Strain and temperature dependences in anisotropic constitutive equations for metal plasticity

个人计算机控制的组合式压力试验机研制于1991年。为了研究金属在高温下的各向异性弹粘塑性行为，设计并研制了与该试验机相连接的电炉和温度控制器。设计开发了带水冷器的轴扭复合加载杆。这些设备的开发费用由这笔赠款支持。试样外径和量规长度的变化以及扭转变形传递到炉外。由于测量外径的仪器是固定在炉壁上的，所以试样表面的铁砧会滑动。通过数据处理，消除了滑移引起的噪声。直径的变化是用薄板上的应变片来检测的。轴扭复合变形测量装置必须安装在试件上，不受试件变形的约束。但对于薄壁试样，通常的凸度是不够的。为解决这一问题，采用光滑试样，并设计了一种连杆称重装置。在设计的测量装置中，轴向和扭转变形由差动变压器分离检测。四套变压器及连接电缆和支架的费用由这笔赠款资助。这些变压器的多位移计是另一项支出。但由于经费不足，所设计的仪器无法研制。针对本课题，开发了双线性塑性应变路径的室温实验及后续屈服面测定软件。此外，在1992年11月召开的JSME关西分会会议上，提出了用桁架晶格模型表达应变历史相关弹塑性本构关系的研究。1993年研究了一种超塑性材料变形行为的应变速率和温度依赖关系。结果将在不久的将来公布。少

Personal computer controlled combined stress testing machine was developed in 1991. For investigation into anisotropic elastic-viscoplastic behavior of metals at high temperature, an electric furnace attachable to this testing machine and temperature controller were designed and developed. Rods for combined axial and torsional loading with water-cooler were also designed and developed. The expense for developments of these apparata was supported by this grant. The change in outer diameter and gauge length and torsional deformation of specimen are transmitted to outside of the furnace. Since the apparatus for measuring outer diameter is fixed to the wall of furnace, anvils slip on the surface of the specimen. The noise caused by slip is smoothed out by data processing. The change in diameter is detected by strain gauges on thin plates. The measuring apparatus for combined axial and torsional deformation must be attached to specimen without constraint to the deformation of the specimen. … More But usual protrusion is not adequate for thin-walled specimen. To cope with this problem, smooth specimen was adopted and a device with link and weight was designed. In the designed measuring apparatus, the axial and torsional deformation is separated and detected by differential transformer. The expense for four sets of transformer and connecting cable and braket was supported by this grant. The multi-displacement meter for these transformers was an another outlay. But the designed apparatus could not be developed because of shortage of expense.Relating to this project, a software for room temperature experiments of bilinear plastic strain path and determination of subsequent yield surface was developed. Furthermore, a study on expression of strain history dependent elastic-plastic constitutive relation with a truss lattice model was presented at JSME Kansai branch meeting held on Nov.1992. Strain-rate and temperature dependency of the deformation behavior of a superplastic material was investigated in 1993. Results will be presented in near future. Less