高温硫化(HTV)硅橡胶凭其强憎水性、憎水迁移性和恢复性等优越性能,成为合成绝缘子外绝缘的首选材料。然而,与无机材料相比,高温硫化硅橡胶更易受环境影响而老化,因此通过氙灯辐照对高温硫化硅橡胶进行紫外加速老化试验。采用静态接触...高温硫化(HTV)硅橡胶凭其强憎水性、憎水迁移性和恢复性等优越性能,成为合成绝缘子外绝缘的首选材料。然而,与无机材料相比,高温硫化硅橡胶更易受环境影响而老化,因此通过氙灯辐照对高温硫化硅橡胶进行紫外加速老化试验。采用静态接触角法测量和评价硅橡胶材料的憎水性,同时进行了硬度以及扫描电子显微镜(SEM)测试,另外采用image-pro plus 6.0软件对SEM图片进行测试分析。试验结果表明:短时氙灯辐照对高温硫化硅橡胶表面憎水性影响不大,材料硬度有变大趋势,材料表面凹凸不平,粗糙度变大,并有填充物外露的趋势。随着辐照时间增加,欲析出颗粒数目逐渐增多,颗粒大小逐渐变大,总面积增加。展开更多
随着中国"西电东送"及特高压输电工程的展开,复合绝缘子厂家纷纷研制出适合特高压输电工程线路应用的特高压等级的复合绝缘材料。笔者针对哈密至郑州±800 k V特高压直流输电工程在哈密段的复合绝缘子老化问题,提取哈密...随着中国"西电东送"及特高压输电工程的展开,复合绝缘子厂家纷纷研制出适合特高压输电工程线路应用的特高压等级的复合绝缘材料。笔者针对哈密至郑州±800 k V特高压直流输电工程在哈密段的复合绝缘子老化问题,提取哈密地区干燥强紫外辐射的气候特征,在干燥环境下对特高压等级的复合绝缘材料和普通电压等级的复合绝缘材料进行紫外加速老化实验。对实验样品进行静态接触角测试,硬度测试,傅里叶变换红外光谱(FTIR)分析。实验结果表明:两种试样硬度均变大,憎水性均部分丧失,并有填充物外露;红外光谱中Si-CH3键和Si-O-Si键的峰面积均减小;在两种试样初始数据相近的情况下,特高压等级样品各个数据的变化量均小于普通等级样品。展开更多
Ultraviolet （UV） aging is one of the main factors which cause premature damage of asphalt pavements in the Tibetan Plateau, China. According to the measured levels of UV radiation, aging tests of styrene-butadiene r...Ultraviolet （UV） aging is one of the main factors which cause premature damage of asphalt pavements in the Tibetan Plateau, China. According to the measured levels of UV radiation, aging tests of styrene-butadiene rubber （SBR） asphalts with different contents of three anti-UV-aging agents including nano-TiO2, CeO2 and carbon black are performed. Common indices, which include retained penetration after thin film oven tests （TFOT） and softening point, and strategic highway research program （SHRP） indices of aged asphalts are evaluated. Infrared absorption spectral analysis is performed on asphalt specimens with 0. 8% carbon black which have been aged for different aging times （500, 1000 and 1 500 h）. By grey incidence analysis, the optimal contents of anti-UV-aging agents are determined. The results show that TiO2 and CeO2 are not only good UV absorbing or shielding agents, but also strong oxidants. Carbon black is a good anti-UV-aging agent, and its optimal content is about 0. 8% of asphalt weight. UV aging of asphalt mainly occurs in the early stages of aging. The longer the aging time, the more severe the aging of asphalt.展开更多
文摘高温硫化(HTV)硅橡胶凭其强憎水性、憎水迁移性和恢复性等优越性能,成为合成绝缘子外绝缘的首选材料。然而,与无机材料相比,高温硫化硅橡胶更易受环境影响而老化,因此通过氙灯辐照对高温硫化硅橡胶进行紫外加速老化试验。采用静态接触角法测量和评价硅橡胶材料的憎水性,同时进行了硬度以及扫描电子显微镜(SEM)测试,另外采用image-pro plus 6.0软件对SEM图片进行测试分析。试验结果表明:短时氙灯辐照对高温硫化硅橡胶表面憎水性影响不大,材料硬度有变大趋势,材料表面凹凸不平,粗糙度变大,并有填充物外露的趋势。随着辐照时间增加,欲析出颗粒数目逐渐增多,颗粒大小逐渐变大,总面积增加。
文摘随着中国"西电东送"及特高压输电工程的展开,复合绝缘子厂家纷纷研制出适合特高压输电工程线路应用的特高压等级的复合绝缘材料。笔者针对哈密至郑州±800 k V特高压直流输电工程在哈密段的复合绝缘子老化问题,提取哈密地区干燥强紫外辐射的气候特征,在干燥环境下对特高压等级的复合绝缘材料和普通电压等级的复合绝缘材料进行紫外加速老化实验。对实验样品进行静态接触角测试,硬度测试,傅里叶变换红外光谱(FTIR)分析。实验结果表明:两种试样硬度均变大,憎水性均部分丧失,并有填充物外露;红外光谱中Si-CH3键和Si-O-Si键的峰面积均减小;在两种试样初始数据相近的情况下,特高压等级样品各个数据的变化量均小于普通等级样品。
文摘Ultraviolet （UV） aging is one of the main factors which cause premature damage of asphalt pavements in the Tibetan Plateau, China. According to the measured levels of UV radiation, aging tests of styrene-butadiene rubber （SBR） asphalts with different contents of three anti-UV-aging agents including nano-TiO2, CeO2 and carbon black are performed. Common indices, which include retained penetration after thin film oven tests （TFOT） and softening point, and strategic highway research program （SHRP） indices of aged asphalts are evaluated. Infrared absorption spectral analysis is performed on asphalt specimens with 0. 8% carbon black which have been aged for different aging times （500, 1000 and 1 500 h）. By grey incidence analysis, the optimal contents of anti-UV-aging agents are determined. The results show that TiO2 and CeO2 are not only good UV absorbing or shielding agents, but also strong oxidants. Carbon black is a good anti-UV-aging agent, and its optimal content is about 0. 8% of asphalt weight. UV aging of asphalt mainly occurs in the early stages of aging. The longer the aging time, the more severe the aging of asphalt.
