metal matrix composites containing up to 30 vol pct alumina fibers. The erosion rates were found to increase significantly with increasing fiber content. Analysis of the shift of low-angle impact erosion rate data suggests that increasing fiber content imposes ductility constraints for the deformation mechanisms operative during the erosion and impact process. SEM observations on eroded surfaces support this view. Tensile tests on the same materials also showed strong ductility constraints as a result of fiber additions. The erosion rates could be correlated inversely with the parameter σm ef obtained from tensile tests where σem is the maximum stress in the sample before failure and ef is strain to fracture. Hardness alone was not a suitable parameter for correlation because erosion rates increased with increasing hardness, contrary to what is expected based on existing theories that use hardness as the single materials parameter to model erosion.