【摘要】 研究了在不同熔体过热处理条件下一种镍基单晶高温合金的高温持久性能,并观察了持久断裂后的断口及变形组织。结果表明:随着熔体处理温度的提高和保温时间的加长,γ’筏型组织的完善程度增加,厚度减小;断口上韧窝数量、尺寸、形状均不同,显示出韧性断裂特征;热处理态单晶高温合金在1010℃,248 MPa下的高温持久寿命有大幅度提高、高温伸长率增加38.9%。更多还原

【Abstract】 The stress rupture characteristics of DD98 Ni-based single crystal superalloy by different melt over-heating treatments were investigated.The results show that with increasing of melt over-heating temperature and holding time,γ′ rafts become more perfect and their thicknesses are gradually decreased;stress rupture fracture reveals many dimples of different morphologies,quantity,size and shows ductile fracture mode;stress rupture life is improved gradually and elongation is enhanced about 38% under the condition of 1010 ℃,248 MPa.更多还原