纳米结构Cu固体材料的低温热容性能研究  

Thermal capacity of nanocrystalline copper at low temperatures

作　　者：张洪亮[1,2] 雷海乐[2] 唐永建[2] 罗江山[2] 李恺[2] 邓晓臣[1,2] 

机构地区：[1]西南科技大学材料科学与工程学院,绵阳621010 [2]中国工程物理研究院激光聚变研究中心,绵阳621900

出　　处：《物理学报》2010年第1期471-475,共5页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10804101)资助的课题~~

摘　　要：采用真空热压技术在高真空和温度为523K的情况下,通过不同压力将直径平均大约为45nm的Cu纳米粉末压制成纳米结构Cu固体材料,将X射线衍射、扫描电镜与物性测试仪(PPMS)相结合,研究了低温下纳米结构Cu固体材料的比热容随温度和材料密度的变化.研究结果表明:低温比热容随着纳米结构Cu固体材料密度的降低而升高;纳米结构Cu固体材料的低温比热容大于粗晶Cu,其增加率在10K左右达到极大.基于缺陷的热振动效应,探讨了这些现象的物理机理.Copper nanoparticles with average diameter of about 45 nm were compressed in a high-strength mold under different pressures at 523 K to produce nanocrystalline copper. The X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and physics-property-measurement system （PPMS） were used to study the thermal capacity of nanoerystalline Cu as a function of temperature and the mass density at low temperatures. The experimental results indicate that the thermal capacity at low temperatures increases with decreasing density. The thermal capacity of nanocrystalline Cu is higher than that of the coarsed Cu and the increase ratio reaches maximum at around 10 K. The physical mechanism of the phenomenon is explored in this paper.

关 键 词：纳米结构Cu固体材料 自悬浮定向流技术 缺陷 热容 

分 类 号：TB383.1[一般工业技术—材料科学与工程]