3种钢材在东海初期腐蚀速率的空间变异分析

为了研究X80、EH36和45#钢在东海海域42个站位的初期腐蚀速率.通过动电位极化曲线法获取出海实测的X80、45#和EH36钢2019年9月在东海42个站位的初期腐蚀速率数据,并以地统计学方法对数据进行分析,探索研究区内3种钢材初期腐蚀速率的空间分布及其变异特征,绘制初期腐蚀速率预测图.对于每一种钢材初期腐蚀速率的空间分布,45#钢在西南部高,东北部低;EH36钢在东北部高,西南部低;而X80钢靠近长江口海域低,其他海域高.X80、45#、EH36钢在东海的平均初期腐蚀速率分别为0.42、0.49、0.17 mm/a,并且3种钢材在东海初期腐蚀速率分布的空间变异特征明显,空间自相关性强,X80、45#、EH36钢的块金值分别为0.0148、0.0044、0.0017,变程为1000～2000 km.

Analysis of the Spatial Variability of the Initial Corrosion Rate of Three Steel in the East China Sea

To study the initial corrosion rate of X80, EH36 and 45# steel at 42 stations in the East China Sea, in this paper, the initial corrosion rate of X80, 45# and EH36 steel measured in the East China Sea in September 2019 were obtained by the potential polarization curve method. The data was analyzed by geostatistics to explore the spatial distribution and variation characteristics of the initial corrosion rate of the three steels in the study area, and draw the initial corrosion rate prediction map. The spatial distribution characteristics of the initial corrosion rate of each type of steel are as follows:the spatial distribution of the initial corrosion rate of 45# steel is higher in the southwest and lower in the northeast; the spatial distribution of the initial corrosion rate of EH36 steel is higher in the northeast, lower in the southwest; while the spatial distribution of the initial corrosion rate of X80 steel is obviously lower in the seas close to the Yangtze River estuary, and higher in other seas. The distribution of the initial corrosion rate of the three steels presents different characteristics. At the same time, statistical analysis shows that the average initial corrosion rate of the three steels in the East China Sea is 0.42 mm/a for X80, 0.49 mm/a for 45#, and 0.17 mm/a for EH36. In addition, the spatial variability of the initial corrosion rate distribution of the three steels in the East China Sea is obvious, and the spatial autocorrelation is strong. The nugget values of X80, 45# and EH36 are 0.0148, 0.0044, and 0.0017, respectively, and the range is between 1000~2000 km.