CAJ | 학술논문

对GH4698合金在室温、650及750℃的裂纹扩展行为进行研究，讨论温度对裂纹扩展寿命与速率的影响，观察不同温度下的裂纹扩展断口。采用背散射电子衍射(EBSD)技术对合金裂纹扩展的晶体学机制进行分析。结果表明，随着温度的升高，合金的裂纹扩展寿命降低，裂纹扩展速率增加，断裂模式由室温下穿晶断裂为主转变为高温下的沿晶断裂为主；裂纹附近应变程度较大，且小角度晶界密度较高。
대GH4698합금재실온、650급750℃적렬문확전행위진행연구，토론온도대렬문확전수명여속솔적영향，관찰불동온도하적렬문확전단구。채용배산사전자연사(EBSD)기술대합금렬문확전적정체학궤제진행분석。결과표명，수착온도적승고，합금적렬문확전수명강저，렬문확전속솔증가，단렬모식유실온하천정단렬위주전변위고온하적연정단렬위주；렬문부근응변정도교대，차소각도정계밀도교고。
The crack propagation behavior of GH4698 alloy was studied respectively at room temperature, 650 and 750℃. The effects of temperature on the crack propagation rate were discussed, the fractures under different temperatures were observed and the electron back scattering diffraction (EBSD) technique was applied to investigate the mechanism of crack propagation. The results show that with the increase of temperature, the fatigue life of the alloy reduces and crack propagation rate increases, and the main propagation mode of cracks changes from transgranular to intergranular. The grains near cracks have relative high deformation degree and high density, small angle grain boundaries.