Development of a System for Measuring Thermal Diffusivity of Thin Films by Laser Flash Method Based on a New Principle.

基于新原理的激光闪光法测量薄膜热扩散率系统的开发。

• 批准号: 01850145
• 负责人: WASEDA Yoshio
• 金额: $ 2.82万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Developmental Scientific Research (B).
• 财政年份: 1989
• 资助国家: 日本
• 起止时间: 1989 至 1990
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-01850145/
• 关键词: Thermal Diffusivity; Thermal Conductivity; Lase-Flash Method; Molten Salts; Ferrites; High Temperature Melts; 光外線検出器

A laser flash method for measuring thermal diffusivity in the direction parallel or perpendicular to the sample surface of film has been developed. On measurement of parallel direction of a sample, a pulsed laser beam which has narrow line-shaped cross section is flashed onto the front surface of the sample. The temperature response at the back surface at a certain distance away fro the line-shaped illuminated area of a laser beam is measured by the infrared detector and the thermal diffusivity value can be dete mined by comparing measured temperature response curve with theoretical one. On the other hand, the measurement of thermal diffusivity in the direction perpendicular to the sample surface of a film, a pulsed laser beam whose diameter is about 10 mm, is flashed onto the front surface of the sample. The temperature response at the back surface is measured by the infrared detector. The thermal diffusivity value can be determined by comparing with the theoretical solution including … More a pulse duration. The usefulness the present method has been demonstrated by measuring successfully thermal diffusivities of metallic foil samples of platinum (25 mum copper (18 mum), SUS304 stainles s steel (50 mum) and nickel (130 mum).Ruby lasers usually employed in the laser flash method for measuring thermal diffusivity of various inorganic substances a known to have the inhomogeneous energy distribution and their particular spatial intensity structure significantly effects the quantitative accuracy of the resultant thermal diffusivity data in some cases. Random packed fiber bundle made of plastic optical fiber wi plastic optical guiding rod has been developed for homogenizing the energy distribution in a laser beam on the specimen surface. T usefulness of this new device has been well approved by measuring the energy distribution and the thermal diffusivity of nickel disc.A simple cell and easy data processing have been proposed for measuring the thermal diffusivity of a liquid sample at high temperatures using the laser flash method. A cell consists of a liquid sample sandwiched by two metallic plates. The front surface one metallic plate is exposed to a single pulse of beam laser and the resulting temperature rise of the back surface of the other metal plate is measured. The logarithmic analysis proposed by James using the initial time region of the temperature response curve of a two layered cell system has been extended to apply to the present three layered cell system in order to estimate the thermal diffusivity value of a liquid sample. Measurements of distilled water and methanol were made first and the results were found to be in good agreement with the reference data. Then, the thermal diffusivities of molten NaNO_3 at 593-660 K and of molten KNO_3 at 621-694 were determined and the results also appear to agree reasonably well with those reported in the literature. Less

开发了一种激光闪光法，用于测量平行或垂直于薄膜样品表面方向的热扩散率。在测量样品的平行方向时，将具有窄线形横截面的脉冲激光束照射到样品的前表面上。通过红外探测器测量距激光束线状照射区域一定距离处的背面温度响应，通过将测量的温度响应曲线与理论温度响应曲线进行比较，可以确定热扩散率值。另一方面，在垂直于薄膜样品表面的方向上测量热扩散率时，将直径约为10mm的脉冲激光束照射到样品的前表面上。背面的温度响应由红外探测器测量。热扩散率值可以通过与包括脉冲持续时间的理论解进行比较来确定。通过成功测量铂（25μm铜（18μm）、SUS304不锈钢（50μm）和镍（130μm）金属箔样品的热扩散率，已经证明了本方法的有效性。红宝石激光器通常用于激光闪光方法中，用于测量已知具有不均匀能量分布及其特殊特性的各种无机物质的热扩散率。 在某些情况下，空间强度结构会显着影响所得热扩散率数据的定量准确性。由塑料光纤和塑料光导杆制成的随机堆积光纤束已被开发用于均匀化样品表面上激光束的能量分布。通过测量镍盘的能量分布和热扩散率，这种新装置的实用性得到了充分认可。提出了一种简单的电池和易于数据处理的方案 用于使用激光闪光法测量高温液体样品的热扩散率。池由夹在两块金属板之间的液体样品组成。将一块金属板的前表面暴露于激光束的单脉冲，并测量另一块金属板的后表面所产生的温升。 James 提出的使用两层电池系统温度响应曲线的初始时间区域的对数分析为 扩展到适用于当前的三层电池系统，以估计液体样品的热扩散率值。首先对蒸馏水和甲醇进行了测量，发现结果与参考数据非常吻合。然后，测定了熔融NaNO_3在593-660 K和熔融KNO_3在621-694 K的热扩散率，结果似乎与文献中报道的结果相当吻合。 文学。少

项目成果

太田 弘道,柴田 浩幸,小倉 岳,早稲田 嘉夫,渋谷 幸生,布施 正樹: "ランダム配向光ファイバ-束によるルビ-レ-ザ-のエネルギ-分布の均一化および熱拡散率測定への応用" 熱物性. 3. 102-105 (1989)

Hiromichi Ota、Hiroyuki Shibata、Gaku Ogura、Yoshio Waseda、Yukio Shibuya、Masaki Fuse：“使用随机取向光纤束的红宝石激光器的均匀能量分布及其在热扩散率测量中的应用”热物理性质.3.102-105（1989）

H. Ohta, H. Shibata, Y. Shibuya and M. Fuse: "Random packed optical fiber bundle for homogenizing the energy distribution in a laser beam on the specimen surface and its application to the thermal diffusivity measurements." Netsu Bussei. Vol. 3. 102-106 (

H. Ohta、H. Shibata、Y. Shibuya 和 M. Fuse：“用于均匀化样品表面激光束能量分布的随机封装光纤束及其在热扩散率测量中的应用。”

H. Ohta, G. Ogura, Y. Waseda and M. Suzuki: "Thermal diffusivity measurements of molten salts using a three-layered cell by the laser flash method." Rev. Sci. Instrum. Vol. 61. 2645-2649 (1990)

H. Ohta、G. Ogura、Y. Waseda 和 M. Suzuki：“通过激光闪光法使用三层池测量熔盐的热扩散率。”

G. Ogura, In-Kook Suh, Hiohta and Y. Waseda: "Thermal diffusivity measurements of boron oxide melts by laser flash method." J. Ceram. Soc. Japan, Inter. Ed.Vol. 98. 320-322 (1990)

G. Ogura、In-Kook Suh、Hiohta 和 Y. Waseda：“通过激光闪光法测量氧化硼熔体的热扩散率。”

Gaku Ogura,InーKook Suh,Hiromichi Ohta,Yoshio Waseda: "Thermal diffusivity measurements of boron oxide melts by laser flash method" J.Ceram.Soc.Japan,Inter.Ed.98. 320-322 (1990)

Gaku Ogura、In-Kook Suh、Hiromichi Ohta、Yoshio Waseda：“通过激光闪光法测量氧化硼熔体的热扩散率”J.Ceram.Soc.Japan，Inter.Ed.98 (1990)。