Microscopic evaluation of elastoplastic deformation behavior of sintered tungsten alloys

Abstract

For the purpose of investigating the macroscopic and microscopic elastoplastic deformation behavior of two-phase composites: W-Ni-Fe alloys, the constitutive relations of W-Ni-Fe alloy and its microconstituents were measured by the Hopkinson pressure bar testing and usual compression testing, and then the elastoplastic deformation behavior of W-Ni-Fe alloys in uniaxial compression was analyzed using the micromechanics-based analysis method. The main conclusions are summarized as follows; (1) The work hardening tendency of W-Ni-Fe alloy is in keeping with that of pure tungsten particle phase which is B. C. C. metal. (2) Measured flow stresses of W-Ni-Fe alloy under high strain rate loading are smaller than analyzed ones, due to local failure in the matrix phase of W-Ni-Fe alloy. (3) The compressive residual stresses in the particle phase are produced at the cooling stage in sintering. (4) The micromechanics-based analysis method can precisely analyze the elastoplastic deformation behavior of two-phase composites until large deformation.