We have developed two processing methods for creating fully 3D interconnected NiTi porous structures with arrayed micro-channels. Processing with HIPing results in a fully densified matrix, though bonding at powder boundaries is limited by oxidation. The strength of the powder bonding can be increased by processing with liquid phase sintering, though the resulting matrix is not fully densified. Tailored to the specific application, both of these methods are valuable for creation of these 3D interconnected structures. The stress-strain response of these types of samples was examined through digital image correlation. The full strain field around a single and multiple pores was examined and compared to continuum modeling of the same geometry. While the transformation is captured qualitatively as it initiates below the pores and propagates 45 to the applied tensile load, continuum modeling is unable to capture the discrete with multiple pores, as the transformation bands cross and interact during deformation. Therefore while continuum modeling will clearly illustrate the trends of the deformation, as pore size and spacing approaches the granular length scale, these discrete effects cannot be captured by continuum modeling but must be examined experimentally.

关键词：形状记忆合金；相变；多孔金属；粉末冶金；镍钛合金

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One weak aspect of synthetic polymer materials compared with steel and other metals is that these materials are combustible under certain conditions. Thus, the majority of polymer-containing end products must pass some type of regulatory test to assure public safety from fire. The main objective of this research is to apply combined effects of a catalyst in a clay-based polymer nanocomposite to enhance formation of char from a resin to form a protective layer consisting of char enhanced clay network during burning.

关键词：钢铁；高分子；碳化；可燃性；复合材料

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The study revealed that no single combination of Johnson-Cook model parameters provides superior overall prediction of penetration depth over the other possible combinations across the full range of rod L/D considered. The study provides valuable guidance on the selection of material model parameters future studies of kinetic energy penetration.

关键词：钢铁；铠装钢；钨合金；积木式分析；人因工程学

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