Affiliation:
1. School of Mechanical Engineering, Guizhou University of Engineering Science, Bijie, China
2. Institute of Materials Science and Engineering, School of Mechanical and Electronic Control Engineering, Beijing Jiaotong University, Beijing, China
Abstract
TiCx-Cu cermets with various ceramic structures were prepared by infiltrating method. In this study, the effects of grain size and porosity of the preforms on the microstructures and mechanical properties of the cermets were investigated. Meanwhile, the interface between Cu and TiCx was studied. In the process of infiltration, TiC0.5 grains were eroded by the metal phases due to the reactive wetting behavior, resulting in the scattered structure of ceramics in the cermets. Compared to cermets reinforced by scattered TiC, fracture forms of TiCx-Cu cermets with the co-continuous structure included cleavage fracture of ceramic grain, ductile fracture of metal, phase interface separation between metal and ceramic, and metal root pulling out in ceramic grains. The co-continuous TiCx-Cu cermets could reduce the damage of cracks and improve the fracture toughness of the cermets through crack deflection, crack bifurcation, metal bridging, and metal pinning. In this study, cermets with 72 vol% content of TiC reached a flexural strength and fracture toughness of 914 ± 102 MPa and 11.3 ± 0.3 MPam1/2, respectively. The excellent mechanical properties are attributed to the firm interface strength and the unique structure.
Funder
Guizhou science and technology support plan project
Guizhou Provincial Education Department Supporting Program
Natural science research project of Guizhou Provincial Department of Education
Key Discipline Project of mechanical engineering of Guizhou University of Engineering Science