层状金属界面空洞的形成与演化  

Formation and evolution of interface voids in laminated metal

作　　者：刘鑫 帅美荣[1] 谢广明[2] 李海斌[1] 李亮[1] Liu Xin;Shuai Meirong;Xie Guangming;Li Haibin;Li Liang(Engineering Research Center of Heavy Machinery Ministry of Education,Taiyuan University of Science and Technology,Taiyuan 030024,China;State Key Laboratory of Rolling and Automation,Northeastern University,Shenyang 110004,China)

机构地区：[1]太原科技大学重型机械教育部工程研究中心,山西太原030024 [2]东北大学轧制技术及连轧自动化国家重点实验室,辽宁沈阳110004

出　　处：《锻压技术》2022年第7期162-166,174,共6页Forging & Stamping Technology

基　　金：国家自然科学基金资助项目(52075357);山西省重点研发计划(201903D121043);轧制技术及连轧自动化国家重点实验室(东北大学)开放课题(2020RALKFKT013);山西省研究生教育改革研究课题(2020YJJG241);山西省研究生教育创新项目(2021Y709)。

摘　　要：异种金属在复合变形过程中由于金属特性差异以及塑性变形不同步,在界面处极易产生空洞缺陷,而空洞的形成和演化对于双金属间界面结合有着极为不利的影响。采用有限元仿真技术模拟了不同张力系数下不锈钢/碳钢复合钢筋变形过程中空洞的发展演变规律。结果表明:在4道次三辊“切线”孔型中,位于辊缝区域的金属为自由变形;在变形初期覆层金属产生翘曲,此时芯部金属的宽展较小,逐步形成界面空隙及空洞;微张力轧制促使空洞在第2道次中进一步扩大,然而微张力能够改善覆层金属的壁厚均匀度;在第3、4道次精整孔型中,空洞逐渐收缩消失,顺利完成轧制。复合界面的显微形貌表明,随着轧制温度的升高,界面氧化物分解,界面层空洞逐渐消失;当轧制温度高达1200℃时,界面深度差仅为3μm,复合效果较好。In the process of composite deformation for dissimilar metals,due to the different in metal properties and the asynchronous plastic deformation,it is easy to produce the void defects at the interface area,and the formation and evolution of void defects have an extremely adverse effect on the bimetallic interfacial bonding.Therefore,the development and evolution laws of voids in the deformation process for stainless steel/carbon steel composite rib under different tension coefficients were simulated by the finite element simulation technology.The results show that in the four passes with three-roll“tangent”feature,the metal in the roll gap area is in free deformation,and the cladding metal warps at the initial stage of deformation.At this time,the core metal has a small width,and the voids and voids are gradually formed at the interface.Moreover,the micro-tension rolling promotes the voids to expand further in the second pass,and the micro-tension improves the uniformity of wall thickness for the cladding metal.In the third and fourth passes of finishing,the voids gradually shrink and disappear,and the rolling process is successfully completed.The micro-morphologies of composite interface show that with the increasing of rolling temperature,the interface oxides are gradually decomposed,and the voids in the interface layer disappear.When the rolling temperature reaches 1200℃,the interface depth difference is only 3μm,and the composite effect is better.

关 键 词：层状金属 轧制 微张力 微观形貌 空洞 

分 类 号：TG331[金属学及工艺—金属压力加工]