(1. 苏州有色金属加工研究院, 苏州 215026;
2. Unité de Thermique et d'Analyse Physique, Laboratoire d'Energétique et d'Optique, Université de Reims, BP 1039, 51687 Reims Cedex 2, France)
摘 要: 通过喷丸处理方法在纯钛表面形成一定厚度的超细晶组织(纳米及亚微米组织), 利用扫描热显微镜(SThM)对超细晶组织的热性能进行分析。 在实验基础上建立理论模型。 根据从SThM扫描探针针尖传输到试样各种组织中的热流变化, 分析材料的热导率与组织的变化关系。 结果表明, 超细晶组织的热导率与具有较大晶粒的基体相比有明显的降低, 其原因主要与细晶组织中导电电子浓度的降低、 晶格缺陷密度的增加及电子与声子在该类组织中的强烈散射有关。
关键字: 钛; 喷丸处理; 超细晶组织; 热导率
(1. Suzhou Institute for Nonferrous Metals Processing Technology,
Suzhou 215026, China;
2. Unité de Thermique et d'Analyse Physique, Laboratoire d'Energétique et d'Optique, Université de Reims, BP 1039, 51687 Reims Cedex 2, France)
Abstract: Scanning thermal microscopy (SThM) was used to analyze thermal properties of an ultrafine-grained titanium surface layer produced by ultrasonic shot peening. A theoretical approach, based on this experiment, was used to calculate the heat flow from the probe tip to the various microstructures in the sample. The results show that the thermal conductivity of the nanostructured surface layer decreases obviously compared with that of the coarse-grained matrix of the sample. This is mainly due to the decrease of electron concentration and strongly scattering of electrons and phonons in the ultrafine-grained structures.
Key words: titanium; ultrasonic shot peening treatment; ultrafine-grained microstructures; thermal conductivity