Discussion of Models for Low Cycle Fatigue Damage Evolution of Magnesium Alloys
-
摘要: 通过铸造镁合金AZ91D和变形镁合金AZ31B室温环境应力控制的低周疲劳试验，基于连续损伤力学，选取平均应变的变化作为损伤变量，将镁合金的低周疲劳损伤演化划分为损伤初始阶段、损伤稳定阶段和循环末期的快速损伤阶段，各阶段的损伤分别以形核损伤、微裂纹损伤和主裂纹损伤为主。在此基础上建立了三阶段损伤模型和两阶段损伤模型，并用上述损伤模型进行了镁合金的低周疲劳损伤演化分析。研究结果表明：相对于经典的低周疲劳损伤模型，采用三阶段损伤模型和两阶段损伤模型所得损伤曲线与试验结果符合较好，能较好地反映镁合金低周疲劳损伤的演化过程。Abstract: Through low cycle fatigue experiments of the cast magnesium alloy AZ91D and the wrought magnesium alloy AZ31B at room temperature under stress control, the low cycle fatigue damage evolution of magnesium alloys was divided into the initial damage stage, the stable damage stage and the rapid damage stage at the end of the cycle by selecting the change of the mean strain as the damage variable based on the continuum damage mechanics. And the damage of each stage above mentioned was mainly caused by nucleation damage, micro-crack damage and main crack damage respectively. On this basis, the three stage damage model and the two stage damage model were developed. And then, the low cycle fatigue damage evolution was analyzed by using the above-mentioned damage models. Results show that comparing with the classic model for low cycle fatigue damage, the damage curves obtained by the three stage damage model and the two stage damage model are in a better agreement with the experimental, and which can better reflect the low cycle fatigue damage evolution process of magnesium alloys.
-
Key words:
- magnesium alloy /
- low cycle fatigue /
- damage evolution /
- damage variable /
- damage model
-
表 1 铸造镁合金AZ91D与变形镁合金AZ31B室温25 ℃低周疲劳试验数据及结果
试样 材料 加载频率/Hz 名义应力幅σa/MPa 疲劳寿命Nf 1-1# AZ91D 3 80 14 752 1-2# AZ91D 3 90 5 124 1-3# AZ91D 3 100 2 562 1-4# AZ91D 3 110 512 1-5# AZ91D 3 120 61 2-1# AZ31B 5 75 23 524 2-2# AZ31B 5 80 10 579 2-3# AZ31B 5 90 6 376 2-4# AZ31B 5 100 1 018 2-5# AZ31B 5 110 113 
下载: 导出CSV
表 2 铸造镁合金AZ91D低周疲劳损伤模型拟合结果
试样 经典低周疲劳损伤模型(式(4)) 两阶段损伤模型(式(13)) 三阶段损伤模型(式(11)) k Di m n k Di m n Ds k b 1-1# 0.0396 0.084 285.7926 0.5913 0.0118 0.084 285.7926 0.5913 0.0801 0.1786 3208.4561 1-2# 0.0599 0.0919 45.5061 0.453 0.0227 0.0919 45.5061 0.453 0.0982 0.1995 1159.8705 1-3# 0.0723 0.0887 150.2992 0.6446 0.036 0.0887 150.2992 0.6446 0.1588 0.2655 634.3669 1-4# 0.0964 0.085 44.1088 0.5899 0.051 0.085 44.1088 0.5899 0.167 0.3309 114.4265 1-5# 0.1099 0.0984 3.4008 0.2969 0.0525 0.0984 3.4008 0.2969 0.0998 0.3710 36.4015
下载: 导出CSV
表 3 变形镁合金AZ31B低周疲劳损伤模型结果
试样 经典低周疲劳损伤模型(式(4)) 两阶段损伤模型(式(13)) 三阶段损伤模型(式(11)) k Di m n k Di m n Ds k b 2-1# 0.054 0.0679 7.9867 0.2672 0.0318 0.0679 7.9867 0.2672 0.1516 0.3431 6873.389 2-2# 0.0645 0.0638 6.2804 0.255 0.0442 0.0638 6.2804 0.255 0.1807 0.4008 1562.9689 2-3# 0.0755 0.0629 7.0574 0.2827 0.0531 0.0629 7.0574 0.2827 0.2007 0.4231 1199.4738 2-4# 0.1211 0.0955 6.9256 0.4214 0.0746 0.0955 6.9256 0.4214 0.1886 0.4901 203.5928 2-5# 0.1496 0.0701 10.3944 0.6186 0.1026 0.0701 10.3944 0.6186 0.2465 0.5142 85.2423
下载: 导出CSV
-
[1] Li H Z, Lv F, Xiao Z Y, et al. Low-cycle fatigue behavior of a cast Mg-Y-Nd-Zr alloy by T6 heat treatment[J]. Materials Science and Engineering:A, 2016, 676:377-384 doi: 10.1016/j.msea.2016.09.001 [2] Yu D L, Zhang D F, Sun J, et al. High cycle fatigue behavior of extruded and double-aged Mg-6Zn-1Mn alloy[J]. Materials Science and Engineering:A, 2016, 662:1-8 doi: 10.1016/j.msea.2016.02.079 [3] Chen G, Gao J W, Cui Y, et al. Effects of strain rate on the low cycle fatigue behavior of AZ31B magnesium alloy processed by SMAT[J]. Journal of Alloys and Compounds, 2018, 735:536-546 doi: 10.1016/j.jallcom.2017.11.141 [4] Pan J P, Peng L M, Fu P H, et al. The effects of grain size and heat treatment on the deformation heterogeneities and fatigue behaviors of GW83K magnesium alloys[J]. Materials Science and Engineering:A, 2019, 754:246-257 doi: 10.1016/j.msea.2019.03.063 [5] Wang C, Luo T J, Yang Y S. Low cycle fatigue behavior of the extruded AZ80 magnesium alloy under different strain amplitudes and strain rates[J]. Journal of Magnesium and Alloys, 2016, 4(3):181-187 doi: 10.1016/j.jma.2016.07.002 [6] 刘新东, 郝际平.连续介质损伤力学[M].北京:国防工业出版社, 2011Liu X D, Hao J P. Continuum damage mechanics[M]. Beijing:National Defense Industry Press, 2011(in Chinese) [7] 郑修麟, 王泓, 鄢君辉, 等.材料疲劳理论与工程应用[M].北京:科学出版社, 2013Zheng X L, Wang H, Yan J H, et al. Fatigue theory and engineering applications of materials[M]. Beijing:Science Press, 2013(in Chinese) [8] Lin Y C, Liu Z H, Chen X M, et al. Stress-based fatigue life prediction models for AZ31B magnesium alloy under single-step and multi-step asymmetric stress-controlled cyclic loadings[J]. Computational Materials Science, 2013, 73:128-138 doi: 10.1016/j.commatsci.2013.02.023 [9] Lin Y C, Chen X M, Liu Z H, et al. Investigation of uniaxial low-cycle fatigue failure behavior of hot-rolled AZ91 magnesium alloy[J]. International Journal of Fatigue, 2013, 48:122-132 doi: 10.1016/j.ijfatigue.2012.10.010 [10] Gryguc A, Behravesh S B, Shaha S K, et al. Low-cycle fatigue characterization and texture induced ratcheting behaviour of forged AZ80 Mg alloys[J]. International Journal of Fatigue, 2018, 116:429-438 doi: 10.1016/j.ijfatigue.2018.06.028 [11] Geng C J, Wu B L, Du X H, et al. Low cycle fatigue behavior of extruded AZ31B magnesium alloy[J]. Transactions of Nonferrous Metals Society of China, 2013, 23(6):1589-1594 doi: 10.1016/S1003-6326(13)62635-7 [12] Song L H, Wu B L, Zhang L, et al. Cyclic deformation behaviors of AZ31B magnesium alloy in two different asymmetric loading manners[J]. Materials Science and Engineering:A, 2017, 689:134-141 doi: 10.1016/j.msea.2017.02.046 [13] 宋松, 韩永典, 徐连勇, 等.基于混合硬化模型的Ti-6Al-4V低周疲劳损伤分析[J].焊接学报, 2019, 40(1):43-48 http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=hjxb201901009Song S, Han Y D, Xu L Y, et al. Analysis on low cycle fatigue damage of Ti-6Al-4V based on combined hardening model[J]. Transactions of The China Welding Institution, 2019, 40(1):43-48(in Chinese) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=hjxb201901009 [14] 陈凌, 张贤明, 欧阳平.一种基于连续损伤力学的低周疲劳寿命预测模型[J].中国机械工程, 2015, 26(18):2506-2510, 2517 http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=zgjxgc201518017Chen L, Zhang X M, Ouyang P. A life prediction model for low cycle fatigue based on continuum damage mechanics[J]. China Mechanical Engineering, 2015, 26(18):2506-2510, 2517(in Chinese) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=zgjxgc201518017 [15] 陈凌, 张贤明, 刘飞, 等.镁合金低周疲劳寿命预测模型探讨[J].中国机械工程, 2017, 28(5):512-518 http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=zgjxgc201705002Chen L, Zhang X M, Liu F, et al. Discussion of low cycle fatigue life prediction models for magnesium alloys[J]. China Mechanical Engineering, 2017, 28(5):512-518(in Chinese) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=zgjxgc201705002 [16] 中华人民共和国国家质量监督检验检疫总局, 中国国家标准化管理委员会.GB/T 15248-2008金属材料轴向等幅低循环疲劳试验方法[S].北京: 中国标准出版社, 2008General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China, Standardization Administration of China. GB/T 15248-2008 The test method for axial loading constant-amplitude low-cycle fatigue of metallic materials[S]. Beijing: Chinese Standard Press, 2008(in Chinese) [17] 陈凌, 张贤明, 刘飞, 等.AZ91D室温环境棘轮及其低周疲劳行为[J].材料科学与工程学报, 2017, 35(5):741-746 http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=clkxygc201705011Chen L, Zhang X M, Liu F, et al. Ratcheting and low cycle fatigue behavior of AZ91D at room temperature[J]. Journal of Materials Science and Engineering, 2017, 35(5):741-746(in Chinese) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=clkxygc201705011 [18] Shiozawa K, Kitajima J, Kaminashi T, et al. Low-cycle fatigue deformation behavior and evaluation of fatigue life on extruded magnesium alloys[J]. Procedia Engineering, 2011, 10:1244-1249 doi: 10.1016/j.proeng.2011.04.207 [19] Begum S, Chen D L, Xu S, et al. Low cycle fatigue properties of an extruded AZ31 magnesium alloy[J]. International Journal of Fatigue, 2009, 31(4):726-735 doi: 10.1016/j.ijfatigue.2008.03.009 [20] 陈凌, 张贤明, 刘飞, 等.镁合金非对称应力载荷下的低周疲劳损伤演化和寿命预测[J].中国机械工程, 2019, 30(6):748-755 http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=zgjxgc201906018Chen L, Zhang X M, Liu F, et al. Damage evolution and life prediction of low cycle fatigue for magnesium alloys under asymmetrical stress loading[J]. China Mechanical Engineering, 2019, 30(6):748-755(in Chinese) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=zgjxgc201906018 [21] 程光旭, 韦玮, 李光哲.复合材料疲劳损伤演化的两阶段模型[J].机械工程材料, 2000, 24(5):1-4 http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=jxgccl200005002Cheng G X, Wei W, Li G Z. A general two stage model for accumulation of fatigue damage in composite materials[J]. Materials for Mechanical Engineering, 2000, 24(5):1-4(in Chinese) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=jxgccl200005002 [22] 黄云云, 刘康林.超高压管道的疲劳损伤研究[J].福州大学学报, 2010, 38(4):563-567 http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=fzdxxb201004020Huang Y Y, Liu K L. Fatigue damage study of the ultrahigh-pressure pipe line[J]. Journal of Fuzhou University, 2010, 38(4):563-567(in Chinese) http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=fzdxxb201004020 -
点击查看大图
图(8) / 表(3)
计量
- 文章访问数: 133
- HTML全文浏览量: 24
- PDF下载量: 13
- 被引次数: 0
