Correlation between pore structure and compression behavior of porous sintered Cu-Ni-Cr alloy at elevated temperatures

The correlation between pore structure and compression behavior in porous Cu alloy was examined at elevated temperature. The model alloy system consists of a porous Cu-Ni-Cr alloy matrix with 51%-62% porosity. Scanning electron microscopy and numerical simulation were used to examine and to analyze the details of the microstructure and deformation surface. Compression tests were utilized to evaluate the mechanical properties from 550 to 650 degrees C. The compression strength, elastic modulus, yield stress all increased with a decrease in porosity. Two-dimensional microstructure-based finite element modeling showed that the pore size and pore structure were the main effects on the compression properties of porous Cu alloys. The enhanced compression behavior of the denser alloys could be attributed to smaller pore size and porosity which resulted in more homogeneous deformation and decreased strain localization in the material. Otherwise, the shape of pore has a severe influence on the structure stability properties of the material, i.e. every increase of pore edge corresponds to a decrease of stability in structure.