Fracture Mechanics Approach into the Crack Growth Behavior in Ceramics under Ball-on-Plate Rolling Contact

Surface crack growth behavior of a Si-D23-D2N-D24-D2 plate from small pre-indentations located in the contact center was investigated under ball-on-plate contact.近表面压力是由汉森的分析解决方案计算的。裂缝生长行为在计算压力的条件下和压力强度因素两者都在滚动接触和滑动-包括-滚动接触下进行了讨论。Crack Driving Forces Under Bull-on-Plate ContactThe Crack Were Observed to Grow Only in a Direction Perpendicular to the ball的运动。The maximum value of KイD2IイエD2， KイD2ImaxイエD2， was found to remain constant during the crack growth。压力强度因子范围， △ KI-D2 II型D2和△ KI-D2 III型D2，在另一只手上，在裂缝长度两者下增加在滚动接触下和在滑动-包括滚动接触下增加。所有的压力强度因素都是由摩擦力加剧的。It was found that the crack growth is（由K-D2 Imax）D2 combined with K-D2 II K-D2和K-D2 III K-D2。It was also found that the crack growth is promoted by the increased K-D2Imax K-D2，K-D2 II K-D2 and K-D2 III K-D2 by the friction force under sliding-including-rolling contact. 2。Crack Growth Behavior under Shear StressIt was found that the crack was grew by the shear stress under sphere Herzian contact， whereas Kyy D2I Kyy D2II Kyy D2 and Kyy D2III Kyie D2 were superimposed with the phase shifted。“裂缝传播测试”在剪切压力下通过使用弯曲扭矩测试机器的使用而产生。It was found that the cracks were propagated by the lower D2 II D2 than that caused by the sphere Hertzian contact.因此，它被包括在一种与赫兹接触下的裂缝传播的模式II。

Surface crack growth behavior of a SiィイD23ィエD2NィイD24ィエD2 plate from small pre-indentations located in the contact center was investigated under ball-on-plate contact. Near surface stresses under the spherical Hertzian contact were calculated by the Hanson's analytical solution. The crack growth behavior was discussed in terms of the calculated stresses and the stress intensity factors both under rolling contact and under sliding-including-rolling contact.1. Crack Driving Forces under Ball-on-Plate ContactThe cracks were observed to grow only in a direction perpendicular to the motion of the ball. The maximum value of KィイD2IィエD2, KィイD2ImaxィエD2, was found to remain constant during the crack growth. The stress intensity factor ranges, △KィイD2IIィエD2 and △KィイD2IIIィエD2, on the other hand, increase with the increase in crack length both under rolling contact and under sliding-including-rolling contact. All the stress intensity factors were increased by the friction force. It was found that the crack growth is controlled by KィイD2ImaxィエD2 combined with △KィイD2IIィエD2and △KィイD2IIIィエD2. It was also found that the crack growth is promoted by the increased KィイD2ImaxィエD2, △KィイD2IIィエD2and △KィイD2IIIィエD2 by the friction force under sliding-including-rolling contact.2. Crack Growth Behavior under Shear StressIt was found that the crack was grew by the shear stress under spherical Herzian contact, whereas KィイD2IィエD2KィイD2IIィエD2 and KィイD2IIIィエD2 were superimposed with the phase shifted. The crack propagation tests under shear stress were carried out with the use of a bending-torsion testing machine. It was found that the cracks were propagated by the lower △KィイD2IIィエD2 than that caused by the spherical Hertzian contact. Therefore, it was concluded that the crack propagated in mode II under spherical Hertzian contact.