拉伸应变

In the course of FEM model building, tensile test experiment is taken to work out the real stress-strain curve. Ring compress test is also done in this paper, through which the friction coefficient is worked out and the friction mechanism and relevant friction model for tube stagger spinning is studied. The experiments ensured the veracity and reliability of the FEM modeling.

建模过程中，通过材料拉伸试验测定了旋压材料00Ni12Cr5Mo4TiAlV时效钢的真实应力应变曲线；利用圆环镦粗试验测定了材料在不同润滑状态下的摩擦系数，并对强力旋压的摩擦性质和摩擦模型的选择进行了研究，确保了建模关键参数的准确性和可靠性。

FLD is remarkabaly affected by the strain paths,which brings the inconvenience to industry.And the forming limit stress diagram which established with limit stress is independent on the strain paths and it is more convenient and practical to use as the criterion of forming limit under complex strain paths.

为确定板材拉伸失稳的成形极限，人们从理论和实验等方面提出了许多研究与评价方法，其中最有现实意义和应用最为广泛的是20世纪60年代由Keeler[1]和Goodwin[2]提出的以极限应变构成的成形极限图(forming limit diagram，FLD)的概念。

Effects of heating speed and strain rate on tensile strength of 30CrMnSi.

升温率和应变率对30CrMnSi拉伸强度的影响。

Through analyzing error, it was shown the feasibility and the reliability of solving the new relationship of stress and strain by ordinary tensile curve.

通过对误差的分析，说明由一般的拉伸曲线求解该新型应力应变关系的可行性及可靠性。

The results show that the dynamic tensile strength of marble is heightened with increasing strain rate.

结果表明，大理岩的动态拉伸强度随着应变率的提高而增加。

Based on the WM-model, the various stages of SPIF process was studied and the forming characters have been realized. Based on the SM-model of the truncated cone, the blank thickness element was sub-meshed into three levels. And through the forming simulation of the process, access to the plate stress and strain of the different regions in forming, and proposed the establishment of a sub-regional mechanism to explain the incremental forming, that is, in different regions, sheet deformation is different. In the main region which reflects the major character of SPIF, the deformation pattern is the composition of bending and extrusion.

基于完整有限元分析模型对渐进成形过程的各阶段进行分析，从而全面认识渐进成形的特点；基于方锥台件局部有限元分析模型，并将板材厚度方向的单元细分为三层，通过成形过程仿真，获取成形中，板材不同区域的应力、应变情况，提出并建立分区域的渐进成形机理解释，即，在不同区域，板材的变形方式是不同的，其中，对体现渐进成形主要特点的方锥台件和圆锥台件的侧壁充分变形区域，其变形方式是拉伸-弯曲复合变形。

The results show that twinning could make great contribution to the deformation at room temperature.

主要考察拉伸和压缩变形中孪晶的微观特征，晶粒尺寸和织构对于孪生变形的影响，并从定量上计算孪生对于应变的贡献。

But it is difficult to make certain proper reference state in the uniaxial tensile test ,and there has not been an acceptable formula to express its stress-strain relationship.

在对SIS的单轴拉伸测试中，很难确定合适的参考状态，也没有一个被广泛认可的公式来表达其应力应变关系。

In terms of yield strength of pipes,it is proposed that yield strength ...

因此，在进行级别高于X80的管线钢拉伸试验时，建议使用Rp 0.2的值作为材料的屈服强度，或使用与Rp 0.2相对应的总应变强度作为屈服强度。

The results showed that:a Cyclic strtching at 500με,1000μεand 1500μεwith the frequency of 0.4Hz affected the physiological activity of osteoblasts delivered from rat calvaria.

应变分别为500με、1000με和1500με，频率为0.4Hz的周期性拉伸刺激影响大鼠颅盖骨中分离出的成骨细胞的生理活性。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。