A statistics based numerical investigation on the prediction of elasto-plastic behavior of WC-Co hard metal

This paper focuses on the evaluation of the nonlinear elasto-plastic behavior of a WC-Co composite by a computational micromechanics approach. Due to the non-periodic nature of the material, the difficulty underlies primarily in determining a representative volume element (RVE) which is efficient in embodying the microstructure of the material and the global material feature predicted from it would not been strongly distorted. For this purpose a statistics based methodology is proposed as well as a model generation technique which is capable to convert real images taken from scanning electron microscopy (SEM) automatically into a finite element model. Based on this technique, a series of SEM images were studied with the emphasis to investigate the impact of the RVE size on the prediction of the composite behavior in a statistical manner. Furthermore, the paper discusses the impact coming from additional factors, such as boundary conditions and element type. Simulation results based on various case studies are compared with experimental observations and a statistical perspective in RVE size determination is introduced.