On the correlation between hardness and tensile strength in particle reinforced metal matrix composites

The correlation between macrohardness and tensile strength of particle rein forced metal matrix composites was studied. Contrary to monolithic metals, a simple relationship between hardness and tensile strength was not found. The reinforcement fraction and matrix strength appear to play an important role in influencing the behavior of the composite under hardness and tensil e loading conditions. The different loading modes of the tensile test compa red to the hardness test, along with the local increase in particle concent ration directly underneath the indenter during indentation, result in a sig nificant overestimation of the tensile strength by the hardness test, espec ially when the matrix strength is relatively low. (C) 2001 Elsevier Science B.V. All rights reserved.