Experimental verification and numerical analysis on plastic deformation and mechanical properties of the in-situ TiB2 homogeneous composites and TiB2/Cu network composites prepared by powder metallurgy

Abstract

In this paper, three different configurations of composite materials models of TiB2/Cu homogeneous structure, single TiB2/Cu network structure and hybrid reinforced (TiB2p+TiBw)/Cu network structure are established based on their actual microstructure. The models take into account the ductile fracture of the matrix, the brittle fracture of the reinforcing phase and the traction separation behavior of the interface. Influence of mesh size and mass scaling factor on the simulation results are discussed. The validity of the simulation results is verified by the agreement of the experimental tensile stress-strain curve. The effects of TiB2 particle size, volume fraction and hybrid effects of TiB2p+TiBw on plastic deformation and mechanical properties of composites are assessed from the three aspects: interface damage, load-bearing capacity of reinforcement and matrix damage. Compared with the TiB2/Cu homogeneous composites and the single TiB2/Cu network composites, the hybrid reinforced (TiB2p+TiBw)/Cu network composites has better comprehensive mechanical properties, and its tensile strength and elongation are 349 MPa and 10.6 %, respectively. The addition of whiskers can effectively improve the bearing capacity of the hybrid reinforced (TiB2p+TiBw)/Cu network composites, but reduce the elongation of composites.