新型细化剂AlTiBRE中间合金的纯净化处理效果研究

Study on the effect of purification of a new AlTiBRE grain refiner

采用铝熔体熔剂净化技术对Al5Ti1B0.5RE中间合金细化剂熔体进行净化处理试验,优化出合适的排杂熔剂及其处理工艺,并采用OM、SEM、EDAX等进行夹杂物及细化相粒子的存在形态和成分分析.结果表明,XHJ1熔剂的净化效果好,与未净化的相比,除杂率达82.4%.当XHJ1熔剂加入量2%,处理温度750℃时细化剂中含杂量少,夹杂物数量也少、尺寸细小且弥散分布.有效的净化对改善细化剂中细化相粒子的分布形态起重要作用,即经净化后细化相粒子TiAl3分布更为均匀且多呈细小块状、平均尺寸11.16μm,TiB2相粒子呈疏松状均匀分布、平均尺寸3.28μm,此外还揭示了其改善的原因.

A new Al5Ti1B0.5RE master alloy refiner melt was treated with the high-efficient purification technology by the flux for removing inclusions,and the flux composition and its treament technology were optimized.At the same time,the existing form and chemical compositions of the inclusions and the refinment particles in the master alloy were analyzed with aids of OM,SEM,EDAX and XRD etal.The results indicated that the purification effect of XHJ1 flux was excellent.Comparing with that of no treatment,the rate of removing inclusion was up to 82.4%.the content of inclusions was the few,and the fine and dispersive TiAl3 phase distributed homogeneously in molten aluminum under the condition of temperature of 750 ℃ and the addition 2wt%.The effective purification had the important effect on improving the existing form of refinement particles in the refiner.That is,TiAl3 phase particles in the refiner distributed more homogeneously and dispersively after purification,the average size of TiAl3 phase was about 11.16 μm,and the TiB2 particles in the master alloy distributed homogeneously without congregation,the average size of TiB2 phase was about 3.28 μm.Besides,the cause of the improvement was expounded at last.