TC4合金陶瓷模粉末冶金工艺研究

Ceramic Mold Powder Metallurgy Process of TC4 Alloy

目的研究陶瓷模粉末冶金工艺,通过数据积累指导未来工程化应用。方法通过氧化钇陶瓷模壳技术,研究构件与铸件的化学成分、力学性能及微观组织。结果粉末件在包套高度方向上金属收缩率明显大于包套水平方向的收缩率;粉末构件内部质量良好,无夹杂,其致密度达到了99.5%;粉末构件室温力学性能优于同成分铸件,部分室温力学性能达到TC4锻件水平。结论采用稀土氧化钇面层、硅溶胶铝矾土背层涂料工艺得到的陶瓷型可用于陶瓷型壳粉末冶金工艺;构件尺寸收缩率在每个方向上不是均匀的,和其在包套内放置方向、包套放置方向都有关系;构件晶粒细小均匀,组织为由细小的魏氏体板条α相与相间β相、等轴α相所组成,等轴α相分布不均匀,主要分布在晶界上;其构件室温力学性能优于同成分铸件力学性能,部分性能达到了锻件水平。

The paper aims to study powder metallurgy process of ceramic mold to guide the future engineering application with data accumulation. The chemical composition, mechanical properties and microstructure of components and castings were studied by yttrium oxide ceramic shell technology. The shrinkage rate of the metal in the high direction of the cladding was ob-viously greater than that in the horizontal direction of the cladding; the internal quality of the powder components was good, and the density was 99.5%. The mechanical properties at room temperature were better than that of castings of the same component; and the mechanical properties at room temperature reach TC4 forgings. The ceramic mold produced by the rare earth oxide sur-face layer and the silica sol bauxite back coating process could be used in the ceramic shell powder metallurgy process. The shrinkage rate of the component size is not uniform in every direction, and it is related to the direction of the package and the direction of the package. The structure of the component is fine and uniform and the microstructure is fine. The alpha phase of Wei＇s body is composed of phase beta phase and equiaxed alpha phase, and the distribution of equiaxed alpha phase is uneven, mainly on grain boundary, and the mechanical properties of the components are better than the mechanical properties of the same components at room temperature, and some properties have reached the forging level.