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 TiB 2 /Cu homogeneous structure, single TiB 2 /Cu network structure and hybrid reinforced (TiB 2p +TiB w )/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 TiB 2 particle size, volume fraction and hybrid effects of TiB 2p +TiB w on plastic deformation and mechanical properties of homogeneous and network Cu matrix composites are studied. The mechanical properties of these of composites are predicted and further assessed from the three aspects: interface damage, load-bearing capacity of reinforcement and matrix damage. Compared with the TiB 2 /Cu homogeneous composite and the single TiB 2 /Cu network composite, the hybrid reinforced (TiB 2p +TiB w )/Cu network composite has better comprehensive mechanical properties, and its tensile strength and elongation are 349MPa and 10.6%, respectively. The addition of whiskers can effectively improve the bearing capacity of the hybrid reinforced (TiB 2p +TiB w )/Cu network composite, but reduce the elongation of composites. The results provide theoretical basis and guidance for large-scale preparation of high strength and high conductivity Cu matrix network composites.

Keywords: Cu matrix composites, Plastic deformation, The hybrid effects of TiB2/TiB, Network composites, Homogeneous composites, Mechanical properties.