Improvement of Tensile Property of Ni-Based a Single Crystal Superalloy by Ru Addition

Abstract

Two experimental single crystal superalloys, the Ru-free alloy and the Ru-containing alloy with [001] orientation, were prepared in a directionally solidified furnace, while other alloying element contents were kept unchanged. The effects of Ru on the microstructure and tensile property at 25°C, 760°C, 980°C and 1100°C of the single crystal superalloy were investigated. The results show that the size of γ′ particles became uniform, and the cubic shape of the particles turned a little regular after Ru addition. The yield and ultimate tensile strengths of the single crystal superalloy increased with variant degree at different temperatures. The fracture elongation and area deduction decreased at the testing temperatures of 25°C and 760°C, but those increased at 980°C and 1100°C. The tensile fracture mechanism of the single crystal superalloy at different temperature did not change. Finally the relationship between the improvement of tensile strength and Ru addition was discussed.