排序方式: 共有84条查询结果,搜索用时 15 毫秒
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为改善Mo-Cu合金组织结构和性能,采用分子自组装方法在Mo粉表面沉积一定量的纳米Cu,然后和一定比例的Cu粉混合,经液相烧结后制备出Mo-30Cu合金。通过与传统粉末冶金方法制备的Mo-Cu的组织性能进行了比较,对该合金的致密度、热导率和热膨胀系数等性能进行研究。结果表明,在Mo粉表面沉积的纳米级的Cu能显著提高Mo-30Cu合金的物理性能,改善组织结构,降低致密化烧结温度。 相似文献
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Effect of carbide formers on microstructure and thermal conductivity of diamond-Cu composites for heat sink materials 总被引:3,自引:0,他引:3
Diamond-copper composites were prepared by powder metallurgy, in which the diamond particles were pre-coated by magnetic sputtering with copper alloy containing a small amount of carbide forming elements (including B, Cr, Ti, and Si). The influence of the carbide forming element additives on the microstructure and thermal conductivity of diamond composites was investigated. It is found that the composites fabricated with Cu-0.5B coated diamond particles has a relatively higher density and its thermal conductivity approaches 300 W/(m·K). Addition of 0.5%B improves the interfacial bonding and decreases thermal boundary resistance between diamond and Cu, while addition of 1%Cr makes the interfacial layer break away from diamond surface. The actual interfacial thermal conductivity of the composites with Cu-0.5B alloy coated on diamond is much higher than that of the Cu-1Cr layer, which suggests that the intrinsic thermal conductivity of the interfacial layer is an important factor for improving the thermal conductivity of the diamond composites. 相似文献
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通过Gleeble-1500热模拟试验机进行铸态V-5Cr-5Ti合金的高温压缩和拉伸试验,研究压缩过程中变形温度对合金临界变形量和临界变形抗力的影响和在拉伸过程中变形温度对合金屈服强度和断面收缩率的影响规律,并用金相显微镜分析了合金的压缩变形组织。结果表明:V-5Cr-5Ti合金的热加工变形抗力大、塑性低,欲改善其加工性能,加热温度的选择及控制尤为重要。合金的加工温度应严格控制在1150~1250℃,变形量控制在30%以内,才能得到满足要求的合金。 相似文献
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在Gleeble1500热模拟材料试验机上对铸态V-5Cr-5Ti合金进行恒定应变速率热压缩模拟实验。研究了在1100~1250℃温度范围、应变速率为10.s-1和应变量分别为20%,30%,40%和50%条件下,铸态合金热压缩过程中的变形规律和热压缩后宏观形貌与组织的变化。通过分析不同压缩工艺条件下合金的应力-应变曲线和热压缩变形后的宏观形貌与微观组织,确定V-5Cr-5Ti合金的热压缩变形温度和变形量,进而制定出合金合理的锻造工艺,并通过生产实践验证了该锻造工艺。结果表明:V-5Cr-5Ti合金热锻造温度在1150~1250℃范围内,变形量控制在30%以内,可以得到性能满足需要的合金材料。 相似文献
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