典型聚酯涂层镀锌钢板的受热痕迹特征研究

Heated trace features of galvanized steel plate coated with polyester

为研究聚酯涂层镀锌钢板高温受热后的痕迹特征变化,选择热塑性丙烯酸涂覆的镀锌钢板为研究对象,在对其涂层进行热重分析的基础上,讨论钢板在不同受热温度及时间作用下的痕迹特征。结果表明:温度升高至360℃时,热塑性丙烯酸涂层发生明显的热解炭化,带涂层钢板的质量降低;在410~590℃温度范围内,涂层开裂、脱落,聚酯涂层钢板整体质量进一步降低;受热温度继续升高至600℃,镀锌层露出并发生氧化破坏后,钢板基体露出并发生氧化,钢板质量回升,局部区域不同程度的氧化过程导致整块钢板呈现出多层次且不均匀的受热痕迹;受热时间对痕迹的影响在高温下更为显著。

In order to study heated trace features of polyester coated galvanized steel sheet,thermoplastic acrylic coated galvanized steel sheet was selected as research object,and features of its heated trace under different temperature and duration was discussed based on thermogravimetric analysis of its coating. The results show that the coating obviously undergoes pyrolysis carbonization when temperature rises to 360 ℃,resulting in mass loss of steel. With cracking and shedding of the coating at temperature between 410 ℃and 590 ℃,steel mass further decreases. As galvanized layer exposes and oxidizes at 600 ℃,steel plate is exposed and oxidized,resulting in recovery of mass,and multi-layer and non-uniform heating traces are presented for the whole plate caused by oxidization of its parts at different degree. Comparatively,influence of heating duration on traces is more significant at higher temperature.