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101.
Coline Beal Xavier Kleber Damien Fabregue Mohamed Bouzekri 《Scripta materialia》2012,66(12):1030-1033
The susceptibility of a Fe22Mn0.6C twinning-induced plasticity steel to liquid zinc embrittlement has been investigated by performing hot tensile tests on bare and electrogalvanized specimens using a Gleeble thermomechanical simulator. Tensile tests were carried out at different temperatures and strain rates. The studied steel can be severely embrittled by liquid zinc (drastic reductions in elongation at rupture and fracture strength) given particular conditions of temperature and strain rate. 相似文献
102.
中美工程机械租赁市场对比分析 总被引:1,自引:0,他引:1
目前,中国工程机械租赁企业可以按照国营、私营分类,也可以分为专业租赁企业和施工企业开展对外租赁业务两种。但是,因为行业中仍以小型个体企业为主,所以行业大小很难准确描述。但是,行业总量无疑是很大的。 相似文献
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During injection molding, it is not uncommon for shear heating to cause localized temperatures exceeding 300°C. This heating, if not suppressed, can cause vinyl degradation. Three main factors influence shear heating. They are (a) mold design, especially restrictions such as small gates; (b) injection conditions, especially injection velocity; and (c) compound viscosity. To address the compound factor, two new vinyl compounds have been created for custom injection molding, which are especially designed to suppress the shear heating temperatures. Geon® M3700 has good impact at room temperature, and Geon® M3800 has outstanding impact at room temperature and at low temperatures. These compounds use a new technology that produces a balance of properties never before achievable. These innovative compounds show enhanced processability including improved static thermal stability, improved shear stability, tolerance of higher injection screw rpms, tolerance of higher injection speeds, the ability to mold at lower injection pressures, reduced molding cycles, and the ability to fill thin part walls. Also designed into the compounds are improved color fastness during exposure to light, improved appearance, and reduced corrosiveness. Other properties such as impact strength, tensile strength, modulus, heat deflection temperature, hardness, UL flammability rating, specific gravity, and mold shrinkage remain comparable to older technology. 相似文献
110.
This paper presents a generalized approach to the full-wave analysis of multilayer microstrip structures. One of the structures studied is a new kind of microstrip bandpass filter realized in a double-layer dielectric substrate configuration. This filter demonstrates the use of the third (vertical) dimension in the design of microstrip devices. The approach involves the mixed potential integral equation technique, the Method of Moments, and an S-parameter extraction technique based on a simple form of Matched Load Simulation. Simulated and measured results for various microstrip structures are presented and show good agreement. The approach is demonstrated in detail for 2-port structures, with an outline of how it can readily be extended to the n-port case 相似文献