摘要
To improve the poor stability of casting process of Al alloy with high Mg content, which leads to poor final product quality, the melting purification process and the influences of the refiner on the microstructure and defect of 5083 alloy were studied. The results show that the optimized process for the rotary impeller degassing of 5083 alloy is as follows： a rotary speed of 250-400 r/min; a gas flow of 1.2-2.0 L/s, a refining time of 10-15 min. This optimized process can reduce the gas content in the solid alloy to 2× 10^-3 mL/g or lower. Due to the addition of grain refiner, the cast microstructure of 5083 alloy is refined. The Al-5Ti-IB wire shows the best refining effect among all the refiners. The refining effect is improved with the increase of grain refiner addition amount. And the refinement effects become stable when Ti content reaches 0.1% or higher. The surface crinkling defect of the billet can be easily found in the alloy refined with Al-5Ti-IB wire compared with the alloys refined with other refiners.
高镁铝合金大规格铸锭的铸造工艺不够稳定,从而影响最终产品质量.研究精炼、晶粒细化剂对5083铝合金组织和表面质量的影响.结果表明：5083合金旋转喷吹除气的优化精炼工艺为：转速250～400 r/min,气体流量1.2～2.0 L/s,精炼时间10～15 min.采用该优化的精炼工艺可使固体合金中气体含量降低至2×10^-3 mL/g以下.晶粒细化剂的加入可以使5083合金的铸态组织细化.在加入的所有细化剂中,Al-5Ti-1B丝具有最好的细化效果.随着细化剂加入量的增加,细化效果提高.当Ti含量大于0.1％,细化效果变化不大.与使用其它细化剂的合金相比,使用Al-5Ti-1B丝细化的合金表面很容易产生褶皱缺陷.
基金
Project(12511075)supported by the Foundation of Heilongjiang Education Committee,China
