高洁净度Al-5Ti-1B晶粒细化剂的制备与微结构特征

在传统氟盐法工艺的基础上,利用电磁场作用下合金化处理、旋转除气及高效过滤等技术,提出了一种制备高洁净度Al-5Ti-1B晶粒细化剂的新工艺。试验研究表明,采用新的高洁净度制备工艺使Al-5Ti-1B合金中的杂质减少、洁净度大幅度提高。微结构表征显示采用新工艺制备的Al-5Ti-1B合金中TiAl3相和TiB2粒子分布均匀,尺寸细小,分别为5～30μm和0.37～1.24μm,能够很好地满足高品质铝合金细化处理的要求。并对Al-5Ti-1B细化剂的细化机理进行了讨论,为工业生产中进一步提高Al-5Ti-1B细化剂的质量提供理论依据和技术参考。

Preparation of High Purity Al-5Ti-1B Grain Refiner and Its Microstructural Characteristics

A novel preparing technique for producing high purity Al-5Ti-1B grain refiner was presented by using processes including alloying with electronic and magnetic stirring,rotational degassing and high efficient filter,based on the traditional process of complex halide salts with molten aluminum.The results show that the impurity contents have been obviously decreased,and purity of Al-5Ti-1B alloy is greatly increased by using the new high-cleanliness process.Compared with the traditional method of "complex halide salts with molten aluminum",microstructural characterizations reveal that the intermetallic TiAl3 and TiB2 phases have small size of 5~30 μm and 0.37~1.24 μm,respectively,become more homogeneous distribution in Al-5Ti-1B master alloys prepared by "high-cleanliness process",which had met the requirements of refining treatment of high quality Al alloys.The refinement mechanism of the Al-5Ti-1B refiner was also discussed,which provided a theoretical basis and technical support for further improving the quality of Al-Ti-B grain refiner in industry.