Abstract

The microstructures and properties of TiC dispersed nickel-base alloy were studied in this work. The alloy prepared by powder metallurgical processing was solution treated, 1st-aged at 880°C for 16 hours, and then 2nd-aged at 760°C for 4 hours. Microstucture of sintered specimen showed that TiC particles are uniformly dispersed in Ni base alloy. In the specimen aged at 880°C for 8 hours, the fine gammaNi_3(Al,Ti) precipitates with round shape are observed and the very fine gammaNi_3(Al,Ti) particles with round shape are precipitated in the specimen aged at 760°C for 4 hours. The presence of gammaprecipitates in TiC/Ni base alloy increased the hardness and wear resistance of the specimen. The hardness and wear resistance of the Ni-base with TiC are higher than those of conventional Ni-base superalloy X-750 because of dispersion strengthening of TiC particles. The hardness, transverse rupture strength and resistance of the specimen 2nd-aged at 760°C for 4 hours are higher than those of 1st-aged specimen due to ultrafine gammaNi_3(Al,Ti) precipitates.

• Keywords: TiC;superalloy;Composite;Heat-treatment;Mechanical property;Aging;