排序方式: 共有83条查询结果,搜索用时 15 毫秒
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对聚甲基丙烯酰亚胺(PMI)泡沫碳环氧复合材料夹层结构进行了平拉、平压、侧压、弯曲、剪切等性能试验,并对试样破坏模式进行了分析.结果表明:泡沫夹层结构平拉、平压、剪切性能取决于芯材的性能,表现为芯材的破坏,弯剪试样更能表征泡沫的剪切性能,泡沫夹层结构具有优越的侧压和弯曲性能,碳面板( 1.05 mm)/泡沫(30 mm)夹层结构侧压强度为26.5MPa、模量为5.88 GPa,弯曲刚度为3.05 kN·m2、模量为97.5 GPa. 相似文献
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司玉锋%孟丽华%陈玉勇 《宇航材料工艺》2006,36(3):10-13,25
着重介绍了Ti2AlNb基合金的成分、显微组织及性能,综述了合金元素及热处理工艺对Ti2Al-Nb基合金组织性能的影响,介绍了Ti2AlNb基合金熔炼凝固特性,并展望Ti2AlNb基合金的未来。 相似文献
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姚旺%张宇民%韩杰才 《宇航材料工艺》2006,36(3):41-46
预测了反应烧结SiC(RBSiC)的物理及部分力学性能与游离Si含量的变化关系,并对预测值与测量值进行比较以验证其符合程度。经预测,随Si含量的增加,RBSiC的密度呈线性下降,尤其是气孔对材料密度的影响非常明显;线膨胀系数和热导率均应呈加速上升趋势,比热容稍有下降;各模量均有下降趋势。随着气孔的增加,RBSiC的膨胀量变化不明显,比热容和热导率均呈减速下降趋势。RBSiC测量值与预测值产生偏差是因为材料中Si含量的增加导致缺陷增多以及计算性能用数据有偏差所致,但预测仍能较符合RBSiC性能随Si含量变化趋势,因此认为预测值较为合理可作为性能参考值使用。 相似文献
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土地利用效益不高,长期以来一直制约着农民收入的增长。《物权法》的颁布,对提高土地的效益将会起着重大的促进作用。本文探讨了在《物权法》的实施过程中,我们应当注意的一些具体问题。 相似文献
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Experiments in materials science on the ground and in reduced gravity using electrostatic levitators
Paul-Franois Paradis Takehiko Ishikawa Shinichi Yoda 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(12):2118-2125
To counter residual accelerations, dedicated levitators or positioners are necessary to support a host of materials science experiments on the ground and in microgravity. All levitators (e.g., aerodynamic, acoustic, electromagnetic, electrostatic, optical) have their own merits and limitations but the electrostatic scheme offers the combined advantages of processing millimeter-size objects, independent heating, quasi-spherical shape of molten materials, handling of materials under extreme temperatures for hours, virtually convection-free samples, and wide view around the samples for diagnostic. These attributes provide unique research opportunities in materials science on the ground as well as under reduced gravity. In particular, electrostatic levitators are very attractive to measure the physical and structural properties of equilibrium and non-equilibrium liquids, to synthesize multi-function materials, and to understand metastable phase formation, vitrification, and diffusion. In this paper, research and development carried out by the Japan Aerospace Exploration Agency over the years in the field of electrostatic levitation are summarized and the main results obtained in materials science are presented. 相似文献
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超轻型Mg—Li合金 总被引:12,自引:0,他引:12
Mg-Li合金具有高的比强度和比模量,在航天及航空等领域中具有广阔的发展前景。本文详细介绍了Mg-Li合金的发展现状及性能改善的途径。 相似文献
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