Microstructural change, stress rupture property, deformation and fracture mechanisms of Nimonic 105 superalloy at 750 °C have been studied. Experimental results showed that the stress rupture strength of the alloy at 750 °C for 10⁵ h is about 200 MPa. γ′ precipitates and M₂₃C₆ carbides grew gradually with prolonging the rupture time, while no significant change was observed in MC carbide morphology. After stress rupture test at 750 °C and 250 MPa for 23,341 h, a transition from spherical to cuboidal morphology of γ′ precipitates was found, and nearly continuous chains of M₂₃C₆ carbides formed on the grain boundary. Orowan looping and strongly coupled dislocation pairs cutting and microtwinning were the dominant deformation mechanisms at 750 °C and 350–450 MPa, while the main deformation mode was Orowan looping at 750 °C and 250 MPa. The failure of the alloy was mainly attributed to the nucleation, growth and interlinkage of voids.

研究了Nimonic 105高温合金在750°C时的显微组织变化，应力断裂特性，变形和断裂机理。实验结果表明，该合金在750°C下10 ⁵  h的应力断裂强度约为200 MPa。随着断裂时间的延长，γ'析出物和M ₂₃ C ₆碳化物逐渐生长，而MC碳化物的形态无明显变化。在750°C和250 MPa的压力下进行了23,341 h的应力断裂测试后，发现γ'沉淀物从球形转变为长方体形态，并形成了几乎连续的M ₂₃ C ₆链在晶界形成碳化物。在750°C和350-450 MPa时，Orowan环和强耦合位错对的切割和微孪晶是主要的变形机制，而主要变形模式是在750°C和250 MPa的Orowan环。合金的失效主要归因于空隙的成核，生长和互连。