K4648合金中空盲管薄壁件无余量精密铸造工艺研究

Research for Investment Casting of the Thin-Walled Tubular Components Made of K4648 Superalloy

K4648合金梁为某型号航空发动机尾喷口的核心部件,采用无余量精密铸造工艺铸造而成。该部件为大尺寸中空盲管薄壁件,长度约450mm,管壁厚2.5~3mm。该铸件在铸造过程极易产生疏松和裂纹缺陷,冶金质量难以控制,此外该部件在铸造过程中变形较大,尺寸精度控制困难。针对该部件冶金质量控制及变形等问题,本文对梁部件熔模制备方案、浇注系统设计、浇注工艺及铸件校形工艺等方面进行了系统的研究,研制的K4648合金梁铸件冶金质量优良、尺寸精确。

The girder, which is made of K4648 superalloy by investment casting, is one of the core components of the aeroengine. The length of the thin-walled tubular components is about 450 mm, and the thickness of the tube wall is about 2.5~3mm. The porosity, crack and deforming can be easily found in the process of casting, therefore the metallurgical quality and dimensional accuracy of this part is hard to be guaranteed. In order to solve these problems, the process of lost wax, gating system, casting and shape-righting is thorough researched in this paper. The prepared girder which is made of K4648 superalloy is excellent in metallurgical quality and accurate in size.