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原位合成TiC颗粒强化铝合金组织与性能 总被引:2,自引:0,他引:2
采用铝系合金2A14(LD10)作为母合金,利用原位合成法制备了TiC颗粒弥散强化铝基材料。显微组织观察表明,合金中的TiC颗粒呈等轴状,尺寸约为1~3μm。加入TiC颗粒后,合金铸态组织显著细化,室温抗拉强度和屈服强度得到一定程度提高,但塑性下降。150℃时,合金的拉伸性能变化随TiC加入量增加而变化的规律与室温相似。合金中TiC颗粒的引人大大提高了合金的耐磨性能。在油润滑条件下,TiC/2A14材料的耐磨损体积远远优于其母合金以及其他典型的金属耐磨材料,如耐磨黄铜、ZA30锌基合金和Al—30Si高硅铝合金。 相似文献
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新型英语精读教学探微 总被引:2,自引:0,他引:2
朱丽骏 《中国民航飞行学院学报》2008,19(4):46-48
从大学英语教学观念、教学内容和教学手段等方面着手,探讨了大学英语精读存在的问题,同时提出相应的对策,以期达到大学英语教学整体优化的目的。 相似文献
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针对航空发动机试验工厂的业务特点进行了CAPP系统的设计开发,设计了结构化工艺和非结构化工艺两种基本模式的工艺管理方法,并实现了CAPP系统与ERP系统的集成。 相似文献
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To cope with the problems that edge detection operators are liable to make the detected edges too blurry for synthetic aperture radar (SAR) images, an edge detection method for detecting river in SAR images is pro- posed based on eontourlet modulus maxima and improved mathematical morphology. The SAR image is firstly transformed to a contourlet domain. According to the directional information and gradient information of direction- al subband of contourlet transform, the modulus maximum and the improved mathematical morphology are used to detect high frequency and low frequency sub-image edges, respectively. Subsequently, the edges of river in SAR image are obtained after fusing the high frequency sub-image and the low frequency sub image. Experimental re sults demonstrate that the proposed edge detection method can obtain more accurate edge location and reduce false edges, compared with the Canny method, the method based on wavelet and Canny, the method based on contourlet modulus maxima, and the method based on improved (ROEWA). The obtained river edges are complete and clear. 相似文献
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