According to the profile of brake disc crack macro-morphology, the main forms of long crack are approximately its own expansion and multiple cracks connectivity. Regarding the brake disk typical conditions during operation, the circumferential residual stress are considerable by calculated the thermal stress in 300 km/h emergency braking using the finite element method. Thereafter, the thermal fatigue crack growth of brake disc is drove through circumferential residual stress. Based on the conclusion, the brake disc grid with crack is established, and then the distribution of the stress intensity factor and the coupled propagation law between multi-cracks in the crack propagation process are researched. The results show that, the stress intensity factor of crack tip have regularity for different initial crack size and the crack shape tends to flatten with crack propagation under same load; When multiple crack are propagated, crack spacing smaller, the faster expansion and the interaction are more obvious; however, considering the structure and size limits, the more the number of cracks, the smaller the stress intensity factor when crack extended to critical value.
SHI Xiaoling
,
LI Qiang
,
SONG Zhanxun
,
YANG Guangxue
. Research on Coupled Extension Characteristic of Thermal Fatigue Cracks at Forged Brake Disc for High Speed Train[J]. Journal of Mechanical Engineering, 2016
, 52(10)
: 126
-132
.
DOI: 10.3901/JME.2016.10.126
[1] LE H,GARDIN C. Analytical prediction of crack propagation under thermal cyclic loading inducing a thermal gradient in the specimen thickness - comparison with experiments and numerical approach[J]. Engineering Fracture Mechanics,2011,78(4)：638-652.
[2] 王世杰,闫明,佟玲,等. 循环载荷下热疲劳裂纹的应力强度因子[J]. 机械工程学报,2010,46(10)：64-68.
WANG Shijie,YAN Ming,TONG Ling,et al. Stress intensity factor of thermal fatigue crack under cyclic loading[J]. Journal of Mechanical Engineering,2010,46(10)：64-68.
[3] 赵荣国,李红超,蒋永洲,等. 航空发动机涡轮盘用GH4133B合金疲劳裂纹萌生与短裂纹扩展研究[J]. 机械工程学报,2013,49(10)：116-126.
ZHAO Rongguo,LI Hongchao,JIANG Yongzhou,et al. Research on fatigue crack initiation and short crack propagation of GH4133B superalloy used in turbine disk of aero-engine[J]. Journal of Mechanical Engineering,2013,49(10)：116-126.
[4] 李继山,李和平,林祜亭. 高速列车制动盘裂纹现状调查分析[J]. 铁道机车车辆,2005,25(6)：3-5.
LI Jishan,LI Heping,LIN Huting. Crack investigation and analysis on the brake disc of high speed train[J]. Railway Locomotive and Car,2005,25(6)：3-5.
[5] BAGNOLI F,DOLCE F,BERNABEI M. Thermal fatigue cracks of fire fighting vehicles gray iron brake discs[J]. Engineering Failure Analysis,2009,16(1)：152-163.
[6] MORI H,TOMINAGA T,MATSUI M,et al. Observation of thermal cracks of microstructural size scale by thermal effect during wear in Ni-Cr-Mo alloy steel brake discs[J]. Journal of the Japan Institute of Metals,2006,70(10)：785-789.
[7] STARINK M,REED P. Thermal activation of fatigue crack growth：analyzing the mechanisms of fatigue crack propagation in superalloys[J]. Materials Science and Engineering,2008,491(1-2)：279-289.
[8] 闫明,王世杰,孙淑霞,等. 热疲劳裂纹网的屏蔽规律及主裂纹应力强度因子的计算方法[J]. 机械工程学报,2009,45(12)：279-283.
YAN Ming,WANG Shijie,SUN Shuxia,et al. Shielding effect rule of thermal fatigue crack net and calculating method of stress intensity factor of main crack[J]. Journal of Mechanical Engineering,2009,45(12)：279-283.
[9] 丁振宇,高增梁,王效贵. 16MnR钢过载峰作用下的疲劳裂纹扩展行为研究[J]. 机械工程学报,2013,49(16)：84-90.
DING Zhenyu,GAO Zengliang,WANG Xiaogui. Study on crack growth behavior of 16MnR subjected to single tensile overload[J]. Journal of Mechanical Engineering,2013,49(16)：84-90.
[10] YANG Zhiyong,HAN Jianming,LI Weijing,et al. Analyzing the mechanisms of fatigue crack initiation and propagation in CRH EMU brake discs[J]. Engineering Failure Analysis,2013,34(8)：121-128.
[11] XIAO X,YAN X. A numerical analysis for cracks emanating from a surface semispherical cavity in an infinite elastic body by FRANC3D[J]. Engineering Failure Analysis,2008,15(1-2)：188-192.
[12] 陈传尧. 疲劳与断裂[M]. 武汉：华中科技大学出版社,2003.
CHEN Chuanyao. Fatigue and fracture[M]. Wuhan：Huazhong University of Science and Technology Press,2003.
