Workability studies on sintered Cu-10SiC preforms during cold axial upsetting

摘要

An investigation has been carried out for the determination of the workability behavior of Cu-10SiC composite under triaxial stress state condition. Cylindrical preforms with three different initial preform densities (namely 85%, 90% and 95% of the theoretical density), possessing aspect ratios of 0.60, 0.50 and 0.40 were prepared using a die and punch assembly with a 1.0 MN capacity Universal Testing Machine (UTM). Then the preforms were sintered in a muffle furnace at a temperature of 850 ± 10℃ for a period of 1 h. Based on the experimental results the phenomena like axial strain (ε_2), various stress ratio parameters, namely (σ_θ/σ_(eff) and (σ_m/σ_(eff), the formability stress index (β_0) under triaxial stress state conditions were systematically analysed. It was found that lower initial aspect ratio with higher initial relative density preforms exhibited enhanced formability stress index compared to higher aspect ratio with lower initial relative density preforms.