Thermal Properties of a Cobalt-based Superalloy Designed to be Reinforced by Titanium Carbides and Chromium Carbides
Propriétés thermiques d'un superalliage base cobalt conçu pour bénéficier d'un renforcement par carbures de titane et carbures de chrome
Abstract
In this study titanium carbides were considered to strengthen alloys elaborated by classical foundry and displaying a polycrystalline structure. A model alloy, whose composition is Co(bal.)-25Cr-0.5C-1Ti (wt.%), serves as a kind of prototype to test the possibility of formation of TiC carbides during solidification and the thermal resistance of these particles at elevated temperature. This alloy was synthesized by high frequency induction melting under inert atmosphere and was subjected to microstructure characterization, Differential Thermal Analysis and exposure at 1100°C for about two days. A dendritic cobalt-based matrix was obtained with, in the interdendritic spaces, chromium carbides and titanium carbides. The melting point measured by DTA is slightly below 1300°C and the titanium carbides well resisted to the exposure at high temperature. Ongoing tests carried out to assess the mechanical behavior at high temperature suggest rather high potential of creep resistance at 1100°C.
Origin : Publication funded by an institution
Loading...