您目前所在的位置:首页 - 期刊简介 - 详细页面

铁道科学与工程学报

JOURNAL OF RAILWAY SCIENCE AND ENGINEERING

Vol. 16    No. 6    December 2006

[PDF Download]    [Flash Online]

    

Effect of large cold deformation after solution treatment on precipitation characteristic and deformation strengthening of 2024 and 7A04 aluminum alloys
NING Ai-lin(宁爱林)1, 2, LIU Zhi-yi(刘志义)1, ZENG Su-min(曾苏民)1,2

1. School of Materials Science and Engineering, Central South University, 
Changsha 410083, China; 
2. Department of Machinery Engineering, Shaoyang Institute, Shaoyang 422000, China

Abstract: The effects of large cold deformation after solution treatment on the precipitation characteristic and deformation strength of 2024 and 7A04 Al alloys were investigated. The tensile property tests indicate that the ageing response of the 2024 aluminum alloy is accelerated when treated by cold deformation after solution treatment, and the tensile strength is increased to about 140 MPa while the elongation still keeps above 8%. However, compared with the 2024 alloys, although the aging response of the cold deformed 7A04 aluminum alloy is accelerated, the tensile strength has not changed obviously and the elongation is even decreased drastically. The results of TEM observation show that the S′ phase inside the dislocation cells and at the boundaries of the dislocation cells of the 2024 aluminum alloy has a uniform distribution. But in 7A04 aluminum alloy the club-shaped η′ phase forms at the boundaries of dislocation cells even on dislocation lines, while there still exists small spheric G.P zone in the region with less dislocation. In addition the precipitates in 7A04 alloy with cold rolling present more obvious tendency of growth and coarsening than those without cold rolling. It is indicated that the coherent strain energy of the cylinder formed G.P zones with matrix in the 2024 alloy is smaller than that of the spherical G.P zone in 7A04 alloy, for which a different distribution of precipitates and different effect of strengthening are caused in artificial ageing after resolution treatment and large cold deformation.

 

Key words: aluminum alloy; aging precipitation; strengthening; cold deformation

ISSN 1672-7029
CN 43-1423/U

主管:中华人民共和国教育部 主办:中南大学 中国铁道学会 承办:中南大学
湘ICP备09001153号 版权所有:《铁道科学与工程学报》编辑部
------------------------------------------------------------------------------------------
地 址:湖南省长沙市韶山南路22号 邮编:410075
电 话:0731-82655133,82656174   传真:0731-82655133   电子邮箱:jrse@mail.csu.edu.cn