中文摘要：

研究了Waspaloy高温合金在扩大锭型后，铸锭中元素偏析程度和均匀化处理过程中元素偏析规律并建立理论模型。采用光学显微镜、扫描电镜、能谱仪分析了该合金铸态和均匀化态的显微组织和元素的偏析规律，以此为基础分析并建立了偏析指数与材料工艺参数的关系，为扩大锭型后均匀化制度的合理制订提供理论依据。同时认为φ508mm铸锭的均匀化应分为2个阶段进行，第1阶段为1120℃的低熔点组织溶解，第2阶段为1180℃左右进行Ti，Cr元素的扩散，改善偏析。结果表明：合金在1180℃退火20h较合理。

英文摘要：

The Microstructure, elements distributions and phase distributions of Waspaloy alloy in the big size ingot before and after homogenizing treatment were investigated by optical microscope, scanning electron microscopy and EDAX. The theoretical model was established. Based on this model, the relationship between segregation index δ and several process parameters was discussed. The result showed that the homogenizing process of Waspaloy included two stages： the first stage to resolve low-melting structure at 1120℃ .and the second stage to eliminate elements segregation at 1180℃. The experimental and calculated result proved that the annealing at 1180℃ for 20 h was reasonable.