大批量冶炼定向凝固高温合金的工艺研究

Study on Mass Smelting Process for Directionally Solidified Superalloy

摘要对型号为VIDP400的3吨真空炉大批量冶炼DZ417G定向高温合金的冶炼工艺进行研究，分析了影响组织均匀性和稳定性的主要因素以及对高温拉伸和持久性能的影响。结果表明：通过调整大容积流道，缓解来自坩埚中钢水的冲击，使得钢水液面高度较低以及较大的表面积同时加电磁搅拌使合金中氧、氮含量均大幅降低。拉晶速率在，4．5～8．5mm·min，在1220℃固溶和980℃时效制度处理后可获得均匀的组织，高温拉伸强度可达750MPa，延伸率为17％，面缩为22％。

Large quantities of VIDP400 vacuum furnace smelting DZ417G oriented superalloys smelting process have been researched, analysis of the main factors affecting the organizational uniformity and stability, as well as the impact of high temperature tensile and lasting properties, has been studied. The results showed that by adjusting the high volume flow channel to alleviate the impact from the crucible of molten steel, molten steel surface had a low height and larger surface area of the molten steel adding the electromagnetic stir- ring, oxygen and nitrogen content of the alloy were sharply reduced. At pulling rate of 4. 5--8.5 mm·min-1 , after 1 220℃ and 980 ℃ aging system, the available treatment uniform struc- ture would be obtained, with a high-temperature tensile strength up to 750 MPa, an elongation of 17% and a reduction of area with 22%.