铸态铝镁合金棒坯镦粗裂纹缺陷分析及消除措施  

Analysis and elimination measures on upsetting crack defects for as-cast Al-Mg alloy bar billet

作　　者：王玉弟 房超[2,3] 刘恒 李保先 亓效刚 王广春[2,3] Wang Yudi;Fang Chao;Liu Heng;Li Baoxian;Qi Xiaogang;Wang Guangchun(Shandong Ruiye New Material Co.,Ltd.,Binzhou 251800,China;State Key Laboratory of Advanced Equipment and Technology for Metal Forming,Shandong University,Jinan 250061,China;Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education),ShandongUniversity,Jinan 250061,China)

机构地区：[1]山东瑞烨新材料有限公司,山东滨州251800 [2]山东大学金属成形高端装备与先进技术全国重点实验室,山东济南250061 [3]山东大学材料液固结构演变与加工教育部重点实验室,山东济南250061

出　　处：《锻压技术》2025年第2期1-6,共6页Forging & Stamping Technology

基　　金：山东省科技型中小企业创新能力提升工程项目(2022TSGC2122);山东省高端铝制造与应用创新创业共同体项目(BZGDL-XM-2024-02);国家自然科学基金资助项目(52475371)。

摘　　要：针对某大型环件用铝镁合金铸棒镦粗制坯过程中的开裂问题,通过表征分析裂纹缺陷处的合金元素和第二相化合物发现,裂纹区域存在较为明显的元素偏析现象,聚集了大量的Si、Mg元素,其组成的第二相化合物Mg_(2)Si与基体的结合强度相对较低,当变形程度较大时,坯料外圆拉应力明显增加,导致Mg_(2)Si相较多的区域萌生裂纹,并在继续塑性变形的过程中发生开裂。进一步研究发现,锻前热处理温度对Mg_(2)Si相的析出量及形貌具有直接影响,将锻前加热温度提高至540℃并保温8 h,可有效调控Mg_(2)Si相的析出量,从而避免铸态铝镁合金棒坯镦粗过程中裂纹的产生。For the cracking problem during the upsetting process of Al-Mg alloy cast bars for a large ring,through the characterization analysis on alloying elements and second-phase compounds at the crack defect,it was found that there was a significant element segregation phenomenon in the crack area with a large amount of Si and Mg elements gathered,the formed second-phase compound Mg_(2)Si had a relatively low bonding strength with the matrix.When the deformation degree was large,the tensile stress on the outer circle of billet increased significantly,leading to the initiation of cracks in the areas with more Mg_(2)Si phase and cracking during the process of continuous plastic deformation.The further study found that the heat treatment temperature before forging had a direct impact on the precipitation amount and morphology of Mg_(2)Si phase.If the heating temperature before forging was raised to 540℃and held for 8 h,the precipitation amount of Mg_(2)Si phase was effectively regulated,and the occurrence of cracks during the upsetting process of as-cast Al-Mg alloy bar billets was avoided.

关 键 词：大型环件 5083铝镁合金 镦粗裂纹 热处理 元素偏析 

分 类 号：TG316[金属学及工艺—金属压力加工]