Effects of heat treatment on mechanical properties of ODS nickel-based superalloy sheets prepared by

• 作 者: CHEN Song QU Shoujiang LIANG Jun HAN Jiecai
• 机 构: Center for Composite Materials, Harbin Institute of Technology, Harbin 150001, China
• 出 处: 稀有金属（英文版）
• 发表日期: 2011年1期
• 关键词: superalloys nickel alloys mechanical properties heat treatment electron beams ph

A Y2O3 dispersion strengthened nickel-based superalloy sheet (0.15 mm thick) was prepared by electron beam physical vapor deposition (EB-PVD) technology. Different heat treatments were used to improve the mechanical properties of the alloy sheet. Differential thermal analysis (DTA) was used to examine the thermal stability of the as-deposited sheet. Element contents, phase composition and microstructure investigations on as-deposited and heat treated specimens were performed by X-ray fluorescence spectrometer (XRF), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Tensile tests were conducted at room temperature on specimens as-deposited and heat treated. The results show that the as-deposited sheet is composed of equiaxed grains on the substrate side and columnar grains on the evaporation side. The as-deposited sheet shows poor ductility due to micropores between columnar grains. The strength and ductility can be improved effectively by annealing at 800℃ for 3 h. For samples treated at 1100℃, the strength drops down due to the precipitates of Y3Al5O12(YAG).