搅拌摩擦加工制备的闭孔泡沫铝的组织及性能  

Microstructure and properties of closed-cell aluminum foams prepared by friction stir processing

作　　者：庞秋[1] 吴正健 PANG Qiu;WU Zheng-jian(Department of Mechanical and Electrical Engineering,Wuhan Donghu University,Wuhan 430212,China;Hubei Key Laboratory of Advanced Technology for Automotive Components,Wuhan University of Technology,Wuhan 430070,China;Hubei Collaborative Innovation Center for Automotive Components Technology,Wuhan University of Technology,Wuhan 430070,China;Hubei Research Center for New Energy&Intelligent Connected Vehicle,Wuhan University of Technology,Wuhan 430070,China)

机构地区：[1]武汉东湖学院机电工程系,湖北武汉430212 [2]武汉理工大学现代汽车零部件技术湖北省重点实验室,湖北武汉430070 [3]武汉理工大学汽车零部件技术湖北省协同创新中心,湖北武汉430070 [4]武汉理工大学湖北省新能源与智能网联车工程技术研究中心,湖北武汉430070

出　　处：《塑性工程学报》2023年第1期140-147,共8页Journal of Plasticity Engineering

基　　金：湖北省自然科学基金资助项目(2021CFB523);湖北省教育厅科学研究计划(B2020245);湖北省重点研发计划(2020BAB140)。

摘　　要：为避免传统方法制备大面积闭孔泡沫铝工艺过程的局限性,采用搅拌摩擦加工技术结合加热工艺制备闭孔泡沫铝复合材料。采用有限元软件对搅拌摩擦加工制备预制体过程的温度场进行了模拟仿真,研究了制备工艺参数对泡沫铝预制体质量的影响规律。利用光学金相显微镜对不同加工工艺参数及发泡时间条件下制备的泡沫铝孔隙率和形貌进行了分析。同时,对闭孔泡沫铝进行了准静态压缩性能试验,研究了不同孔隙率下泡沫铝的压缩性能。结果表明,与搅拌针移动速度相比,不同旋转速度对闭孔泡沫铝预制体的形貌影响更大。当搅拌针移动速度50 mm·min^(-1)、旋转速度2000 r·min^(-1)时,焊核区金属和夹层中的混合粉末发生了充分的塑性变形,粉末圈分布连续且均匀。模拟结果表明:搅拌摩擦加工时最高温度区域出现在搅拌针附近,呈“碗状”分布,此时温度达到最大值491℃,焊核区金属和夹层中的混合粉末发生充分塑性变形和流动,模拟结果与试验结果一致。经过680℃发泡后,泡沫铝最大孔隙率为69.3%,平均泡孔直径为Φ130μm,屈服应力为3.2 MPa,平台应力值为2.9 MPa。To avoid the limitation of the traditional method of preparing large-area closed-cell aluminum foams,the closed-cell aluminum foam composite material was prepared by the friction stir processing(FSP)combined with heating process.The temperature field in FSP process of prefabricated parts was simulated using finite element software to study the influence rule of preparation process parameters on the quality of aluminum foam precursor.The porosities and morphologies of aluminum foam prepared with different processing parameters and foaming time were analyzed by optical metallographic microscope(OM).At the same time,the quasi-static compression properties tests of closed-cell aluminum foam were performed to investigate the compressive properties of aluminum foam with different porosities.The results show that compared with the moving speed of the stirring needle,different rotating speeds have a greater influence on the shape of closed-cell aluminum foam precursor.When the moving speed of the stirring needle is 50 mm·min^(-1) and the rotating speed is 2000 r·min^(-1),the mixed powder in the metal and interlayer in the weld core area has sufficient plastic deformation,and the powder ring distributionis is continuous and uniform.The simulation results show that the highest temperature area appears near the stirring needle during FSP,and the distribution is“bowl”shape.At this time,the maximum temperature reaches 491℃.The sufficient plastic deformation and flow occurr in the mixed powder in the metal and interlayer in the weld core area,and the simulation results are in good agreement with the test results.After foaming at 680℃,the maximum porosity of aluminum foam is 69.3%,and the average pore diameter isΦ130μm,the yield stress is 3.2 MPa,and the platform stress is 2.9 MPa.

关 键 词：功能材料 泡沫铝 搅拌摩擦加工 微观组织 

分 类 号：TG44[金属学及工艺—焊接]