累积连续流变挤压对Al-Mg(-Mn-Fe)合金组织性能影响  

Effect of Accumulative Continuous Extrusion Forming on Microstructure and Properties of Al-Mg(-Mn-Fe)Alloys

作　　者：高民强 杨博威 管仁国 GAO Minqiang;YANG Bowei;GUAN Renguo(Engineering Research Center of Continuous Extrusion,Ministry of Education,Dalian Jiaotong University,Liaoning Dalian 116028,China)

机构地区：[1]大连交通大学连续挤压教育部工程研究中心,辽宁大连116028

出　　处：《精密成形工程》2024年第7期215-223,共9页Journal of Netshape Forming Engineering

基　　金：松山湖材料实验室开放课题基金(2023SLABFN11);国家重点研发计划(2022YFE0137900)。

摘　　要：目的研究多道次累积连续流变挤压变形对Al-Mg(-Mn-Fe)合金组织演化和力学行为的影响,为高性能细晶Al-Mg(-Mn-Fe)合金的制备提供借鉴与参考。方法采用连续流变挤压方法制备Al-Mg(-Mn-Fe)合金,对流变挤压态Al-Mg(-Mn-Fe)合金进行多道次累积连续流变挤压变形,研究多道次变形前后Al-Mg(-Mn-Fe)合金的微观组织和力学性能变化,讨论变形过程中Al_(6)(Mn,Fe)相对动态再结晶的影响,揭示累积连续流变挤压态Al-Mg(-Mn-Fe)合金的强化机制。结果经3道次累积连续流变挤压变形后,Al-Mg合金和Al-Mg-Mn-Fe合金的平均晶粒尺寸分别减小至21.5μm和2.8μm,细化效果显著;在多道次变形过程中,Al-Mg-Mn-Fe合金内的Al_(6)(Mn,Fe)相逐渐破碎细化并趋于均匀分布,再结晶驱动力增加,阻碍再结晶晶粒长大;经3道次变形后,Al-Mg合金杆材的抗拉强度和伸长率同步提高至267.4 MPa和52.2%,而Al-Mg-Mn-Fe合金杆材的抗拉强度提高至364.2 MPa,伸长率降低至31.7%,该合金的强化机制主要包括细晶强化、位错强化和第二相强化。结论累积连续流变挤压变形可有效细化合金内的晶粒及第二相,提高Al-Mg(-Mn-Fe)合金的综合力学性能。The work aims to investigate the effect of multi-pass accumulative continuous extrusion forming(ACEF)on the microstructure evolution and mechanical behavior of Al-Mg(-Mn-Fe)alloys,to provide references for the preparation of fine-grained Al-Mg(-Mn-Fe)alloys with high performance.Al-Mg(-Mn-Fe)alloys were prepared by ACEF.The variation in microstructure and mechanical properties of Al-Mg(-Mn-Fe)alloys subject to multi-pass ACEF was studied.The effect of Al_(6)(Mn,Fe)phase particles on dynamic recrystallization during deformation was discussed.The strengthening mechanisms of ACEFed Al-Mg(-Mn-Fe)alloys were revealed.The results showed that significant grain refinement effect was achieved in the Al-Mg alloy and Al-Mg-Mn-Fe alloy subject to 3 passes ACEF,and the average grain size decreased to 21.5μm and 2.8μm,respectively.The Al_(6)(Mn,Fe)phase particles in the Al-Mg-Mn-Fe alloy were gradually broken,refined,and uniformly distributed during multi-pass ACEF.Thus,the driving force of dynamic recrystallization was enhanced and the growth of recrystallized grains was hindered.After 3 passes ACEF,the ultimate tensile strength and elongation of Al-Mg alloy rods increased to 267.4 MPa and 52.2%,respectively.Meanwhile,the ultimate tensile strength of Al-Mg-Mn-Fe alloy rods increased to 364.2 MPa and the elongation decreased to 31.7%.The strengthening mechanisms of the alloys mainly included fine-grained strengthening,dislocation strengthening and second phase strengthening.ACEF can refine the grains and secondary phase particles,and improve the comprehensive mechanical properties of the alloys.

关 键 词：Al-Mg(-Mn-Fe)合金 累积连续流变挤压 变形道次 组织性能 

分 类 号：TB31[一般工业技术—材料科学与工程]