纳米钨在高压下的物理力学行为与尺寸效应研究  

Physico-Mechanical Behavior and Size Effect of Nano-Tungsten under High Pressure

作　　者：赵康林 王齐明[1] 张友君 蒋刚[1] 彭放[1] 李延春[2] ZHAO Kanglin;WANG Qiming;ZHANG Youjun;JIANG Gang;PENG Fang;LI Yanchun(Institute of Atomic and Molecular Physics,Sichuan University,Chengdu 610065,Sichuan,China;Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]四川大学原子与分子物理研究所,四川成都610065 [2]中国科学院高能物理研究所,北京100049

出　　处：《高压物理学报》2024年第3期29-36,共8页Chinese Journal of High Pressure Physics

基　　金：国家自然科学基金(12074273);四川大学实验技术立项(SCU221022)。

摘　　要：探究尺寸效应对材料高压物性的影响规律有助于开发具有新颖或者改良特性的新材料。采用金刚石对顶砧结合同步辐射X射线衍射技术,研究了平均晶粒尺寸分别为30和65 nm的多晶钨粉在高压下的静态压缩行为。通过分析每个压力点下X射线衍射图谱的峰位和半高宽等,得到了纳米金属钨在高压下的晶胞体积、晶粒尺寸和微观应变等。通过拟合三阶Birch-Murnaghan方程,得到了30和65 nm钨的体弹模量,分别为257(7)GPa和343(8)GPa。结合前人的研究结果发现,当晶粒尺寸从微米降低至10 nm,钨的屈服强度逐渐增大,10 nm钨的屈服强度较微米晶样品的屈服强度提高了3.5倍;体弹模量呈现先增大后减小的趋势,30 nm钨的体弹模量较65 nm钨减小了25%。Exploring the influence of size effect on the physical properties of materials under high pressure is helpful for the development of new materials with novel or improved properties.The static compression behaviors of polycrystalline tungsten powder with average grain sizes of 30 and 65 nm under high pressure were studied by using diamond anvil cell(DAC)combined with synchrotron radiation X-ray diffraction respectively.By analyzing the peak position and the half-height width of the X-ray diffraction spectrum at each pressure,the unit cell volume,grain size,and microscopic strain of nano-tungsten metal under high pressure were obtained.By fitting the third Birch-Murnaghan equation,the bulk moduli of 30 and 65 nm tungsten are obtained to be 257(7)GPa and 343(8)GPa,respectively.Combined with the results of previous studies,it is found that when the gain size decreases from micron to 10 nm,the yield strength of tungsten at 10 nm increases by 3.5 times compared with that of microcrystal samples;the bulk modulus shows a tendency of increasing firstly and then decreasing,and the bulk elastic modulus of tungsten at 30 nm decreases by 25% compared with that of tungsten at 65 nm.

关 键 词：状态方程 屈服强度 体弹模量 高压 纳米晶体 

分 类 号：O521.2[理学—高压高温物理]