不同测试方法下高温应变片热输出分析  

Analysis of thermal output of high temperature strain gauge by different measurement methods

作　　者：刘梓才[1] 喻丹萍[1] 李锡华[1] 卢琰琰[1] 陈学徳 李朋洲[1] 

机构地区：[1]中国核动力研究设计院,成都610041

出　　处：《核技术》2013年第4期186-189,共4页Nuclear Techniques

摘　　要：用以夹代焊为热输出的测试方法,揭示对高温应变片热输出的影响。通过分析热输出的影响因素,对高温应变片在安装试件材料和基底材料线膨胀系数不匹配情况下的热输出测试进行了探索。对悬空、夹持、点焊等各种测试方式下的热输出进行了分析比较,利用各种测试方式的特点得到了各种热输出。结果表明:悬空方式下的热输出可以作为高温应变片安装于基底材料上的热输出,为温度变化速率区别于出厂标定温度条件时热输出曲线的获得提供了依据。夹持方式下的热输出可以作为点焊热输出的替代,实现了以夹代焊,节约了成本,而且实现了逐片标定。悬空和夹持方式下热输出的比较揭示了安装试件材料不匹配时不采用实际安装时的热输出曲线会引起较大的误差。在各种热输出测试方法中,夹持方式可以替代点焊方式,实现热输出的逐片标定,并具有较好的热输出准确性。Background： Thermal output of high temperature strain gauges can be measured by different methods. Purpose： This paper is to discover measurement methods＇ effects on thermal output of high temperature strain gauge and to suggest a method of clamping instead of welding for fixture of high temperature strain gauge for thermal output measurement. Methods： By analysis of impacting factors of thermal output, thermal outputs were explored for mismatching thermal expansion coefficients between material of components to be tested and that of strain gauge base. Thermal outputs of all kinds by different fixture methods were obtained and compared for hanging, clamping and spot welding, respectively. Results： Thermal output obtained by way of hanging strain gauge can be used in case of installation on material of the same thermal expansion coefficient as the strain gauge base. And this hanging measurement method provides access to thermal output that strain gauge undergoes different temperature changing ratio from that one of provision offered by strain gauge fabrication factory. Thermal output obtained by way of clamping measurement method can substitute for the one obtained by spot welding. This clamping measurement method can not only realize the effect of spot welding, reducing calibration cost due to spot welding of strain gauges, but also realize the aim of calibration of strain gauges one by one with the strain gauges be intact after calibration. Differences between thermal outputs by two measurement ways of both hanging and clamping explain that large divergence can be made when thermal expansion coefficients between the material of strain gauge base and the one of the component to be installed on. Conclusions： Thermal output can be measured among all methods by fixture of clamping instead of welding, with an advantage of realizing strain gauge calibration one by one and also with a high precision.

关 键 词：高温应变片 热输出 测试方法 夹持 

分 类 号：O602[理学—化学]