Effects of rotating impeller degassing on microstructure and mechanical properties of the A356 scraps
Effects of rotating impeller degassing on microstructure and mechanical properties of the A356 scraps
复制标题
旋转叶轮除气对A356废钢显微组织和力学性能的影响
DOI：
10.1016/s0921-5093(02)00900-0
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发表时间：
2003
期刊：
影响因子：
6.4
通讯作者：
W. Ding
中科院分区：
文献类型：
--
作者：
H. Ni;Bao;Haiyan Jiang;W. Ding
采用旋转叶轮脱气技术对经JDN-Ⅰ型稀土熔剂保护净化的A356废熔体进行脱气处理。结果表明，旋转叶轮除气后，共晶硅变质作用减弱，合金力学性能变差;经JDN-1熔剂精炼后，再经旋转叶轮除气系统处理的A356合金，其抗拉强度和伸长率分别比单独用该熔剂精炼时下降了5.6%和23.3%。其机理是旋转叶轮脱气增加了熔体中的氧含量，降低了熔体中的氢含量，消耗了含稀土熔剂中的更多稀土。因此，对共晶硅变质有影响的稀土含量低于临界值。同时，熔体中的氧化物夹杂物增加，导致合金力学性能下降。
The rotating impeller degassing technique was used for degassing of A356 scrap melt which had been protected and purified with an RE-containing JDN-I flux. Results indicated that the modification of eutectic silicon was faded and the mechanical properties of the alloy became worse after rotating impeller degassing and that the tensile strength and elongation of the scrap A356 alloy which was treated with rotating impeller degassing system after having been refined by JDN-I flux decreased by 5.6 and 23.3%, respectively, compared with those of being refined merely with the flux. The mechanism is that the rotating impeller degassing increases the oxygen content and decreases the hydrogen content of the melt, consuming more rare earth from the RE-containing flux. Thus, the content of rare earth that has effect on the modification of eutectic silicon is lower than the critical value. At the same time, the oxide inclusions in the melt increase leading to a drop of mechanical properties of the alloy.