Improvement of Creep Strength of a Third Generation, Single-Crystal Ni-Base Superalloy by Solution Heat Treatment

The standard solution heat treatment of the third generation, single-crystal Ni-base superalloy, CMSX-10, requires multiple steps at temperatures up to 1365 °C and lasts a total of approximately 45 hours. These high temperatures and long hours result in a heat treatment that is costly. Reducing the temperature and/or time of the heat treatment to reduce the cost of the heat treatment would result in residual segregation of W and Re to the dendrite cores, a locally unstable microstructure. Therefore, a modified heat treatment was evaluated that increased the maximum heat-treatment temperature and the amount of time at the higher heat-treatment temperatures. The microstructures and mechanical properties were evaluated for samples given both the standard and the modified solution heat treatment.