摘要
为了提高A356铝合金晶粒细化和变质细化的耦合效果.添加不同比例的AlTiB和Ce,T6热处理后,采用XRD、OM和TEM及力学性能测试,研究了复合处理对α-Al晶粒与共晶Si相的组织调控规律及力学性能提升机制.结果表明:AlTiB和Ce的耦合作用能够显著细化α-Al晶粒并改善共晶Si的形貌.添加0.9%AlTiB和0.3%Ce,α-Al二次枝晶间距由23.71μm细化至17.44μm,共晶Si的平均长度由22.3μm缩短至7.4μm,其形态由粗针状转变为圆棒状.原位析出的Ti_(2)Al_(20)Ce以弥散分布的形态存在基体中,与富Si相界面结合良好,形成高效异质形核位点;合金的抗拉强度、屈服强度、延伸率和布氏硬度分别达到288.5、189 MPa、4.9%和59.5 HB,与原始态铝合金相比分别提高了61.5%、23.8%、53.1%和29.4%.
In order to improve the coupling effect of grain refinement and metamorphic refinement of A356 aluminum alloy.The mechanism of the composite treatment of adding AlTiB and Ce on the organization regulation law ofα-Al grains and eutectic Si phase and the enhancement of mechanical properties were systematically investigated by using XRD,OM and TEM and mechanical property tests after heat treatment.The results showed that the coupling mechanism of AlTiB and Ce can significantly refine theα-Al grains and improve the morphology of eutectic Si.With the addition of 0.9%AlTiB and 0.3%Ce,α-Al secondary dendrite spacing refine from 23.71μm to 17.44μm,the average length of eutectic Si is shortened from 22.3μm to 7.4μm,and its morphology is transformed from a coarse needle-like shape to a rounded rod.The in-situ precipitated Ti_(2)Al_(20)Ce exists in the matrix in a diffusely distributed morphology,and combines well with the interface of the Si rich phase to form highly efficient heterogeneous nucleation sites;The tensile strength,elongation and Brinell hardness of the alloy in this composition reach 288.5 MPa,189 MPa,4.9%and 59.5 HB,respectively,which are 61.5%,23.8%,53.1%and 29.4%higher compared with the pristine state of the aluminum alloy,respectively.
作者
曹驰
杨依帆
韩剑
赵葵
胡一迪
王坤
CAO Chi;YANG Yi-fan;HAN Jian;ZHAO Kui;HU Yi-di;WANG Kun(School of Materials Science and Engineering,Lanzhou University of Technology,Lanzhou 730050;Zhejiang Vocational and Technical College of Industry and Trade,Wenzhou 325026;Wenzhou Ruiming Industrial Co.Ltd.,Wenzhou 325000)
出处
《兰州理工大学学报》
北大核心
2026年第1期1-7,共7页
Journal of Lanzhou University of Technology
基金
浙江省“尖兵领雁+X”科技计划项目(2025C03018)
温州市科研项目(ZZG2024002)
温州市特种泵阀材料重点实验室资助(2024ZDSYS)。
关键词
A356铝合金
晶粒细化
复合处理
力学性能
共晶Si改性
A356 aluminum alloy
grain refinement
composite modification
mechanical properties
eutectic Si modification
