摘要
研究了添加Yb和Zr元素对Al7Si0.3Mg合金组织及力学性能的影响,以及细化变质机理。结果表明,Yb、Zr元素的添加明显细化了α-Al基体,使其从粗大的树枝状晶转变为细小的花瓣状晶,晶粒尺寸明显减小,并且使共晶硅由粗大的针状变质为短棒状,这是由于Yb、Zr吸附在孪晶凹槽处(TPRE)改变共晶硅生长方式,最终改变共晶硅形貌;经热处理(T6)后,大量析出的Al_(3)(Yb,Zr)粒子起到了沉淀强化进而细化晶粒的作用。当Yb质量分数为0.3%、Zr质量分数为0.25%时,合金(T6)的抗拉强度和延伸率为296.3 MPa和9.2%,较未细化变质的合金分别提高了17%和1.1倍。
The effects of adding Yb and Zr elements on the microstructure and mechanical properties of Al7Si0.3Mg alloy and the mechanism of refinement and modification were investigated.The results show that the addition of Yb and Zr elements can significantly refine theα-Al matrix,transforming it from coarse dendritic crystals to fine petal-like crystals with a significant reduction in grain size,and the eutectic silicon metamorphoses from coarse needle-like to short rod-like.The modification mechanism of eutectic silicon is that the adsorption of Yb and Zr at the twin grooves(TPRE)changes the eutectic silicon growth mode and finally changes the eutectic silicon morphology.After heat treatment(T6),a large number of Al_(3)(Yb,Zr)particles are precipitated to strengthen and refine the grain,and the addition of Yb and Zr can significantly improve the mechanical properties of the alloy.The tensile strength and elongation of the alloy(T6)are 296.3 MPa and 9.2%when the Yb content is 0.3wt%and the Zr content is 0.25wt%,which are 17%and 1.1 times higher than those of the unrefined and unmodified alloy,respectively.
作者
吉全鑫
杜景红
张艺杰
李玉章
冯炜光
孙彦华
严继康
甘国友
Ji Quanxin;Du Jinghong;Zhang Yijie;Li Yuzhang;Feng Weiguang;Sun Yanhua;Yan Jikang;Gan Guoyou(Faculty of Materials Science and Engineering,Kunming University of Science and Technology,Yunnan 650093,China;Kunming Metallurgy Research Institute Company Limited,Yunnan 650031,China;School of Engineering,Southwest Petroleum University,Nanchong 637001,China)
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2022年第10期3580-3587,共8页
Rare Metal Materials and Engineering
基金
Major Science and Technology Project in Yunnan Province-New Material Special Project (202102AB080004, 2018ZE005, 2019ZE001)
Yunnan Province Transformation Research Institute Technology Development Research Project-Innovation Guidance and Technology Enterprise Cultivation Plan(202102AB080004)。
