Strength Determination Based on the Results of Modeling the Crack Propagation in a Nanostructured Hard Alloy

Abstract

The process of crack propagation from the initial pore in the microstructures of WC-Co alloys with different volume fraction of the cobalt phase was studied by simulation of the stressed state by the finite element method. A calculation of the energy release rate during the propagation of crack through sections which consist of the carbide grains and the cobalt phase was made. It is shown that the strain energy release rate increases with crack propagation in WC grains and decreases with crack propagation in the intermediate layers of cobalt. The maximum stresses required for the destruction of the cobalt layer determine the strength of the entire microstructure. The strength of the alloy increases when decreasing pore diameter and increasing the cobalt phase fraction.