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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°C for 3 h.For samples treated at 1100°C,the strength drops down due to the precipitates of Y3Al5O12(YAG).
A Y2O3 dispersion-enhanced 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 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. as-deposited sheet shows poor ductility due to micropores between columnar grains. Strength and ductility can be improved effectively by annealing at 800 ° C for 3 h.For samples treated at 1100 ° C, the strength drops down due to the precipitates of Y3Al5O12 (YAG).