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1.
Polymer Injection Forming (PIF) and Polymer Injection-Compression Forming (PICF) are new manufacturing technologies for sheet metal-polymer macro-composites, which result from the combination of injection moulding and sheet metal forming. In these processes, a metal blank is formed inside an injection mould by using the pressure of the molten polymer that, after cooling, permanently bonds to the metal sheet creating a fully finished product in only one production step. This paper presents a calibrated multi-physics numerical model of the processes that proves to be suitable to investigate the mutual metal-polymer interactions and to provide a reliable tool in designing the process as well as its control. 相似文献
2.
介绍了用有限元方法计算半导体方块电阻四探针测试中二维点电流势场的模型并且证明了其正确性。由于有限元方法对边界没有限制,该方法为方块电阻测试中精确确定边界修正系数,更重要的是为微样品测试结构确定提供直接明了的理论依据。 相似文献
3.
Isothermal Gas Forming of Mg Alloy AZ31 Sheet 总被引:1,自引:0,他引:1
There have been reports on sheet forming of Mg alloy in industry via the punch and die method;this paper is probably the first formal one for studying the sheet formability of AZ31 employing pressurized gas to press the sheet into a female die cavity at various elevated temperatures.The results indicate it is feasible to form a rectangular box via pressurized gas from extruded sheets of 0.5 and 1.7 mm thick.The formed box has 1:2 depth over width ratio,which should be large enough when dealing with realistic industrial sheet forming parts.Presently,forming a sheet of 0.5 mm thick is considered a technical challenge by industry,and it is conquered as demonstrated in this paper.Gas forming technique applied to Mg alloy is unprecedented and shows potential for industrial utilization. 相似文献
4.
文章对国内外开展微区薄层电阻测试的方法进行了综述,特别对改进范德堡四探针技术方法的测试原理、测试过程与测试结果进行了论述与分析,对微区电阻测试方法的进一步发展提出了一种可操作的方法,并研制出新型四探针测试样机。 相似文献
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6.
由于悬空侧壁部分的变形状态是圆锥形零件成形的关键,而径向拉应力是实现悬空部分成形的必要条件,同时也是该部分冲压成形成败的关键为此,经力学分析得出了侧壁部分径向拉应力的解析式和造成圆锥形零件破裂的最大径向拉应力的计算式。同时分析了圆锥形零件的成形载荷。 相似文献
7.
A variable friction model that relates the parameters of sheet metal drawing to the local lubrication conditions taking place during the deformation, has been integrated to a finite element program. Variable friction coefficients for the contacting surfaces are determined from the friction model, which uses the related parameters obtained at each time step of the finite element program as inputs. A number of numerical runs have been performed and the strains are compared with the experimental results for circular blanks. A good agreement is obtained between the numerical and experimental results for the variable friction model used. 相似文献
8.
本文描述用离子束透过钽金属膜进行混合和快速热处理方法来形成钽的硅化物.用溅射方法在P型硅衬底上淀积一层金属钽,然后用砷离子束透过钽金属模进行混合,采用快速热处理后形成了平整的硅化钽薄层.使用厚度为500埃的钽金属膜,得到钽的硅化物薄层电阻为5.5Ω/□.研究了砷离子能量、剂量及钽膜厚度对钽的硅化物薄层电阻的影响.用透射电镜和台阶仪对所形成的硅化钽进行了分析和厚度测量. 相似文献
9.
The flexural and shear rigidity of pultruded composite sheet pile panels consisting of E-glass fiber-reinforced polyester are studied in this paper. The analysis consists of an experimental investigation and an analytical modeling to determine the resistance of the sheet pile panels to the deflections for design of composite sheet pile walls. Timoshenko’s beam theory was used to experimentally determine the flexural rigidity (EI) and shear rigidity (kAG) of the panel. Three- and four-point bending tests were performed on six different span lengths and the results were self-compared from the two independent tests. Analytical expressions for the flexural and shear rigidities were derived to allow the prediction based on the layered structure of pultruded shapes. The values computed from the analytical expressions were examined with the experimental results. 相似文献
10.