权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Surface modification of heat-resistive materials for gas turbines and basic analyzes by laser spectroscopy

燃气轮机耐热材料的表面改性及激光光谱基础分析

基本信息

批准号：
07455432
负责人：
ARAI Norio
金额：
$ 0.64万
依托单位：
Nagoya University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1996
项目状态：
已结题

项目摘要

In this research project have been carried out : experimental evaluation of degradation characteristics of C/C composite materials at high temperatures in methane-air combustion field, improvement of heat resitivity with SiC/glass double layr coating by pac cementation, and analysis of material degradation by in-situ observation using a high speed video camera.1. The following conclusion was given from the experimental studies on the improvement of heat resistirity of C/C composite materials with SiC/glass double layr coating by pack cementation, and optimization of glass layr material for crack-seal.(1) Heat resistivity was significantly improved by adding B_4C into the glass layr, at temperatures below 1573K.(2) The addition of B_4C was not effective at 1773K.However, such a silicide as ZrSi_2 or HfSi_2 improved the heat resistivity.(3) The addition of Al_2O_3 into the glass layr resulted in notable decrease of the heat resistivity.2. In-situ observation of the degradation of C/C composite materials in a premixed plane flame of acetylene with air was made, measuring images of Oh, CH and C_2 band spectra by a high speed spectra video camera (consisting of a monochramator and a high speed video camera), and the followings were concluded.(1) The two-dimensional images of OH and C_2 gave the in-situ information a bout the degradation of the C/C composite surface.(2) The addition of water into the flame increased the degradation of the surface.In summary, it was shown that the addition of ZrSi_2 or HfSi_2 into the glass layr was very effective for the improvement of the heat resistivity of the coated C/C composite materials, and that attacking by OH radicals resulting from H_2O was the main cause of the surface degradation.

本研究项目开展了：C/C复合材料在甲烷-空气燃烧场高温下的降解特性实验评价，SiC/玻璃双层涂层pac胶结提高热敏性，高速摄像机现场观察材料降解分析。通过对SiC/玻璃双层涂层充填胶结提高C/C复合材料耐热性的实验研究，以及玻璃层封缝材料的优化，得出以下结论。(1)当温度低于1573K时，在玻璃层中加入B_4C可显著提高玻璃的耐热性。(2)在1773K时添加B_4C无效。然而，ZrSi_2或HfSi_2等硅化物提高了耐热性。(3)在玻璃层中加入Al_2O_3后，其耐热性显著降低。通过对C/C复合材料在乙炔与空气的预混平面火焰中降解的现场观察，利用高速光谱摄像机（由一台单色仪和一台高速摄像机组成）测量了Oh、CH和C_2波段的光谱图像，得出了以下结论：(1) OH和C_2的二维图像提供了C/C复合材料表面降解的现场信息。(2)火焰中水的加入增加了表面的降解。综上所述，在玻璃层中加入ZrSi_2或HfSi_2对涂层C/C复合材料的耐热性改善非常有效，h2o产生的OH自由基的攻击是导致表面降解的主要原因。