热扭转变形对AZ80+0.4%Ce镁合金时效行为的影响
|
摘要
使用Gleeble-3500热模拟试验机对AZ80+0.4%Ce镁合金进行高温扭转试验,随后进行时效处理。扭转变形时变形量和应变速率与扭转试样半径呈正比关系,以此研究应变速率及应变量对后期时效效果的影响规律。结果表明:合金经扭转变形后晶粒得以细化,试样横截面形成梯度组织,边缘处的平均晶粒尺寸小于心部;AZ80+0.4%Ce镁合金时效初期,析出相较少,边缘与心部的差别不大;随时效时间的增加,边缘的第二相面积分数明显高于心部;峰值时效时,边缘第二相面积分数仍高于心部;在时效过程中边缘处的硬度值始终高于心部,说明高应变量及应变速率对细晶和时效强化起到促进作用。
Hot torsion deformation of AZ80+0.4%Ce magnesium alloy was tested by Gleeble-3500 thermal simulator,and then aging treatment was carried on.The strain and strain rate is directly proportional to the radius of specimen during torsion,which was proposed to study the influence of strain rate and strain effects on aging.The results show that the grains are refined after torsion,and gradient microstructure is observed at the cross section of the sample.The average grain size of the edge is smaller than that of the heart.There is less second phase and few difference between the edge and the heart of AZ80+0.4%Ce Mg alloy at the initial stage of aging;the area fraction of the second phase on the edge is obviously higher than that of the heart;and the second phase of the edge is still slightly higher than that of the heart until the post stage of aging.The hardness of the edge is always higher than that of the heart during aging and torsion,which means the effect of grain-refinement and aging strengthening is promoted by high strain and strain rate.
Hot torsion deformation of AZ80+0.4%Ce magnesium alloy was tested by Gleeble-3500 thermal simulator,and then aging treatment was carried on.The strain and strain rate is directly proportional to the radius of specimen during torsion,which was proposed to study the influence of strain rate and strain effects on aging.The results show that the grains are refined after torsion,and gradient microstructure is observed at the cross section of the sample.The average grain size of the edge is smaller than that of the heart.There is less second phase and few difference between the edge and the heart of AZ80+0.4%Ce Mg alloy at the initial stage of aging;the area fraction of the second phase on the edge is obviously higher than that of the heart;and the second phase of the edge is still slightly higher than that of the heart until the post stage of aging.The hardness of the edge is always higher than that of the heart during aging and torsion,which means the effect of grain-refinement and aging strengthening is promoted by high strain and strain rate.
引文
[1]陈振华.变形镁合金[M].化学工业出版社,2005:355-358.
[2]梁亚会,杨勇彪,王强,等.AZ80+0.4%Ce挤压态镁合金热成形行为研究[J].兵器材料科学与工程,2016,39(6):35-40.
[3]ZHU Qingfeng,LI Lei,ZHANG Zhiqiang.Microstructure evolution of AZ80 magnesium alloy during multi-directional forging process[J].Materials Transactions,2014,55(2):270-274.
[4]GUO Ning,SONG Bo,GUO Changfa,et al.Improving tensile and compressive properties of magnesium alloy rods via a simple pre-torsion deformation[J].Materials&Design,2015,83:270-275.
[5]王军,朱秀荣,徐永东,等.稀土Ce和Y对AZ80镁合金组织和力学性能的影响[J].中国有色金属学报,2014,24(1):25-35.
[6]李伟东,周海涛,陈和兴,等.变形、时效对AZ80镁合金组织性能的影响[J].特种铸造及有色合金,2011,31(12):1170-1174.
[7]ZHU Qingfeng,WANG Gaosong,ZHANG Enge,et al.Dynamic and static aging precipitation ofβ-Mg17Al12in the AZ80 magnesium alloy during multi-directional forging and subsequent aging[J].Acta Metallurgica Sinica(English Letters),2017,30(10):941-948.
[8]舒小港.扭转变形及热处理对镁合金力学性能与微结构演变的影响[D].重庆:重庆大学,2016.
[9]陈红兵.形变热处理和扭转变形对镁合金组织性能的影响[D].重庆:重庆大学,2016.
[10]齐红娜.热扭转变形Mg-Gd-Y-Zn-Zr合金的动态再结晶研究[D].太原:中北大学,2017.
[11]彭建,韩韡,彭毅,等.基于热扭转试验的ME21镁合金热变形行为研究[J].稀有金属,2014,38(3):341-347.
[12]刘聪,张芝民,李小霞,等.利用扭转变形制备高体积含量梯度结构材料的研究进展[J].热加工工艺,2017(9):28-32.
[13]DULY D,SIMON J P,BRECHET Y.On the competition between continuous and discontinuous precipitations in binary Mg-Al alloys[J].Acta Metallurgica Et Materialia,1995,43(1):101-106.
[14]LAI Weijen,LI Yiyun,HSU Yungfu,et al.Aging behaviour and precipitate morphologies in Mg-7.7Al-0.5Zn-0.3Mn(wt.%)alloy[J].Journal of Alloys&Compounds,2009,476(1/2):118-124.
[15]曹凤红,龙思远.时效处理对AZ81镁合金组织与力学性能的影响[J].热加工工艺,2010,39(8):159-162.
[16]ZHAO Degang,WANG Zhenqing,ZUO Min,et al.Effects of heat treatment on microstructure and mechanical properties of extruded AZ80 magnesium alloy[J].Materials&Design,2014,56(4):589-593.
[2]梁亚会,杨勇彪,王强,等.AZ80+0.4%Ce挤压态镁合金热成形行为研究[J].兵器材料科学与工程,2016,39(6):35-40.
[3]ZHU Qingfeng,LI Lei,ZHANG Zhiqiang.Microstructure evolution of AZ80 magnesium alloy during multi-directional forging process[J].Materials Transactions,2014,55(2):270-274.
[4]GUO Ning,SONG Bo,GUO Changfa,et al.Improving tensile and compressive properties of magnesium alloy rods via a simple pre-torsion deformation[J].Materials&Design,2015,83:270-275.
[5]王军,朱秀荣,徐永东,等.稀土Ce和Y对AZ80镁合金组织和力学性能的影响[J].中国有色金属学报,2014,24(1):25-35.
[6]李伟东,周海涛,陈和兴,等.变形、时效对AZ80镁合金组织性能的影响[J].特种铸造及有色合金,2011,31(12):1170-1174.
[7]ZHU Qingfeng,WANG Gaosong,ZHANG Enge,et al.Dynamic and static aging precipitation ofβ-Mg17Al12in the AZ80 magnesium alloy during multi-directional forging and subsequent aging[J].Acta Metallurgica Sinica(English Letters),2017,30(10):941-948.
[8]舒小港.扭转变形及热处理对镁合金力学性能与微结构演变的影响[D].重庆:重庆大学,2016.
[9]陈红兵.形变热处理和扭转变形对镁合金组织性能的影响[D].重庆:重庆大学,2016.
[10]齐红娜.热扭转变形Mg-Gd-Y-Zn-Zr合金的动态再结晶研究[D].太原:中北大学,2017.
[11]彭建,韩韡,彭毅,等.基于热扭转试验的ME21镁合金热变形行为研究[J].稀有金属,2014,38(3):341-347.
[12]刘聪,张芝民,李小霞,等.利用扭转变形制备高体积含量梯度结构材料的研究进展[J].热加工工艺,2017(9):28-32.
[13]DULY D,SIMON J P,BRECHET Y.On the competition between continuous and discontinuous precipitations in binary Mg-Al alloys[J].Acta Metallurgica Et Materialia,1995,43(1):101-106.
[14]LAI Weijen,LI Yiyun,HSU Yungfu,et al.Aging behaviour and precipitate morphologies in Mg-7.7Al-0.5Zn-0.3Mn(wt.%)alloy[J].Journal of Alloys&Compounds,2009,476(1/2):118-124.
[15]曹凤红,龙思远.时效处理对AZ81镁合金组织与力学性能的影响[J].热加工工艺,2010,39(8):159-162.
[16]ZHAO Degang,WANG Zhenqing,ZUO Min,et al.Effects of heat treatment on microstructure and mechanical properties of extruded AZ80 magnesium alloy[J].Materials&Design,2014,56(4):589-593.