裂纹

This paper presents an investigation into the detection of incipient fatigue cracks in a gearbox.

研究了齿轮箱早期疲劳裂纹的检测方法。

The micro-indentation results show that both theories for finite and infinitesimal deformation agree well with experimental data by suitably chosen material lengths. The results for fracture show that the difference between finite and infinitesimal deformation only exists in the vicinity very close to crack tip.

结果显示通过改变材料常数大变形和小变形都可以和微压痕实验结果吻合好，大小变形理论在断裂问题上的区别仅仅存在于非常靠近裂纹尖端处。

This paper discusses the reason of failure in gray cast iron ingot mould under thermal cycling condition from temperature field, thermal stresses ,the change process of coefficient of crack sensitivity,graphite oxidization and growth of cast iron in high temperature in the process of using ingot mould.

从钢锭模使用过程中的温度场、热应力、裂纹敏感系数的变化过程以及石墨氧化、高温下铸铁生长等角度对灰铸铁钢锭模在热循环条件下的失效原因进行了探讨。

The results of predicted crack initial lifetime under experimental condition are verified by the experimental data.

热循环条件下的裂纹初始化寿命模拟预测结果与实验数据近似。

The research achievement are acquired as follows: 1From mathematical models for inverse scattering in two dimensional homogenous media including Dirichlet, Neumann, Robin,all kinds of probable mixed boundaries and cracks, direct and inverse scattering are discussed, and ill-posed integral equation and indicator function method are formulated for the diverse of boundary identification. It is shown that the kernel of the integral equation characters the boundary of scatterer, which is determined by solving it by virtual of regularity method, meanwhile, some numerical tests are given.

本研究取得了如下研究成果： 1）在二维均匀介质逆散射各种边界识别的数学模型（包括Dirichlet，Neumann，Robin，各种可能的混合边界问题，裂纹问题）下，分别考虑了正散射问题和逆散射问题，推导了上述各种边界识别的不适定积分方程以及指示函数方法，由于积分方程的核充分表征了散射物的边界，由此说明只要利用正则化方法求解该积分方程，就可以确定散射物的边界，并给出了一些数值实验。

Meanwhile, the conservation of integral is proved strictly. Under the linear elastic situation, the relation of integral and stress intensity factor KI is derived.

通过I型裂纹的应用，由导出之的结果与应力强度因子手册解符合得较好，同时给出了积分偏斜应变能释放率的物理解释。

The intergranular crack s found in transition zone were also analyzed and some advices were put forward.

结果表明，两起事故都是由叶片激光熔覆层中缺陷引起的疲劳断裂，同时还分析了过渡区附近的沿晶裂纹产生原因，并提出了一些建议。

Results show that the sulfur content of steel and support segments are main factors leading to the intermedium cracks.

结果表明，钢中的硫和铸坯的支撑段是影响中间裂纹的主要因素。

Experiment scheme has been designed for the test of composite material character gating and acquire the four critical values of strain invariants in strain invariant failure theory which are the basic data for finite analysis.

在有限元建模过程中，采用了非层合单元SOLID45，保证了铺层取向；在加载策略上，以单元的失效来控制载荷变化的加载方式，实现了通过载荷增量的动态变化来控制每一载荷步下失效的单元数量，形成较好的裂纹扩展路线，避免了在线性加载条件下构件的连锁破坏。

A new method is proposed for determining the stress intensity factors bymeans of the curve lengths S measured from the isochromatic fringe loops nearthe crack tip.

本文提出一种测定裂纹尖端等色条纹环曲线长S确定应力强度因子的新方法。

Singer Leona Lewis and former Led Zeppelin guitarist Jimmy Page emerged as the bus transformed into a grass-covered carnival float, and the pair combined for a rendition of "Whole Lotta Love".

歌手leona刘易斯和前率领的飞艇的吉他手吉米页出现巴士转化为基层所涵盖的嘉年华花车，和一双合并为一移交&整个lotta爱&。

This is Kate, and that's Erin.

这是凯特，那个是爱朗。