Hardness of carbon fiber reinforced plastics (CFRP) and Al-2 and 4wt% Cu alloys containing columnar grains was measured with a wedge-shaped indenter, and was compared with their static tensile properties. Hardness measurement was conducted with a Rockwell hardness tester. The hardness and mean pressure of CFRP decreased with the angle θ between indentation normal and fiber direction. The orientation dependences of the hardness and the mean pressure agreed with those of Young's modulus and the fracture strength of CFRP. However, no linear relation existed between the mean pressure and the strength. The hardness and the mean pressure of Al-Cu alloys took a minimum when the angle θ was about π/4 rad, and the orientation dependence of the mean pressure disagreed with those of the yield stress and the ultimate tensile strength. The relation between the mean pressure and the yield stress was described by the equation: σy=(P/3)(0.0017)n, where n is the strain hardening coefficient.
