论文部分内容阅读
采用有限元分析软件Pro CAST模拟了IN792合金在叶轮熔模铸造工艺中的充型凝固过程,分析了在充型凝固过程中缺陷形成的原因,分别探究了不同的浇铸速度、浇铸温度和型壳温度对凝固过程所产生缺陷的影响,通过正交试验的方法得到了最佳的工艺并对其充型凝固过程进行了分析。模拟结果表明:叶轮中存在缺陷,且缺陷主要集中在叶片薄壁处;叶片薄壁处缩松的数量随着浇铸速度的增加而增加,即减小浇铸速度可以得到质量较好的铸件;随着浇铸温度的提高,缩松逐渐减少,但是叶片上的缩松减少到一定程度后趋于平稳,说明浇铸温度对于缩松来说在一定范围内所产生的影响较小;型壳温度对铸件的缩松有很大的影响,随着型壳温度的增大,叶片上的缩松随之增加;最终得到了一套最佳的工艺方案:浇铸温度1420℃,浇铸速度0.8 m·s-1,型壳预热温度350℃;采用该工艺后,铸件中疏松数量明显减少,单个疏松尺寸明显缩小。
The finite element analysis software Pro CAST was used to simulate the filling and solidification process of IN792 alloy during the process of impeller investment casting. The reasons for the formation of defects in the process of filling and solidification were analyzed. The effects of different casting speed, casting temperature, The influence of temperature on the defects caused by the solidification process, the optimum process was obtained by orthogonal test and the process of filling and solidification was analyzed. The simulation results show that there are defects in the impeller, and the defects are mainly concentrated in the thin wall of the blade. The amount of shrinkage at the thin wall of the blade increases with the increase of the casting speed, that is, the casting with better quality can be obtained by reducing the casting speed. With the increase of casting temperature, the shrinkage is gradually reduced, but the shrinkage on the blade is reduced to a certain extent and then tends to be stable. This shows that the influence of casting temperature on the shrinkage is smaller in a certain range. Of the shrinkage has a great impact, with the shell temperature increases, the leaf shrinkage increases; finally got a set of the best process: the casting temperature of 1420 ℃, the casting speed of 0.8 m · s- 1, Shell preheating temperature is 350 ℃; After using this technology, the number of looseness in castings is obviously reduced, and the size of single looseness is obviously reduced.