Asymmetric Strain Fatigue Behavior and Life Prediction of 3.5NiCrMoV Steel and 20Cr13 Steel for Steam Turbine

WU Haili

doi:10.11973/jxgccl202109009

Materials and Mechanical Engineering > 2021 > 45(9): 45-50. > DOI: 10.11973/jxgccl202109009

WU Haili. Asymmetric Strain Fatigue Behavior and Life Prediction of 3.5NiCrMoV Steel and 20Cr13 Steel for Steam Turbine[J]. Materials and Mechanical Engineering, 2021, 45(9): 45-50. DOI: 10.11973/jxgccl202109009

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Asymmetric Strain Fatigue Behavior and Life Prediction of 3.5NiCrMoV Steel and 20Cr13 Steel for Steam Turbine

WU Haili

Shanghai Electric Power Generation Equipment Co., Ltd., Shanghai 200240, China

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Received Date: May 12, 2020
Revised Date: April 15, 2021

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Abstract

Symmetric and asymmetric strain control fatigue tests were performed on 3.5NiCrMoV bainite steel and 20Cr13 martensite steel for steam turbine, and their fatigue behaviors were compared and studied. Morrow model, SWT model and Ellyin model based on symmetric strain fatigue parameters were used to predict asymmetric fatigue life, and the applicability of these models was discussed. The results show that the asymmetric fatigue life of 3.5NiCrMoV steel was not higher than its symmetric fatigue life, and the asymmetric fatigue life of 20Cr13 steel was higher than its symmetric fatigue life. There was a big difference between symmetric and asymmetric cyclic stresses of 3.5NiCrMoV steel, and the symmetric and asymmetric cyclic stresses of 20Cr13 steel were similar. The average stress reduction was a common phenomenon for asymmetric strain control fatigue, and the plastic strain change was the main factor affecting asymmetric fatigue life. The prediction accuracy of the Morrow model depended on the effect of strain ratio on fatigue life. The SWT model was not suitable for fatigue life prediction of 3.5NiCrMoV steel with a large difference between asymmetric and symmetric cyclic stress-strain curves. The Ellyin model had a good prediction effect on the asymmetric fatigue life of 20Cr13 steel with similar asymmetric and symmetric cyclic hardening trends.
- asymmetric strain fatigue,
- average stress,
- strain ratio,
- life prediction,
- steam turbine steel

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[1]	李舜酩. 机械疲劳与可靠性设计[M]. 北京:科学出版社, 2006. LI S M. Mechanic fatigue and reliability design[M]. Beijing:Science Press, 2006.
[2]	MANSON S S. Behaviors of materials under condition of the thermal stress:NACA TN-2933[R].[S.l.]:National Advisory Committee for Aeronautics, 1954.
[3]	COFFIN L F. A study of the effects of cyclic thermal stresses on a ductile metal:KAPL-853[R].[S.l.]:Knolls Atomic Power Lab, 1954.
[4]	MORROW J D. Fatigue design handbook-advances in engineering[M]. Warrendale, PA:Society of Automotive Engineers, 1968:21-29.
[5]	SMITH K N, WATSON P, TOPPER T H. Stress-strain function for the fatigue of metals[J]. Journal of Materials, 1970, 5(4):767-778.
[6]	ELLYIN F, KUJAWSKI D. An energy-based fatigue failure criterion[M].[S.l.]:EAMS, 1986:541-600.
[7]	张孝忠, 王恭义, 程凯, 等.一种考虑平均应力松弛的汽轮机叶根低周疲劳寿命预测方法[J].材料科学与工程学报.2019, 37(5):709-713. ZHANG X Z, WANG G Y, CHENG K, et al. LCF life prediction method of turbine blade roots considering mean stress relaxation effect[J].Journal of Materials Science and Engineering, 2019, 37(5):709-713.
[8]	吴德龙.载荷模式对9-12%Cr钢高温低周疲劳行为影响及循环本构研究[D]. 上海:华东理工大学, 2016. WU D L. Effect of control mode on high temperature low cycle fatigue behavior of 9-12%Cr steel and cyclic constitutive modeling[D]. Shanghai:East China University of Science and Technology, 2016.
[9]	田阳, 陈巍峰, 赵姿贞, 等.应变比对2.25Cr1MoV钢高温低周疲劳行为的影响[J].机械工程材料.2015, 39(11):83-87. TIAN Y, CHEN W F, ZHAO Z Z, et al. Effect of strain ratio on low cycle fatigue behavior of 2.25Cr1MoV steel at high temperature[J]. Materials for Mechanical Engineering, 2015, 39(11):83-87.
[10]	张仕朝, 于慧臣, 李影.不同应变比下GH3030合金的高温低周疲劳行为[J].机械工程材料.2014, 38(1):56-59. ZHANG S C, YU H C, LI Y, et al. Low cycle fatigue behavior of a superalloy GH3030 at elevated temperature and different strain ratios[J]. Materials for Mechanical Engineering, 2014, 38(1):56-59.
[11]	张仕朝, 李旭东, 于慧臣, 等.DD6合金1100℃低周疲劳行为[J]. 航空材料学报.2018, 38(1):95-100. ZHANG S C, LI X D, YU H C, et al. Low cycle fatigue of single crystal nickel-based superalloy DD6 at 1100℃[J]. Journal of Aeronautical Materials, 2018, 38(1):95-100.
[12]	KOH S K, STEPHENS R I. Mean stress effects on low cycle fatigue for a high strength steel[J]. Fatigue and Fracture of Engineering Materials and Structures, 1991, 14(4):413-428.
[13]	吴海利, 安春香, 王朋, 等.2.25CrMoV钢于夹杂物和晶界开裂的低周疲劳裂纹扩展行为原位观测[J].机械工程材料, 2016, 40(3):15-18. WU H L, AN C X, WANG P, et al. In situ crack propagation behavior observation at inclusions and grain boundary of 2.25CrMoV steel under low cycle fatigue[J]. Materials for Mechanical Engineering, 2016, 40(3):15-18.
[14]	ARMAS A F, PETERSEN C, SCHMITT R, et al. Cyclic instability of martensite laths in reduced activation ferritic/martensitic steels[J].Journal of Nuclear Materials, 2004, 329:252-256.

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Asymmetric Strain Fatigue Behavior and Life Prediction of 3.5NiCrMoV Steel and 20Cr13 Steel for Steam Turbine

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