【摘要】 通过对DD100单晶合金组织、断裂等方面的研究，探讨了影响单晶的断裂延性的因素。当DD100单晶合金中加入适量Hf元素后，单晶合金中无明显的疏松孔洞，γ／γ’共晶数量增加。发生瞬间断裂的不含Hf元素的试样中存在亚晶界、疏松孔洞以及γ／γ’共晶，但亚晶界的危害超过后两者。更多还原

【Abstract】 The microstructure and fracture of Ni-based single crystal DD100 and the factors of influencing the ductility of the alloy have been investigated. With an addition of Hf in DD100 alloy,no obvious porosities were found and the amount of γ/γ’ eutectic was increased. Sub-boundaries,porosities and γ/γ’ eutectics appear in the tensile specimens without containing Hf. It was found that the effect of sub-boundary on the properties was greater than the others.更多还原