研究不同精炼工艺对铸造Al-2Li-2Cu-0.2Zr 合金夹杂物和力学性能的影响,包括双级C2Cl6 精炼工艺,双级氩气旋转喷吹精炼工艺和双级复合精炼工艺。结果表明,结合C2Cl6 和氩气旋转喷吹的双级复合精炼工艺可以显著提高铸造Al-2Li-2Cu-0.2Zr 合金的熔体纯净度和力学性能。与未精炼的合金相比,通过双级复合精炼工艺得到的合金气孔缺陷和夹杂物的体积分数从1.47%下降到0.12%,固溶处理后合金的屈服强度、抗拉强度和伸长率分别从113 MPa、179 MPa 和3.9%提高至142 MPa、293 MPa 和18.1%。合金熔炼过程中,在加入锂之前首先使用C2Cl6 精炼进行除气以及除掉熔体中较大尺寸的夹杂物,在加入锂之后使用氩气旋转喷吹进一步除气以及除掉熔体中细小的悬浮夹杂物。双级复合精炼工艺不仅可以有效去除熔体中的气体和夹杂物,还可以大幅度降低锂元素的氧化烧损,结合两种精炼方法的各自优势,取得显著的精炼效果。
The effect of different refining processes on inclusions and mechanical properties of cast Al-2Li-2Cu-0.2Zr alloy was investigated, including two-stage hexachloroethane (C2Cl6) refining process, two-stage rotating gas bubbling refining process and two-stage composite refining process. It was found that the two-stage composite refining process, which combined C2Cl6 and rotating gas bubbling, can significantly improve the melt purity and mechanical properties of cast Al-2Li-2Cu-0.2Zr alloy. Compared to the unrefined alloy, the volume fraction of gas porosity defects and slag inclusions decreased from 1.47% to 0.12%, and the yield strength, ultimate tensile strength and elongation of as-quenched alloy increased from 113 MPa,179 MPa and 3.9% to 142 MPa, 293 MPa and 18.1%, respectively. C2Cl6 was first utilized to degas and remove large size slag inclusions before lithium addition, and then the rotating gas bubbling was utilized to do the further degassing and remove the suspended fine inclusions after lithium addition. The two-stage composite refining process can take advantage of two methods and get the remarkable refining effect.
Transactions of Nonferrous Metals Society of China
Project (2016YFB0301003) supported by the National Key R&D Program of China
Project (51871148) supported by the National Natural Science Foundation of China
Project (sklmmc-kf18-02) supported by Open Research Fund of the State Key Laboratory of Metal Matrix Composites, China.
Corresponding author:Liang ZHANG,Tel:+86-13661663183,E-mail:firstname.lastname@example.org;Corresponding author:Guo-hua WU,Tel:+86-13671800698,E-mail:email@example.com.