AZ31B挤压变形镁合金低周疲劳行为研究.pdf

第31卷第4期
沈阳航空航天大学学报
Vol 31 No.4
2014年8月
Journal of Shenyang Aerospace University
Aug.2014
文章编号:2095-1248(2014)04-0044-06
AZ31B挤压变形镁合金低周疲劳行为研究
耿长建,武保林,刘芳,佟文伟,韩振宇
(1.中国航空工业集团公司阳发动机设计研究所材料应用研究室,沈阳110015:
2.沈阳航航天大学材料科学与.程学院,沈阳10136)
摘要:分判研究了挤压変形AZB1B镁合金在非对称載荷与对称载倘下的疲劳行为,结果明种加
载方式下,波劣过程随着应变幅的增加,滞回曲线的不对称性均増?;在低应变幅下,位错滑移为主
要剴性变形机制;前在较高应变幅下,李牛-ム牛为主要变形机制;同一成变幅下,压一压非对称
低应変幅疲劳寿命最长,拉-压对称低应变幅疲劳寿命次之,拉一拉对称低应变皜疲劳寿命最短
关键词;AZ31B镁合金;滞同曲线;位错滑移;生-去生
中图分类号
文献标志码
doi:10.3969/j-1iss.2095-1248.20]14.04.009
Study on the low cycle fatigue behavior of extruded AZ1 B
magnesium alloy
GENG Chang-jian WU Bao-lin, LIU Fang, TONG Wen-wei, HAN Zhen-yu
( 1. Application materials research Laboratory, AICC Shenyang Engine Design and Research Institute Shenyang 110015, China
2. School of Materials Science and Engineering, Shenyang Aerospace University, Shenyang 110136, China)
Abstract: The paper focuses on the low cycle fatigue behavior of AZ31B magnesium alloy under symmetric
and asymmetric loading. The results show that the asymmetry of the hysteresis is enhanced with strain ampli
tude increasing. At lower strain amplitude, dislocation slip is the dominant plastic deformation mechanism re
sponsible for cyclic hardening At high strain amplitude, twinning- detwinning is the key deformation mech-
anism. During the cyclic fatiguc, the clastic strain of the tensile process is larger than that of compressive
process. At the same strain amplitude, the longest fatigue life is under incompressive-compressive asymmet
ric loading, followed by that under the tensile-compressive symmetric loading, and the shortest is under the
tensile-tensile asymmetric loading
Key words AZ31 B magnesium alloy; hysteresis loop; dislocation lip; twinning-detwinning
镁合金具有密度低、比强度和比刚度高,良好压变形镁合金,被用在发动机输油管路及机匣中
的铸造性能、较强的电磁屏蔽能力以及易于再生.不同的加载方向下,AZ31B变形镁合金呈现各向
利用等一系列独特的优点,被誉为“21世纪最具异性。最近,许多对镁合金在应变制的低周疲
发展潜力和前途的材料”。其结构件在汽车、飞劳的研究表明,加载方式和样品的织构对其疲劳
机、计算机、通讯等领域获得了日益广泛的应性能具有重要影响“。研究表明,镁合金低周
用-3。由于具有良好的延展率和较高的强度等疲劳过程中每周期都发生孪生-去李生行为,该
优点,AZ31B变形铁合金是目前应用最广泛的挤行为在镁合金疲劳巾起重要作用。然而,在
收稿日期:2014-05-15
基金项目:家白然科学基金(项编号:5117120:090202001)
作者笛介:耿长建(1980-),男,山东聊城人,博十,工师、卞要从事航卒发动机材科疲芳行为及微观变形机制研究,E-mail
gengchangjian2008c 163 com
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