The Fracture Toughness of Some Metal Matrix Composites - Comparison of Techniques

Abstract

The ability to measure plane strain fracture toughness on small specimens, such as biomaterials and developmental alloys, and on materials that do not lend themselves to fatigue pre-cracking is becoming increasingly important, especially with the profusion of "advanced" materials now being developed. The short rod and short bar chevron notched specimens address this. This paper looks at the correlation between valid KIc data and short rod fracture toughness (both KIv and KIvm)for a series of metal matrix composites. It is shown that the relationship between these values form part of a family of curves that exist for monolithic alloys. The relationship appears to be independent of the use of maximum or critical load values in the calculation of short rod fracture toughness.