TENSILE PROPERTY AND CRACK PROPAGATION BEHAVIOR OF TUNGSTEN ALLOYS

In situ SEM experimental system is employed to investigate the mechanical characteristics and the fracture behavior of 91W–6.3Ni–2.7Fe tungsten alloys. The crack initiation and propagation of tungsten alloys under tensile loadings are examined. Multi-particle unit cell models containing the microstructure characteristics of tungsten alloys are established. Fixed-point iteration method is firstly used for the multi-particle unit cell's boundary condition. By adopting the method, real displacement constrained conditions are applied on the multi-particle unit cell models. The mechanical and fracture behaviors of tungsten alloys under tensile loading are simulated. The effects of tungsten content, particle shape, particle size, and interface strength on the mechanical properties of tungsten alloys are analyzed. The relationship between the mechanical behaviors and the microstructure parameters is studied. A good agreement is obtained between the experimental results and the numerical predictions, verifying the rationality of the FE models using the fixed-point iteration method.