稀土La改性6063铝合金的微观组织和时效性能的研究  

Study of Rare-earth La Modification on Microstructure and Aging Properties of 6063 Aluminum Alloys

作　　者：杨天恩[1] 熊计[1] 杨启平 徐红阳 

机构地区：[1]四川大学制造科学与工程学院,四川成都610065 [2]成都阳光铝制品有限公司,四川成都610100

出　　处：《热加工工艺》2016年第11期29-33,共5页Hot Working Technology

基　　金：四川省科技计划项目(2015GZ0057)

摘　　要：制备了含稀土La的6063铝合金,并研究了La含量对铝合金的显微组织及时效后硬度、抗拉强度和伸长率的影响。研究表明,稀土La对6063合金晶粒有良好的细化作用,在添加La的铝合金组织中,一部分较大的析出相是Al Si Mg Fe化合物,且铁含量较高;另一部分析出相是Al Si Mg Fe La的复杂化合物,其形状多呈较小的粒状。200℃等温时效时,随着时效时间的延长,铝合金硬度迅速升高,在120 min左右达到最大。同时,随着La含量的增加,合金的硬化峰值上升,当La含量为0.2 wt%左右时,时效硬化峰值达到最高。另外,加入适量La可增加合金的抗拉强度和伸长率。未添加La的铝合金其断口组织分布着较大的不规则韧窝,而添加少量La的铝合金其断口上细小的韧窝增多。The 6063 aluminum alloys with rare-earth La were prepared, and the effects of the La content on the microstructure and hardness, tensile strength as well as extensibility of the alloys were investigated. The results show the rare-earth La can make the grains of the 6063 aluminum alloys finer. Some of the larger precipitated phases in the microstructure are Al Si Mg Fe compounds with high Fe contents. The other precipitated ones are Al Si Mg Fe La compounds with small granular shapes. The hardness of the aluminum alloys is increased with the aging time increased at 200 ℃, and reach the maximum when 120 min is adopted. The peak of the hardening is also raised with the increase of La contents, and the peak is the highest caused by around 0.2 wt% of La. The tensile strength and extensibility of the alloys can be improved by appropriate La contents. Some large irregular dimples can be found in the fractured surfaces in the alloys without La,while more small dimples appear in the alloys with La.

关 键 词：铝合金 稀土La 析出相 时效硬化 断口组织 

分 类 号：TG166.3[金属学及工艺—热处理]