高温和超高温极端环境下陶瓷管材弹性模量评价新技术

本文综述了从室温到2200°C范围内陶瓷材料弹性模量的传统测试方法和新技术。针对脆性陶瓷管材在高温及超高温下弹性模量的评价难题,我们提出一种结合相对法和缺口环法的新方法,即相对缺口环法。通过比较缺口环与刚性圆块的横梁位移得到缺口环在高温及超高温下的真实变形量计算出精确的弹性模量。对典型的石英玻璃管、氧化铝陶瓷管、C/SiC/ZrB_2复合陶瓷管以及石墨管进行测试所得到的结果表明相对缺口环法准确有效,为高温及超高温等极端环境下脆性管材的结构安全提供了一种简便可靠的评价方法。

New Evaluation Methods for Determining the Elastic Modulus of Ceramic Tubes at High and Ultrahigh Temperatures

The conventional testing methods and some new evaluation methods for determining the elastic modulus of ceramics are summarized in this paper. Aimed at evaluating the elastic modulus of inorganic brittle tube materials at high and ultrahigh temperatures, we proposed a novelmethod that combined the split ring method with relative method, viz. relative split ring method. In this method, the displacements of the split ring and a rigid disk were compared to directly obtain the true deformation of the split ring at high and ultrahigh temperatures, thereby calculating the accurate elastic modulus. The relative split ring method has been utilized to evaluate several brittle tubematerials, such as quartz tube, alumina ceramic tube, C/SiC/ZrB₂ composite ceramic tube and graphite tube. The results indicate that this novel method is precise and effective, which provides a convenient and reliable approach for structural and safe evaluation of brittle tube materials in the extreme environment of high and ultrahigh temperature.