摘要
采用金相显微镜、X-射线衍射分析仪和电子探针研究了Cr含量渊质量分数分别为0、0.2%、0.4%、0.6%和0.8%冤对含1.2%Fe的A356合金的铸态显微组织的影响。结果表明,当合金中未加入Cr时,显微组织中存在着大量的粗大针状铁相;当合金中加入0.2%Cr时,合金中粗大的针状Fe相开始出现断裂分叉现象,同时针状Fe相的长度变短,而Fe相形貌并没有明显的改变;当Cr含量增加至0.4%时,针状Fe相逐渐转变为细小汉字状;当Cr含量超过0.6%时,Fe相则变成粗大的鱼骨状甚至块状。因此,要获得较佳的铸态显微组织,Cr的加入量约为0.4%-0.6%。
The effects of the content of Cr （mass fraction is 0%, 0.2%, 0.4%, 0.6% and 0.8% respectively） on as-cast microstructure of A356 alloys containing 1.2% Fe were studied by using of metallurgical microscope,X-ray diffraction analysis and electric probe. The results indicate that, when the alloy is not added Cr, there are large amount of thick needlelike iron phases in the microstructure; when the alloy is added 0.2%Cr, the thick needlelike iron phases begin to break and the length of the needlelike iron phase reduces at the same time, but the pattern of iron phase has not changed obviously; when the Cr content increases to 0.4%, the needlelike Fe phases gradually transforme into small Chinese characters; when the Cr content exceeds 0.6%, Fe phase becomes coarse herringbone or even block. Therefore, to acquire better as-cast microstructure, the addition amount of Cr is about 0.4%-0.6%.
出处
《热加工工艺》
CSCD
北大核心
2014年第11期62-64,71,共4页
Hot Working Technology
