高温合金构件局部结构电弧增材-超声微铸锻复合成形工艺与机理研究

The aero-engine and gas turbine industries usually represents the level of national industry, technology, and comprehensive national power. The complex thin-walled ring-shaped superalloy components, such as turbine casing, have been manufactured by the ring-rolling process. However, due to the numerous annular reinforcing ribs, bosses and other structural features on the outer surface of the casing, the machining allowance is relatively large, and it is hardly to control the residual deformation after machining. Meanwhile, the material utilization and pass rate are low, and manufacturing costs are relatively high. This study combines ultrasonic micro-casting-forging process (UMCFP) with wire arc additive manufacturing (WAAM), and focuses on the hot forming of local casing structure of GH4169 superalloy. The main aim is to reveal the hot forming mechanisms of the local structure, and clarify the interactions and interface bonding mechanisms between component matrix and local structure. Moreover, the geometric precision controlling method for the forming process is explored in this study. Based on the above study, the numerical simulation model and control software system are established for the whole WAAM-UMCFP process. So, this study can promote the precise control of shape and performance for the complex thin-walled ring-shaped superalloy components. It can provide an important theoretical basis and technical support for the development of complex thin-walled ring-shaped superalloy components.

航空发动机和燃气轮机（两机）产业是衡量国家工业科技水平和综合国力的重要标志。以机匣为代表的复杂环形薄壁高温合金构件由于存在大量环形加强筋、凸台等结构特征，采用传统塑性加工工艺必须保证局部特征结构充足的机加工余量，难以大幅降低成形件厚度，整体残余变形不易控制，材料利用率和成品率较低。本项目拟将超声微铸锻工艺与电弧增材制造方法相结合，在接近目标件壁厚的机匣毛坯上，复合成形局部特征结构，进而揭示复杂环形薄壁高温合金构件局部结构的成形成性机理，阐明构件基体与局部结构的交互影响作用及界面接合机理，探明构件复合成形工艺的几何形状精度控制方法，集成建立电弧增材-超声微铸锻复合成形工艺全流程的数值仿真模型和综合控制系统软件平台，统筹实现复杂环形薄壁构件局部结构组织性能的精确调控及其与整体构件的形性协同控制。本项目的顺利开展有望为我国两机用复杂环形薄壁高温合金构件的研制提供重要的理论依据和技术支持。

航空发动机和燃气轮机（两机）产业是衡量国家工业科技水平和综合国力的重要标志。以机匣为代表的复杂环形薄壁高温合金构件由于存在大量环形加强筋、凸台等结构特征，采用传统塑性加工工艺必须保证局部特征结构充足的机加工余量，难以大幅降低成形件厚度，整体残余变形不易控制，材料利用率和成品率较低。本项目将超声微铸锻工艺与电弧增材制造方法相结合，开展了复杂环形薄壁构件局部结构组织性能的精确调控及其与整体构件的形性协同控制的研究工作，取得如下重要研究进展：①自主设计并搭建完成了电弧增材-超声微铸锻复合成形工艺制造平台，为项目的顺利开展奠定了装备基础；②通过开展扫描电镜、X射线衍射等微观表征实验，分析揭示了电弧增材-超声微铸锻复合工艺过程GH4169合金和GH4169D合金的微观组织演变规律，阐明了复合成形工艺及热处理工艺对材料组织的影响机理，提出了通过预析出δ相控制晶粒长大并消除Laves相的电弧增材GH4169合金新型热处理方法；③通过开展拉伸、显微硬度等力学性能实验，分析揭示了电弧增材-超声微铸锻复合工艺过程GH4169D合金的力学性能演变规律，阐明了复合成形工艺及热处理工艺对力学性能的影响机理；④建立了GH4169合金熔道尺寸模型，开发了基于曲面的随形分层算法和复杂形状路径的识别与拟合算法，集成建立了电弧增材-超声微铸锻复合工艺规划及设计系统；⑤建立了数值模拟与神经元网络算法相结合的电弧增材过程温度场-组织场-性能的集成预测方法与软件平台。本项目的开展对我国两机用复杂环形薄壁高温合金构件的研制具有重要的理论和技术价值。