钢铝复合铸造界面设计及组织调控  

Steel-Aluminum Composite Casting Interface Design and Organization Regulation

作　　者：范昊天 郭冰鑫 王宇 孔翔 徐宏[1] 毛红奎[1] 武俊腾 FAN Hao-tian;GUO Bing-xin;WANG Yu;KONG Xiang;XU Hong;MAO Hong-kui;WU Jun-teng(School of Materials Science and Engineering,North University of China,Taiyuan 030051,Shanxi,China)

机构地区：[1]中北大学材料科学与工程学院,山西太原030051

出　　处：《铸造》2023年第10期1250-1259,共10页Foundry

基　　金：山西省基础研究计划面上项目(202103021224179);山西省高等学校科技创新项目(2020L0319)。

摘　　要：钢/铝复合结构融合了钢和铝合金各自的优点,在工业生产尤其是汽车制造中被广泛应用。为了提高钢/铝复合界面的结合强度,本研究提出利用拓扑优化将钢基体表面设计成多孔点阵结构,熔融铝合金流入多孔结构,与钢基体形成机械咬合和冶金结合相配合的双向互穿界面,增加界面结合强度。本文研究了铸造方式、孔隙率、浇注温度对钢/铝界面显微组织和力学性能的影响。结果表明,挤压铸造有助于熔融铝合金充入多孔结构,宏观上钢/铝界面处不存在缝隙。从微观形貌观察,随着孔隙率的增加,挤压铸造下钢/铝界面处的缝隙逐渐减小,剪切强度逐渐增加,当孔隙率为70%,浇注温度为730℃时,钢/铝界面处不存在缝隙且无冶金结合。对孔隙率70%的点阵结构进行改进后,当熔融铝合金的浇注温度为760℃时,钢/铝界面形成厚度为2μm的Al_(4.5)FeSi相金属间化合物,钢/铝界面剪切强度为118.1MPa。The steel/aluminum composite structure combined the respective advantages of steel and aluminum alloy and was widely used in industrial production,especially in automotive manufacturing.In order to improve the bond strength of the steel/aluminum composite interface,this study proposed to use topology optimization to design the steel substrate surface into a porous dotted structure,and the molten aluminum alloy flows into the porous structure to form a bi-directional interpenetrating interface with the steel substrate in conjunction with mechanical occlusion and metallurgical bonding to increase the interfacial bond strength.In this paper,the effects of casting method,porosity and pouring temperature on the microstructure and mechanical properties of the steel/aluminum interface were investigated.The results showed that the extrusion casting helped the molten aluminum alloy to fll into the porous structure,and there was no gap at the steel/aluminum interface macroscopically.From microscopic morphology,with the increase of porosity,the gap at the steel/aluminum interface under extrusion casting gradually decreased and the shear strength gradually increased,and when the porosity was 70%and the pouring temperature was 730℃,there was no gap and no metallurgical bond at the steel/aluminum interface.After the improvement of the dot matrix structure with 70%porosity,when the casting temperature of molten aluminum alloy was 760℃,the intermetallic compound of Al_(4.5)FeSi phase with a thickness of 2μm was formed at the steel/aluminum interface,and the shear strength of the steel/aluminum interface was 118.1 MPa.

关 键 词：钢/铝复合铸造 拓扑优化 点阵结构 剪切强度 双相互穿界面 

分 类 号：TG249[金属学及工艺—铸造]