GH4710合金的相析出特征及其与热加工塑性损伤的关联性

利用Thermal Calc热力学软件、光学金相显微镜、扫描电镜等手段分析了GH4710合金原始态和不同条件热物理模拟变形后的析出相及加工损伤特征，系统研究了析出相特征与该合金热加工塑性损伤及开裂的关联性.结果表明：GH4710合金的原始组织主要由γ'、MC及M₂₃C₆碳化物、γ+γ共晶组织组成；热加工时微孑洞等损伤在MC碳化物及γ+γ共晶组织处形核后沿晶界扩展，最终相互连接导致合金大面积破坏；γ'相优先在MC碳化物及共晶组织附近析出，并通过其共格应力场的作用增加了损伤形核和扩展阻力，使合金在较低温度下的塑性损伤值明显小于高温条件下.

Precipitation characteristics of GH4710 alloy and its relationship to plastic damage evolution during hot working process

The characteristics of precipitates and plastic damage in GH4710 alloy, both under original and different hot-forming conditions, were studied based on thermomechanical calculation by the Thermal Calc software and microstructural analysis by optical microscopy and scanning electron microscopy. The relationship between the precipitation characteristic and plastic damage evolution during the hot-forming process was also discussed. It is found that the equilibrium phases of the alloy mainly consist of γ', MC and M₂₃C₆ carbides, and γ/γ' eutectic structure. The MC carbides and eutectic structure act as damage sources during the deforming process, leading to the nucleation and connection of micropores, and then the propagation of macrocracks through the grain boundaries. The γ' phase precipitates preferentially at the MC and eutectic structure region of as-solidified structure, which impedes the nucleation and expanding of micropores by the γ/γ' coherent stress distribution, resulting in a lower plastic damage at sub-solvus deformation temperatures and a higher plastic damage at super-solvus deformation temperatures.