High temperature tensile damage behavior of ZrB₂-based composite: Experimental investigation and modeling

The uniaxial tensile behaviors of ZrB₂-SiC-graphite composites at the room temperature of 1400 °C, 1600 °C and 1800 °C, were investigated respectively, in which the tensile direction is parallel to the basic plane of the graphite. The tensile deformation and damage behavior were discussed through high temperature tensile experiments and the prediction model. Results showed that ZrB₂-SiC-graphite composites displayed an evident nonlinear tensile behavior with the increase of temperature. Tensile deformation increased with the increase of temperature, and the maximum deformation at 1800 °C was almost seven times than the value at the room temperature. Furthermore, a damaged high temperature constitutive model was applied to describe the nonlinear condition, and to predict tensile stress-strain relationship and tensile deformation and strain. Numerical tensile deformation was in good accordance with the experimental result, which illustrated the applicability of this model for tensile behavior in the condition of high temperature. Additionally, numerical results showed that the value and range of mechanical damage increased with the increase of temperatures, and a rapid increase above the brittle-ductile transition temperature.