摘要
研究了Sb对A356合金中共晶Si相的变质作用及RE对Sb变质作用的影响,并且与Sr变质合金进行了比较,对Sb、Sb+RE以及Sr变质A356合金的拉伸及疲劳性能进行了对比。结果表明,Sb的A356合金变质使共晶Si相由粗大的板片状转化为细小的纤维状,但变质效果不如Sr;用Sb变质处理时,加入少量的RE,可明显改善Sb的变质效果,降低获得最佳变质效果的Sb含量;合金变质的力学性能不如Sr变质合金,但疲劳性能明显优于Sr变质合金。其原因可能与Sb或Sb+RE变质合金的致密性较Sr变质合金高、铸造缺陷较Sr变质合金少有关。
The modification of antimony （Sb） on eutectic 51 phase m A356 aiummum-silicon alloy and the effects of rare earth （RE） on the modification efficiency of antimony were investigated, and effects of the strontium （St） on A356 alloy were analyzed comparatively. The tensile and fatigue properties of the Sb, Sb＋RE or Sr modified A356 alloys were also analyzed comparatively. The results show that Sb can re- fine the euteetie silicon phases in A356 alloy significantly from plate-like into fine fibrous structure. However, the modification efficiency of Sb is lower than Sr. The modification effects can be improved obviously in Sb modified A356 aluminum-silicon alloy with the addition of a little RE, decreasing of Sb content for achieving the desirable modification efficiency. The tensile properties of the Sb or Sb＋ RE modified A356 alloys are lower than those of the Sr modified alloy, however, the fatigue properties are superior to that of the Sr modified alloy, which may be attributed to the higher compactness and less casting defects in Sb or Sb＋RE modified alloys compared with the Sr modified alloy.
出处
《特种铸造及有色合金》
CAS
CSCD
北大核心
2012年第12期1098-1102,共5页
Special Casting & Nonferrous Alloys
关键词
A356合金
Sb变质
RE
共晶Si相
A356 Alloy, Sb Modification, Rare Earth （RE）, Eutectic Silicon Phase
