1、 i 摘 要 目前，我国传统的飞机进气风罩 大多 是用铝合金钣金件分块组合焊接而成，工序繁琐，生产周期长，而且其焊接质量难以保证，在飞机飞行过程中其焊接部位经常被吹裂。为了提高飞机进气风罩的使用寿命，降低生产难度，解决生产中因分块组合焊接而带来的质量 隐患，本文采用高强度铝合金 ZL101A 和石膏型熔模精密铸造的工艺来成型进气风罩，并采用 ProCAST 铸造模拟软件对飞机进气风罩的充型凝固过程进行了数值模拟。 铸造过程的计算机模拟是近几十年迅速发展起来的现代铸造工艺研究方法， 这种方法通过对铸件进行计算机试浇及工艺分析 ， 能 较快的发现决定铸件质量的内部因素 ， 对可能出现的各种铸造缺陷
2、提出预报，从而 在工艺实施前优化所采用的铸造工艺参数，这对于指导铸造工艺设计、提高铸件质量具有重要意义。所以，为了实现飞机进气风罩的铸造生产方式 ，本论文对其 铸造 过程中 的 充型凝固过程进行了数值模拟。 首 先， 本文 对新型飞机进气风罩的石膏型熔模精密铸造工艺进行了简单的分析。 在此基础 之 上 ，建立基于 Pro/E的进气风罩 三维 几何造型。最后利用 ProCAST铸造模拟软件对进气风罩的整个充型凝固过程进行数值模拟，以精确显示 其 充型凝固过程中的充填不足、冷隔、裹气和热节的 位置以及残余应力和变形。 在此次模拟所设置的工艺参数下，铸件填充率 可 达到 98%， 这 主要是由于 铸
3、件在凝固时收缩使浇口处产生塌陷 ，所以在实际浇注过程中要注意 及时 补缩。 其他缺陷 的数量以及分布也基本符合 铸件最终的使用要求，因此，这种新型飞机进气风罩的成形工艺可以 应用于工业生产。 通过对 模拟的缺陷 的 分析， 还 可以对进气风罩的 铸造工艺过程进行优化， 从而在 实际生产前 就 采取有效的工艺措施 减少或 避免缺陷的产生。 这种方法对企业的实际生产具有一定的意义。 关键词：进气风罩； 石膏型 熔模精密铸造；凝固温度场；充型流场；数值模拟 ii Abstract At present, most of the traditional air intake hoods are wel
4、ded by the aluminum alloy sheet. Its working procedure is complicated and the production cycle is long. Moreover, the quality of welding is difficult to guarantee. So, during the flight, the welding parts are often blown crack. In order to improve the life of the air intake hood, to lower the produc
5、tion difficulty and to solve the quality risks in the production due to the method of weld, in this article, the high-strength aluminum alloy ZL101A and plaster mould investment casting were used to mold the intake hood, and the filling and solidification process of the air intake hood was simulated
6、 by the casting simulation software ProCAST. Computer simulation of casting process is the modern casting study method which developed rapidly in recent decades. The internal factors which determine the quality of the casting can be found quickly by pouring and analyzing the working process by compu
7、ter. To different kinds of possibly casting defects, the prediction is brought up. Thereby, the process parameters of the casting are optimized before the implementation of the process. It is of great significance to conduct the process design and improve the quality of the casting. Therefore, in or
8、der to achieve the air intake hood casting production, simulation of the filling and solidification process in the casting was carried on in this article. First of all, the plaster mould investment casting process of the new air intake hood was simple analyzed in this article. On this basis, the thr
9、ee-dimensional geometric modeling of the air intake hood was established by the software Pro/E. At last, the whole process of filling and solidification of the air intake hood was simulated by the casting simulation software ProCAST. The lack of filling, wrapped cold insulation, the location of the
10、gas and the hot spot and the residual stress and deformation were accurately displayed in this process. Under the process parameters of this simulation, the filling rate of the casting was 98%, the number and the distribution of other defects could basically meet the final using requirements of the
11、casting. So, the modeling working process of the new air intake hood can be considered into the application of the industrial production. Also, the casting process of the air intake hood can be optimized by the analysis of the defects. Thereby, the effective measures can be taken before the actual production to reduce or avoid the defects. It is of certain significance to the actual production of the enterprises. Key Words： air intake hood； plaster mould investment casting； solidification temperature field； filling flow field； numerical simulation
