压缩变形对2219铝合金网状残余结晶相细化行为的影响  

Effect of compressive deformation on refinement behaviors of reticulated residual crystal phase of 2219 aluminum alloy

作　　者：毛献昌 何海林 林土淦[1] 林海燕 韦俊 MAO Xianchang;HE Hailin;LIN Tugan;LIN Haiyan;WEI Jun(School of Automotive Engineering,Guangxi Transport Vocational and Technical College,Nanning 530023,China;Research Institute of Light Alloy,Central South University,Changsha 410083,China)

机构地区：[1]广西交通职业技术学院汽车工程学院,南宁530023 [2]中南大学轻合金研究院,长沙410083

出　　处：《材料科学与工艺》2024年第4期67-75,共9页Materials Science and Technology

基　　金：国家自然科学基金资助项目(52005518);广西自然科学基金资助项目(2020GXNSFAA159156);广西高校中青年教师科研基础能力提升项目(2023KY1152)。

摘　　要：网状残余结晶相(RRCPs)偏聚是影响2219铝合金构件力学性能的主要因素,研究其细化行为具有重要意义。为了探明RRCPs的破碎细化机理,本文开展了2219铝合金高温(510和530℃)和中低温(240℃)单向压缩实验,采用扫描电子显微镜(SEM)和透射电子显微镜(TEM)分别研究了两种变形温度条件下不同相对压缩量(Δh)对RRCPs破碎效果的影响。研究结果表明:高温变形条件下,RRCPs主要以拉断和溶解断裂的形式发生细化;当Δh超过60%时,RRCPs才被大量破碎,形成大量长条状粒子,但破碎的结晶相仍呈带状偏聚。中低温变形条件下,RRCPs的破碎效果较显著,主要以脆性断裂的形式发生破裂和细化;当Δh等于20%时,RRCPs即可产生明显的裂纹;而当Δh大于60%时,结晶相被破碎成大量等轴状粒子,且粒子的分布均匀性较好。综上,与高温压缩相比,中低温压缩更有利于RRCPs的破碎,这可为优化2219铝合金多向锻造工艺提供参考。The segregation of reticulated residual crystalline phases(RRCPs)is the main factor affecting the mechanical properties of 2219 aluminum alloy,and it is important to study its refining behavior.In order to reveal the refinement mechanism of RRCPs,unidirectional compression tests for 2219 aluminum alloy ingot in hot deformation(510℃and 530℃)and warm deformation(240℃)were carried out.The effects of different relative compression(Δh)on the crushing effect of RRCPs under two deformation temperature conditions were investigated by scanning electron microscopy(SEM)and transmission electron microscopy(TEM).The results showed that in hot deformation processes,RRCPs was mainly refined by stretching and dissolving.A large number of RRCPs were refined into rod⁃shaped particles only whenΔh exceeded 60%while the crushed particles showed banded segregation.Moreover,in the warm deformation process,the fragmentation effect of RRCPs was more significant,primarilly occuring through brittle fracture and refinement.Obvious cracks can be formed on the RRCPs whenΔh was 20%.In addition,the RRCPs was broken into equiaxed particles with high distribution uniformity whenΔh exceeded 60%.In conclusion,compared with hot compression,warm compression process is more conducive to the crushing of RRCPs,which can provide valuable insights for optimizing the multi⁃directional forging process of 2219 aluminum alloy.

关 键 词：2219铝合金 网状结晶相 变形温度 相对压缩量 细化机理 单向压缩实验 

分 类 号：TB31[一般工业技术—材料科学与工程]