裂纹

From different point of view,the chaotical phenomenen induced by double period bifurcation is found.In this paper, the dynamical model of bearing-elastical rotor with a cross-section of crack is estabilished.

以轴中间存在弓形裂纹的Jeffcon弹性转子为研究对象，考虑转轴涡动对裂纹开闭规律的影响，建立了轴承—弹性裂纹转子的非线性动力学模型。

Near threshold fatigue crack growth tests were conducted under torsion on circumferentially pre--cracked round bars of a stainless steel.

研究了带环状预裂纹不锈钢圆棒试样在循环扭转载荷下、门槛值附近的疲劳裂纹扩展行为，用应力强度因子表征了裂纹扩展开始的门槛值。

Low cycle fatigue crack propagation tests were conducted on a circumferentially pre--cracked round bar of a stainless steel under various combinations of cyclic torsion and tension.

研究了从SUS316NG不锈钢圆棒试样的环状预裂纹开始的低周疲劳裂纹扩展行为，分析了扭转/拉伸复合加载时不同载荷比对弹塑性疲劳裂纹扩展的影响。

When heat load flux increases to 3MW/m2, there are microcracks on surface in several micrometers depth.Microcracks complect to a reticulation along the tungsten grain boundaries.

热流密度为3MW/m2时，表面无宏观裂纹，试样表层几个微米内出现微裂纹，微裂纹沿钨晶粒边界交织成网状分布。

With the invariableness of friction coefficient between cracks, the coalescence mode of crack propagation is decided by the geometry location between cracks.

扩展裂纹最终以何种形式连接、贯通，在裂纹间摩擦系数不变情况下，则主要取决于裂纹之间的几何位置。

The nanocrack is a crack in nano size withingrain and it may cause transcrystalline fracture.

纳米级裂纹是晶粒中纳米大小的裂纹，它可能是导致穿晶断裂的裂纹。

The general feature of the plastic deformation is similar in both charging or uncharging hydrogen specimens.

发现：氢的存在并不改变在Ⅰ型或混合型载荷作用下，裂纹尖端的塑性变形特征，即在主裂纹前端，应变呈不对称分布，裂纹尖端Schmid因子决定了条带状局部形变带的轴线方向。

The wavelet time-frequency properties of the uncracked rotor and the cracked rotor were discussed by the continuous wavelet time-frequency analysis algorithm. A new algorithm using the wavelet time-frequency analysis algorithm to detect the crack was proposed. The influence of the sampling frequency on the wavelet time-frequency analysis algorithm was analyzed through the numerical simulation research; the valid sampling frequency was presented.

利用连续小波时频分析方法，讨论了裂纹转子与无裂纹转子的小波时频特性，提出了利用小波时频分析方法识别裂纹的新方法；数值仿真研究了采样频率对小波时频分析方法的准确性和有效性的影响，并给出了建议性的采样频率。

It turns out that crack closure is the main reason for retardation, and crack tip blunting, crack deflection and strain-induced martensite would reinforce it.

室温蠕变对裂纹扩展产生延滞的原因主要是裂纹闭合，同时裂尖钝化、裂纹偏折及形变诱发马氏体的形成也会起到一定的作用。

When sending an even electric current down the plate vertical to the crack line, the electric current was detoured near the crack tips for the existing of cracks and Joule heats was produced. The instantaneous high temperature formed the point heat source.

在通入垂直于裂纹的均匀电流作用下，由于裂纹的存在，裂纹尖端出现绕流现象，产生焦耳热，瞬时高温形成点热源。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。