Microstructure damage evolution associated with cyclic deformation for extruded AZ31B magnesium alloy
Microstructure damage evolution associated with cyclic deformation for extruded AZ31B magnesium alloy
复制标题
挤压 AZ31B 镁合金与循环变形相关的微观组织损伤演化
DOI：
10.1016/j.msea.2016.08.043
复制
发表时间：
2016-10
期刊：
影响因子：
6.4
通讯作者：
Xiong, Ying
中科院分区：
文献类型：
--
作者：
Xiong, Ying
研究了挤压态AZ31B镁合金在应变控制拉压载荷下沿挤压方向不同应变幅值下的疲劳损伤演化规律，观察到不同的循环变形行为。当应变幅值为2%时，拉伸峰值应力表现出明显的循环软化，而压缩峰值应力表现出一致的循环硬化。在1%时，拉伸峰值和压缩峰值应力均出现中度循环硬化。在0.5%时，拉伸峰值应力呈现稳定的循环硬化，而压缩峰值应力几乎保持不变。利用扫描电子显微镜（SEM）分析了与循环变形相关的微观组织形态。用归一化参数λ分析x射线衍射（XRD），评价变形孪晶的程度。结果表明，疲劳裂纹的萌生模式和扩展模式与应变幅值有关。当加载强度为2%时，在第一次加载循环后出现晶界（GB）开裂和三节理开裂。在1%时，疲劳裂纹在晶界（GB裂纹）、孪晶界（TB裂纹）和相邻三晶粒的三重接合处萌生。晶界诱导（gb诱导）的晶间扩展模式和持续滑移带诱导（psb诱导）的穿晶扩展模式在早期裂纹扩展中起重要作用。在0.5%时，裂纹萌生模式与1%时相似，但早期裂纹扩展以gb诱导的晶间扩展模式为主。讨论了组织（织构、晶粒尺寸和均匀性）对疲劳损伤行为的影响。
Fatigue damage evolution of extruded AZ31B magnesium (Mg) alloy is investigated under strain-controlled tension-compression loading along the extrusion direction at various strain amplitudes, and the different cyclic deformation behaviors are observed. At the strain amplitude of 2%, the tensile peak stress displays significant cyclic softening, whereas the compressive peak stress shows consistent cyclic hardening. At 1%, moderate cyclic hardening is observed at both the tensile peak and compressive peak stresses. At 0.5%, the tensile peak stress presents stable cyclic hardening, whereas the compressive peak stress almost keeps constant. The microstructure morphologies associated with the cyclic deformation are analyzed by scanning electronic microscope (SEM). The degree of deformation twins is evaluated by analyzing X-ray diffraction (XRD) using a normalized parameterλ. The results show the fatigue crack initiation modes and its propagation modes are dependent on the strain amplitude. At 2%, grain boundary (GB) cracking and triple joint cracking are detected after 1st loading cycle. At 1%, fatigue crack initiates at grain boundary (GB cracking), twin boundary (TB cracking) and triple joint of three neighboring grains. Both grain boundary induced (GB-induced) intergranular and persistent slip band induced (PSB-induced) transgranular propagation modes play an important role in the early-stage crack growth. At 0.5%, crack initiation modes are similar to that at 1%, but GB-induced intergranular propagation mode dominates the early-stage crack growth. The effects of the microstructure (texture, grain size and uniformity) on the fatigue damage behavior are discussed.
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DOI：
10.1007/s11661-002-0150-1
发表时间：
2002
期刊：
Metallurgical and Materials Transactions A
影响因子：
--
作者：
M. Yoo;J. R. Morris;K. Ho;S. Agnew
通讯作者：
M. Yoo;J. R. Morris;K. Ho;S. Agnew
DOI：
10.1016/j.msea.2008.02.003
发表时间：
2008-09
影响因子：
6.4
作者：
Fan Yang;S. Yin;S. Li;Zhefeng Zhang
通讯作者：
Fan Yang;S. Yin;S. Li;Zhefeng Zhang
影响因子：
9.4
作者：
L. Wu;S. Agnew;D. Brown;G. M. Stoica;B. Clausen;A. Jain;D. Fielden;P. Liaw
通讯作者：
L. Wu;S. Agnew;D. Brown;G. M. Stoica;B. Clausen;A. Jain;D. Fielden;P. Liaw
DOI：
10.1016/j.msea.2012.10.048
发表时间：
2013-01
影响因子：
6.4
作者：
Fenghua Wang;Jie Dong;Yanyao Jiang;W. Ding
通讯作者：
Fenghua Wang;Jie Dong;Yanyao Jiang;W. Ding
DOI：
10.4028/www.scientific.net/msf.539-543.3407
发表时间：
2007-02
期刊：
Materials Science Forum
影响因子：
--
作者：
D. Brown;A. Jain;S. Agnew;B. Clausen
通讯作者：
D. Brown;A. Jain;S. Agnew;B. Clausen