门槛值

使用恒K（max）方法测试物理小裂纹门槛值研究

Study on physically small crack growth threshold testing using constant k_ ( max ) method

变质处理后断裂韧性（K1c）和疲劳裂纹扩展门槛值（△Kth）提高，冲击韧度（αk）提高1倍以上；耐磨性明显提高；

The fracture toughness ( K1c ) and threshold of fatigue crack growth (△ Kth ) are improved , the impact toughness (α k ) increased by above one times .

一种估算疲劳裂纹扩展门槛值△K（th）的新方法

A new method for predicting fatigue crack propagation threshold

理论门槛值的研究探讨了碳势、温度及Cr元素含量对碳化物极限值和碳势门槛值的影响。

The effect of carbon potential temperature and Cr content on CPT and CEV are studied .

载荷对测定4340钢在海水中条件门槛值△K（th）的影响

The influence of loading on conditional δ k_ ( th ) measured on 4340 steel in seawater

Fisher最优分割在桥梁健康监测门槛值分级中的应用

Application of Fisher optimal division to threshold values classification of bridge health monitoring

同时通过疲劳试验确定了母材、焊缝及热影响区的Paris表达式，并得到疲劳裂纹门槛值。

And the Paris formula of base metal , weld metal and HAZ are also given by fatigue experiment .

然而企业家人力资本的现状不容乐观，特别是对FDI溢出效应的检测，绝大部分省份都没有跨过门槛值。

However , the situation of entrepreneur human capital is not optimistic , especially for the detection of FDI spillovers .

湿H2S环境下典型压力容器用钢应力腐蚀开裂门槛值的估算

Estimation of Threshold Value for Stress Corrosion Cracking of Typical Steel for Pressure Vessel under Wet H_2S Environment

提出了非饱和黄土的初始损伤应力和应变门槛值的确定方法，并且定义了基于CT数的损伤变量。

The author has put forward how to decided initial damage stress and strain threshold value of the unsaturated loess and defined damage variable by CT 's number .

N2/Ar流量比超过某一门槛值时不能生成（Ti，Al）N；

But ( Ti , Al ) N film can not be developed as the N 2 / Ar flow ratio increases over a certain critical value .

本文对车轴钢材料的疲劳裂纹扩展速率da/dN和应力强度因子门槛值△K（th）的特性进行了试验和计算。

The behaviour of fatigue crack growth rate da / dN and threshold of stress strength factor △ K_ ( th ) in axle steel is investigated and calculated .

因此，在TA饱和的情况下，通过合理设定该时问差的门槛值，外部故障和任何内部故障均可做到明显的区分。

Therefore , this time difference can be utilized to identify the external fault from any internal fault in the case of TA saturation .

用当量J积分范围表征疲劳裂纹扩展速率不受试件结构形状和尺寸的影响，并且得到了裂纹扩展的门槛值和裂纹扩展寿命评价方程。

Shapes and sizes and that the relations between fatigue crack growing rates and equivalent J integral ranges were not affected by specimens . shapes and sizes .

疲劳裂纹扩展门槛值ΔKth的测定

Measurement of fatigue crack growth threshold △ kt

描述裂纹扩展规律使用较广泛的是Paris公式，但对于接近裂纹扩展门槛值的数据点已不再适合用Paris公式。

The Paris equation is widely used to describe crack propagation laws , but it is not appropriate to use it to describe data points near the crack propagation threshold value .

从CT细观试验结果出发，给出了应力损伤门槛值，将准静态岩石应力应变全过程曲线分为5个阶段，得到了岩石损伤演化的初步规律。

Based on the results of CT test on the meso-damage of rock , the stress threshold value of rock damage is given . For static link failure , the whole process curve is divided into five stages .

Pareto分布中门槛值的确定及其在股票市场中的应用将车门门槛横梁放在保险杆的前下方。

Determination of the Threshold Value in Pareto Distribution with Empirical Research in Stock Markets ; Place the sling crossbar under and forward of the bumper .

退火对非晶的影响有温度门槛值Tk的存在，随退火温度升高，非晶合金结构显非线性变化。

The effect of annealing temperature on the amorphous threshold Tk existence , with the annealing temperature , the amorphous alloy was non-linear change .

P50钢轨钢的奥氏体晶粒度对其门槛值和裂纹扩展速率的影响

Influence of Austenitic Grain Size of P50 Railway Steel on Threshold Value and Crack Growth Rate

揭示了一般流动表面模型的点和线的特征与景观生态学和保护生物学中的景观结构之间的关系，证实了生态过程动态与趋势中某些门槛值的存在以及应用这些门槛值定义SP的可能性。

It demonstrates the relationship between the spatial properties of a general surface model discussed in theoretical geography and the landscape representation model used in landscape ecology and conservation biology .

采用国家标准GB6398-86规定的试验方法，对15MnVNq钢焊接接头在疲劳裂纹扩展中速区和近门槛值区的裂纹扩展规律进行了深入的研究。

Using the test method prescribed in the GB6398 & 86 standard , we conduct a deepgoing study on the fatigue crack propagation law of welded joints of 15MnVN_q steel in the medium rate and threshold regions .

研究了7075铝合金、209O和2090＋Ce铝锂合金的疲劳门槛值、门槛值附近断口的分形维数及其断口形貌间的关系。

Abstract The relationship among fatigue threshold range , fractal dimension of fatigue surface near threshold area and fracture surface morphology for aluminium alloy 7075 , Al-Li alloys 2090 and 2090 + Ce was investigated .

利用有限元软件ANSYS，首次对单搭接胶接接头进行拓扑优化，结果表明：接头承载较大时门槛值k取0.2较为适宜，承载较小时取0.3较为适宜；

Finite element software ANSYS is applied to optimize the adhesively bonded single lap joint topologically for the first time . The results showed that the threshold values 0.2 and 0.3 are appropriate for joint under low load and large load respectively .

提出疲劳裂纹尖端塑性核半径门槛值Rth的概念及计算方法，Rth是材料性质。

In this paper , a concept for the radius of plastic core at the top of a fatigue crack is raised .

8090Al-Li合金疲劳短裂纹门槛值的研究

Threshold of short fatigue crack for 8090 Al-Li alloy

文章报告了两组Q235钢小缺口试件在平面应力与平面应变条件下的疲劳启裂门槛值的测定结果。

In this paper , the experimental results of fatigue initiation threshold at sharp notch are reported for two groups of Q 235 steel under plane stress and plane strain conditions .

结果表明，纯氮离子渗氮存在电压门槛值，只有在700V左右的高电压下，并且采用间歇供N2闭炉方式进行离子渗氮，才能产生明显的渗氮效果。

Experimental results show that there exists a voltage threshold in the ion nitriding with pure nitrogen . Only when the voltage is high as 700 V or so , the technique will produce obvious nitriding effect .

影响中国全要素生产率（TFP）的主要因素和中国对来源于不同国家技术溢出的吸收能力和有效性的差异分析。研究结果证明中国在吸收国外技术溢出中存在门槛值。

Through studying the spillover effect of manufacturing RD other departmental RD and foreign RD , we analysis the affection factor of China 's total factors productivity ( TFP ) and the absorbency of spillover from different country and the doorsill value of spillovers .

基于断裂力学原理，分别给出了此公式中材料裂纹扩展门槛值ΔKth，断裂韧性K1C和张开函数f的测定方法；

The approaches of determining the material ′ s fatigue crack growth threshold value Δ K_ ( th ), the fracture toughness K_C and the opening function f in this four-parameter curve were presented respectively by means of fracture mechanics principles .