Mechanical Properties, Mechanism of Damage and Failure of Nano-structured Graded Composite of TiB2-based Ceramic and 42CrMo Alloy Steel

Abstract:

By taking centrifugal reactive casting processing to prepare the TiB2/42CrMo laminated composites, flexural strength, fracture toughness and interlaminar shear strength of the laminated composite measured 1250 ± 35 MPa, 75 ± 12 MPa·m1/2 and 450 ± 20 MPa respectively. Because the microstructure with the nano-structured gradient directly developed in the ceramic/steel interlaminar region, the ceramic/alloy phase-boundary size with continuous gradient was spatially formed from the ceramic to the steel. As a result, the laminated composite not only had the plastic deformation capacity similar to the metal, but more importantly also exhibited strong mechanical behaviors of failure delay in both load-displacement curves during 3-point bending test and short-beam interlaminar-shearing test.

Key words:laminated composite; interlaminar interface with nano-structured gradient; mechanical behaviors; failure delay