查询词典 plastic deformation

According to the elastic-plastic theory, the calculation method of tangential stress , radial stress of expansion casing both in elastic deformation area and in plastic deformation area is deduced and the minimum critical load between expansion core and casing was determined.

根据弹塑性的理论，推导了膨胀套管在弹性变形区和塑性变形区的周向应力和径向应力计算模型，确定了膨胀套管膨胀时在膨胀芯头与套管之间所需的最小接触载荷。

The deformation mechanism is mainly the single-slip and cross-ship, the fracture mechanism is mainly the congregation of transgranular micro-hole, and large uniform deformation occurred before tough fracture, and therefore, the ability of plastic deformation and the mechanical properties of the material were remarkably improved. These fully indicate that the new melt-treatment developed in this work is an effective and advanced technique, and further testify that the improvement of metallurgical quality of the material is the key to enhance its mechanical properties, especially its plastic deformation performance. The results of tensile and compression tests at elevated temperature also indicate that the suitable hot-working temperature range is 400～450℃. 4. A steady-state plastic flow exists during the plastic deformation of the aluminum sheet used for pressure can at elevated temperature. A hyperbolic sine relationship can be satisfied between the steady-state flow stress and strain rate by introducing an Arrhenius term which involves some thermal activation parameters, i.

压力罐用铝材中的主要冶金缺陷为Al〓O〓夹杂物、气孔及富Fe杂质相；高效熔体处理显著改善了材料的冶金缺陷的存在形态，使含杂量明显减少、夹杂物尺寸变细小且分布均匀，富Fe杂质相变为细小、分布均匀的团球状或短棒状的复杂化合物，同时也明显细化了结晶组织；此外，由于高效熔体处理有效地减少了材料中裂纹萌生源数量，因而改变了材料的塑性变形微观过程及断裂方式，主要以单滑移和交滑移进行塑性变形，断裂方式为穿晶微孔聚集型，韧性断裂前产生了大量的均匀变形，不易出现变形失稳，从而显著提高了罐用铝材的塑变能力和力学性能。

The influence of indentor radius on the plastic deformation has been discussed and some important results are as follows:(1) The influence of the ratio of ceramic coating thickness to indentor radius on the failure of coating, plastic deformation of substrate and crack propagation are obvious.(2)The propagation of crack in ceramic coating is assumes to be of semi-elliptical shape under normal contact with a rigid sphere.(3)Fatigue life of ceramic coating is mainly decided by substrate and load, the lower substrate elastic moduli and load, the more cycles of fatigue.

分析了压头半径对塑性变形的影响，模拟结果表明；(1)陶瓷涂层厚度和压头半径之比对涂层失效、基体塑性变形及裂纹的形成有显著影响；(2)在刚性球压头静态挤压条件下，陶瓷涂层中的预制裂纹按照椭圆形裂纹规律扩展；(3)陶瓷涂层的疲劳寿命与基体和载荷有很大关系，基体弹性模量越小，疲劳寿命延长。

The planning of the processing parameter is based on the plastic deformation of the metal because the planning of the cold rolling technique is affected by the ability plastic deformation of the metal. Industrial PC is the master processor of the cold rolling machine. The process of cold rolling monitored by the corresponding functional component real-timely.

冷辗工艺的设计受金属塑性变形能力的影响，因此工艺参数设计以金属塑性变形为基础；冷辗机控制系统以工业PC为主控制器，通过相应的功能模块实现对冷辗进程的实时监控。

To establish the constitutive equation of material, the metric tensor for stress , strain and their transformation equations between different configurations are derived, and basic theory of finite deformation as well as elasto-plastic deformation criterion are studied. By analyzing the applicability of different element models, four-node quadrilateral degenerated Mindlin isoparametric element is adopted because of its good versatility, and the element stiffness matrix is derived. The static implicit elasto-plastic finite element equation for complex skin stretch-forming is put forward based on Updated Langrange formulation.

本文首先系统地阐述了有限变形的相关基本理论，针对板料成形建立了应力应变度量张量及其相应的转换关系；介绍了材料的屈服准则、塑性变形强化规律、塑性流动规律以及加、卸载准则，并在此基础上建立了有限变形各向异性弹塑性本构方程；对板料成形的单元模型进行了分析，针对飞机蒙皮零件特点，采用通用性强的四节点四边形退化Mindlin等参壳单元进行成形模拟，并导出其单元刚度矩阵的具体形式；基于以上研究，以逐级更新Langrange描述的持续虚功率原理为基础，建立了率形式的复杂蒙皮拉形过程静态隐式弹塑性有限元方程。

A continuum model was established by introducing Newton stress formula into the elastic-plastic model to describe the deformation behavior of material in bonding zone. Based on the model, the mechanism of plastic deformation and the influence of detonation velocity on plastic deformation were analyzed and compared with experiments.

该文引入牛顿应力公式到弹塑性模型，以近似描述结合区材料行为，建立了连续介质模型，对波状结合区的塑性变形及爆轰速度对塑性变形的影响进行计算分析，并与试验结果对比。

The severe plastic deformation on 1060pure aluminum at room temperature was carried outby accumulative roll-bonding, the microstructure evolution and mechanics performance change of 1060 industry pure aluminum before and after plastic deformation were studied.

采用累积叠轧焊方法在室温下对1060纯铝进行剧烈塑性变形，并分析1060纯铝变形前后内部微观组织结构的演变和力学性能的变化。

In the second part, the theory of numerical simulation is introduced, including description of body configuration, elastic-plastic large deformation constitutive equation and finite element formula. It is followed by the derivation of equation from the basic theory of elastic-plastic deformation. The solution to temperature field, thermal stress, thermal strain, equivalent effective stress and equivalent strain is achieved then. In addition, we exposit the relation between machine load and thermal load in coupling analysis.

介绍了物体的构形及其描述，弹塑性大变形的本构方程、有限元列式；并进一步论述了弹塑性变形的基本理论，推导了弹塑性方程组；阐述了温度场的求解、热应力及热应变的理论概要，说明了等效应力与等效应变，并进一步阐明了在热力耦合分析中，机械负荷与温度负荷之间的关系；此外，还简介了Marc AutoForge程序结构的特点。

ABSTRACT In order to study the thermally activated characteristics of plastic deformation and the effect of alloying element on the thermal activation of structural steels, the properties of plastic deformation for 20g and 13Ni3CrMoV steels have been examined in the temperature of 77—473K and strain rate of 〓. The experimental phenomena show that the effective stress of plastic deformation decreases with the increase of alloying elements content (namely solute solution softening) and the frequency factor deceases with the increase of effective stress.

本文以13Ni3CrMoV钢焊接结构的动态断裂破坏为背景，通过系统测试20g和13Ni3CrMoV钢的动态屈服特性，分析比较了结构钢的形变热激活特点，从频率因子〓随有效应力σ〓增大而下降和合金固溶软化的实验现象出发，在位错以弯折方式克服晶格Peierls位垒的基础上，提出了溶质原子与螺型位错热激活弯折相互作用的物理模型和σ〓-T分段线性关系的形变热激活理论假设，并借助计算机数值模拟，分析探讨了合金固溶软化的微观机制。

The forming process and the characteristics of plastic deformation, the sites of the heavily strained zones with severe thickness reduction and their evolution, the influences of the main processing parameters, such as the plastic melt pressure and its distribution from the gate to the end of the mold, and of friction coefficient between the sheet flange and the mold, on these during the hybrid forming of the aluminum sheet have been revealed by the updated Lagrange finite element formulation for the finite elastic-plastic deformation.

运用弹塑性大变形更新的Lagrange有限元方法，揭示了铝薄板的成形过程和塑性变形的特点与规律、大塑性变形区的产生位置及其塑性变形特点，探明了复合成型过程中塑料熔体压力及其分布规律以及铝薄板凸缘与模具摩擦系数等主要工艺参数对铝薄板成形过程和塑性变形的影响规律。

It goes back to what I told you...

现在回到我告诉过你的。。。

With a supporter in Mr Charest and an admirer in Mr Dumont, Mr Harper may be encouraged to call an election himself.

由于在沙雷那边有个支持者，杜蒙那边有个崇拜者，鼓励哈珀为自己举行一次选举。