论文部分内容阅读
对铸态GH4169合金不同部位试样进行了不同热压缩试验,利用扫面电子显微镜、金相显微镜、EBSD研究了该合金在不同热压缩条件下的变形行为与枝晶组织的关系,并探讨了其机理。结果表明:高温热变形过程中,铸态GH4169合金的变形抗力与形变量、应变速率以及变形温度有关。变形量增大、应变速率增高、温度降低会导致变形抗力增大。当变形量为45%时,高应变速率和高温对动态再结晶更加有利。当加载方向与一次枝晶方向垂直时,材料的热变形机制为二次枝晶滑动,由此会导致应变速率敏感因子变大。初始组织为等轴枝晶的样品最有利于动态再结晶,中心粗柱状晶样品具有最大的变形抗力,而边缘细柱状晶样品再结晶比例最低、变形抗力最小。
Different hot compression tests were carried out on different parts of as-cast GH4169 alloy. The relationship between deformability and dendritic structure of the alloy under different thermal compression conditions was studied by scanning electron microscope, optical microscope and EBSD. Its mechanism The results show that the deformation resistance of as-cast GH4169 alloy is related to deformation, strain rate and deformation temperature during high temperature hot deformation. Deformation increases, the strain rate increases, the temperature decreases will lead to increased deformation resistance. When the amount of deformation is 45%, high strain rate and high temperature are more favorable for dynamic recrystallization. When the loading direction is perpendicular to the primary dendrite direction, the thermal deformation mechanism of the material is secondary dendritic sliding, which leads to the increase of the strain rate sensitivity factor. The sample with the initial structure of equiaxed dendrites is the most conducive to dynamic recrystallization. The center coarse columnar crystal sample has the largest deformation resistance, while the edge thin columnar crystal sample has the lowest recrystallization proportion and the least deformation resistance.