半固态改性6061铝合金流变压铸试样组织及力学性能
Microstructures and Mechanical Properties of Semi-solid Modified 6061 Aluminum Alloy Samples by Rheo-diecasting
张荣晟 1毛卫民 1李乃拥1
作者信息
- 1. 北京科技大学材料科学与工程学院,北京 100083
- 折叠
摘要
采用石墨质蛇形通道浇注复合流变压铸工艺进行半固态改性6061铝合金流变压铸成形.对比分析了传统液态压铸和流变压铸的改性6061铝合金试样的显微组织;研究了Si含量对半固态改性6061铝合金流变压铸试样组织及力学性能的影响.结果表明,相比于传统液态压铸,半固态改性6061铝合金流变压铸试样组织中的初生α-Al晶粒明显细化和球化,由粗大的枝晶演变为细小的球状晶或近球状晶.增加Si含量可以有效细化试样组织中的初生α-Al晶粒,并提升流变压铸试样的力学性能,当Si含量由0.6%增加至2.6%时,初生α-Al的平均晶粒直径由58 μm左右逐渐减小至31 μm左右,抗拉强度由(107±4)MPa逐渐增加至(209±14)MPa,伸长率由2.2%±0.3%逐渐增加至5.5%±0.5%.
Abstract
The rheological high pressure die casting process(Rheo-HPDC)samples of semi-solid modified 6061 alu-minum alloy were prepared by graphite serpentine channel pouring process(SCP)and Rheo-HPDC.The microstruc-ture of 6061 aluminum alloy formed by traditional die casting and rheo-diecasting was analyzed comparatively.The effects of Si content on the microstructure and mechanical properties of Rheo-HPDC samples of semi-solid modified 6061 aluminum alloys were investigated.The results indicate that compared with the traditional die casting,the micro-structure of primary α-Al grains in the Rheo-HPDC samples of semi-solid modified 6061 aluminum alloys are signifi-cantly improved and refined,which is evolved from coarse dendrites to fine spherical or subspherical crystals.The pri-mary α-Al grains can be effectively refined and the mechanical properties can be improved with increasing in the Si con-tent.When Si content is increased from 0.6%to 2.6%,the average grain diameter of primary α-Al grains is decreased approximately from 58 μm to 31 μm,the tensile strength is increased from(107±4)MPa to(209±14)MPa,and elongation is increased from 2.2%±0.3%to 5.5%±0.5%.
关键词
6061铝合金/半固态流变压铸/显微组织/力学性能Key words
6061 aluminum alloy/Semi-solid rheo-diecasting/Microstructure/Mechanical properties引用本文复制引用
基金项目
国家自然科学基金资助项目(51771032)
出版年
2024
NETL
NSTL
万方数据