摘要
通过低倍组织、显微组织观察,能谱分析和凝固性能分析研究了含Zn的3xxx系铝合金扁锭羽毛晶缺陷的组织形貌及Zn元素对羽毛晶缺陷的影响。结果表明：含Zn的3xxx系铝合金扁锭的羽毛晶呈丛生长条状晶,交错分布,具有孪晶组织特征,且羽毛晶中的化合物相粗大,分布不均匀,分布密度小,而正常等轴晶区域的化合物相细小,分布弥散均匀,分布密度大。在3xxx系铝合金扁锭中添加Zn元素,可以改善正常等轴晶中化合物相偏聚的现象,减少对基体的割裂作用;但Zn元素的添加不仅未改善羽毛晶中化合物相的析出状态,反而扩大了合金的结晶温度区间,使得铸造过程中容易出现异常过冷,增加了羽毛晶的产生倾向。在含Zn 3xxx系铝合金铸锭的生产中,需注意Zn元素的添加操作,防止含Zn 3xxx系铝合金铸锭中羽毛晶缺陷的产生。
The morphology of feathery grains defect and effect of Zn on feathery grains defect of 3 xxx series aluminum alloy slab ingot containing Zn were investigated by ways of macrostructure, microstructure observation, energy spectrum analysis and solidification performance analysis. The results show that the feathery grains are a group of long strip crystal with staggered distribution and twin microstructure characteristics, and the compound phases in feather crystal are coarse, uneven and have low density. While the compound phases in the normal equiaxed crystal region are small, uniform and have high density. The addition Zn element in 3 xxx series aluminum alloy slab ingot can improve the partial segregation of compound phases in normal isometric crystals and reduce the separation of the matrix, while it doesn＇t improve precipitation state of compound phases in feathery grains and increase formation tendency of feathery grains by enlarging crystallization temperature range and be easy to produce abnormal supercooling during the casting process. In the production of 3 xxx series aluminum alloy ingots containing Zn, it needs to pay attention to the addition of Zn to prevent the formation of feathery grains defect in 3 xxx series aluminum alloy ingots containing Zn.
作者
蒋秋妹
饶庆东
刘俊生
顾沛沛
JIANG Qiumei;RAO Qingdong;LIU Junsheng;GU Peipei(Guangxi Alnan Aluminum Fabrication Co., Ltd., Nanning 530031, China)
出处
《热加工工艺》
CSCD
北大核心
2018年第9期254-256,259,共4页
Hot Working Technology
基金
南宁科技攻关计划(20151280)
关键词
3xxx系铝合金
扁锭
羽毛晶
Zn元素
3xxx series aluminum alloy
slab ingot
feathery grains
Zn element
