作者：孙一宁^1,2, 王飞龙^1,2, 孙志斌¹, 于强¹, 翟光杰¹

作者单位：1. 中国科学院复杂航天系统电子信息技术重点实验室 中国科学院国家空间科学中心, 北京 100190;
2. 中国科学院大学, 北京 100049

关键词：热膨胀系数;无容器方法;图像处理;热物性测量

摘要：

传统接触测量的方法无法对高温范围金属材料的热膨胀系数进行测量,结合静电悬浮无容器技术和图像测量方法,通过半导体激光器加热悬浮样品,在加热的过程中利用CCD采集悬浮样品的图像,采用方向梯度算法提取图像中样品的边缘,并利用球谐函数拟合样品的体积,计算得到材料在不同温度下的热膨胀系数。采用纯锆的金属材料样品进行实验,在750~1800℃的温度范围内,测量得到固态样品锆的热膨胀系数随温度变化的表达式,验证该测量方法的有效性和准确度。

Research on measurement of thermal expansion coefficient by electrostatic levitation containerless method

SUN Yi'ning^1,2, WANG Feilong^1,2, SUN Zhibin¹, YU Qiang¹, ZHAI Guangjie¹

1. Key Laboratory of Electronics and Information Technology for Space Systems, National Space Science Center, Chinese Academy of Sciences, Beijing 100190, China;
2. University of Chinese Academy of Sciences, Beijing 100049, China

Abstract: Traditional contact measurement methods are difficult for the measurement of thermal expansion coefficient of metal metals at high temperature. By combining with the electrostatic levitation containerless technique and the image measuring method, the thermal expansion coefficient of the material at different temperatures can be calculated and obtained by using a semiconductor laser to heat the levitation sample, using CCD to collect the images of levitation samples in the heating process, using the orientation gradient algorithm to extract the edges of samples in the images, and using the spherical harmonics to perform function fitting of the sample volume. Experiment is conducted by using metal material sample with pure zirconium, measurement is conducted in the temperature range of 750-1800℃ to get the expression that the thermal expansion coefficient of solid sample zirconium changes along with the temperature, and the validity and precision of the measuring method are verified.

Keywords: thermal expansion coefficient;containerless method;image processing;thermophysical properties measurement

2016, 42(6): 1-4  收稿日期: 2016-02-20;收到修改稿日期: 2016-03-18

基金项目: 国家国际科技合作专项(2011DFA10440);中国科学院重大科研装备研制项目(YZ200928);中国科学院空间科学战略性先导科技专项(XDA04073500)

作者简介: 孙一宁(1992-),女,辽宁盘锦市人,硕士研究生,专业方向为无容器材料试验装置和热物性测量。

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