2015 Volume 56 Issue 648 Pages 34-39
In order to gain the fundamental knowledge of plastic deformability in a Cr-Cu composite material containing a high fraction of Cr particles, tensile tests of 50mass%Cr-Cu composites were performed at 299K to 473K. Although single-phase Cr generally shows brittle fracture at temperatures lower than approximately 350K, the Cr-Cu composite shows ductile fracture at all tested temperatures. The tensile strength and fracture elongation decreased with increasing testing temperature. These tensile properties of the high-Cr-fraction Cr-Cu composite originate from the properties of a matrix material comprising a Cu alloy with a small amount of dissolved and precipitated Cr. However, the reduction in area was increased with increasing testing temperature. The deformation characteristics of the Cr-Cu composites were considered in terms of the re-arrangement, elongation, and rotation of Cr particles in a ductile Cu matrix. In addition, the ductile-brittle transition behavior of Cr particles would affect the tensile property of Cr-Cu composite at 353K to 373K, which is the range of the ductile-brittle transition temperature (DBTT).
