A 3D wheel-rail transient rolling contact model has been developed in consideration of rail decarburization layers using the explicit finite element method. The actual 3D geometry of wheel and rail, material nonlinearity and high-frequency dynamic interactions between vehicle and track are all taken into account. A penalty method based surface-to-surface contact algorithm is implemented to solve the transient wheel-rail rolling contact in the time domain, with which the normal and tangent contact solutions are obtained for any instants. Through comparison it is found that the existence of decarburization layer would increase the plastic deformation, resulting in larger contact patch and adhesion area, smaller normal and tangential contact stresses and lower frictional work. Due to the limited depth of the decarburization layer, being typically less than 1 mm, its influence on the shape and size of the contact patch is negligible, while those on contact stresses, adhension-slip distinction and frictional work are noticeable. A thicker decarburization layer could increase the plastic deformation of top layers of elements, while the plastic deformation of the first layer of element is lowered because of the redistribution of plastic deformation among the top layers. For longitudinally intermittent decarburization layers, the wheel-rail contact force and contact stresses all show noticeable variations at the boundaries between the decarburized and parent sections. Taking the running from a decarburized section to a parent one as an example, in which parameters of decarburization layer measured from an actual rail are used, the excited dynamic wheel-rail forces are 0.32 and 1.14 kN in the vertical and longitudinal directions, respectively, and the normal and tangential contact stresses and the frictional work are 4.42%, 19.71% and 83.19% larger than their stable values on the decarburized section. Such variations at boundary may cause uneven wear leading to geometry irregularities on the original smooth surface under certain conditions.
KOU Junyu
,
WANG Hengyu
,
ZHAO Xin
,
ZHAO Guotang
,
JIN Xuesong
. Influence of Rail Decarburization Layer on Wheel-rail Transient Rolling Contact Behavior[J]. Journal of Mechanical Engineering, 2018
, 54(4)
: 101
-108
.
DOI: 10.3901/JME.2018.04.101
[1] 陆钟武. 火焰炉[M]. 北京:冶金工业出版社, 1995. LU Zhongwu. Flame furnace[M]. Beijing:Metallurgy Industry Press, 1995.
[2] 黄灿. 重轨钢的脱碳研究[D]. 武汉:武汉科技大学, 2004. HUANG Can. Research on decarburization of heavy rail steel[D]. Wuhan:Wuhan University of Science and Technology, 2004.
[3] CLAYTON P, DANKS D. Effect of interlamellar spacing on the wear resistance of eutectoid steels under rolling-sliding conditions[J]. Wear, 1990, 135(2):369-389.
[4] CARROLL R I, BEYNON J H, Decarburisation and rolling contact fatigue of a rail steel[J]. Wear, 2006, 260:523-537.
[5] ROTTHÄUSER N, MUDERS L, GROHMANN H D. Influence of surface decarburisation area of the rail on rolling contact fatigue (in German)[J]. Eisenbahningenieur, 2001, 52:62-65.
[6] BOULANGER D. Rail metallurgical developments to address the changing needs of railway[C]//Proceedings of the World Congress on Railway Research, UK, Suffolk, Beccles:WCRR, 2003:932-939.
[7] ZHAO Xiangji, GUO Jun, WANG Hengyu, et al. Effects of decarburization on the wear resistance and damage mechanisms of rail steels subject to contact fatigue[J]. Wear, 2016, 364-365:130-143.
[8] KAPOOR A, FLETCHER D I, FRANKLIN F J. The role of wear in enhancing rail life[C]//Proceedings of the 29th Leeds-Lyon Symposium on Tribology, 2003:331-340.
[9] WANG Wenjian, GUO Jun, LIU Qiyue, et al. Study on relationship between oblique fatigue crack and rail wear in curve track and prevention[J]. Wear, 2009, 267:540-544.
[10] 赵鑫, 温泽峰, 王衡禹, 等. 三维高速轮轨瞬态滚动接触有限元模型及其应用[J]. 机械工程学报, 2013, 49(18):1-7. ZHAO Xin, WEN Zefeng, WANG Hengyu, et al. A 3-D transient finite element model for high-speed wheel-rail in rolling contact and its application[J]. Chinese Journal of Mechanical Engineering, 2013, 49(18):1-7.
[11] ZHAO Xin, LI Zhili. The solution of frictional wheel-rail rolling contact with a 3-D transient finite element model:Validation and error analysis[J]. Wear, 2011, 271:444-452.
[12] ESVELD C. Modern railway track[M]. 2nd ed. Delft:MRT-Production, 2001.
[13] CLARK R A, SCOTT G A, POOLE W. Short wave corrugations-an explanation based on stick-slip vibrations[J]. Applied Mechanics Rail Transportation Symposium, 1988, 96:141-148.
[14] 沈志云. 轮轨磨损的动力学预测及减少轮轨磨损的措施[J]. 铁道学报, 1992, 14(2):64-70. SHEN Zhiyun. Dynamic prediction of wheel-rail wear and measures to reduce wheel-rail wear[J]. Journal of Railway, 1992, 14(2):64-70.
[15] ZHAO Xin, LI Zili. A three-dimensional finite element solution of frictional wheel-rail rolling contact in elasto-plasticity[J]. Journal of Engineering Tribology, 2015, 229(1):86-100.
[16] 刘启跃, 王文建. 含碳量对车轮材料磨损影响的试验研究[J]. 润滑与密封, 2005(5):11-13. LIU Qiyue, WANG Wenjian. Experimental research on the impact of carbon content on wear of wheel materials[J]. Lubrication Engineering, 2005(5):11-13.
