数点法与灰度阈值法在聚合物水泥水化程度定量分析中的应用

Application of point-counting and gray-threshold methods in quantitatively calculating the hydration degree of polymer-modified cement

本文介绍了背散射电子图像分析技术的两种定量数据处理方法:数点法与灰度阈值法。并对两种方法在聚合物改性水泥浆体水化程度分析中的适应性进行了研究。对比两种方法得到的结果,得到如下结论:若图像的质量不佳,可采用数点法进行分析,但需要增加图像数量以把误差降至最低;灰度阈值法可在图像数量较少时得到较精准的结果,但需要高质量的背散射电子图像以保证结果的准确性。为减小误差,数点法在进行统计之前应试验确定合适的网格点数;而除定量计算面积分数与体积分数外,灰度阈值法还可对颗粒形态、粒径分布等进行分析,是一个更全面的分析方法。本质上数点法与灰度法是同样的方法,在掌握了一定规律之后两种方法都是可靠的数据处理方法,在具体应用中应熟练掌握并扬长避短。

Two methods for quantitatively calculating the data based on backscattered electron image analysis(BSE-IA),graythresholdand point-counting,are introduced in this paper.The volume of non-hydrated cement particles in polymer-modified cement paste are analyzed by the two methods respectively.By comparing of the results obtained by the two methods,the following conclusions could be made:Point-counting method should be adopted when flawed samples and images are ineluctability,but more BSE images were needed to lower the errors to minimum.While,gray-threshold method can obtain accurate results when the number of images is small,but high quality BSE images without nick and defect is an indispensable must-have to ensure the accuracy of the results.gray-threshold method is a more comprehensive method,which can also be used for analyze the particle morphology,size distribution and so on,while the Point-counting method may cause errors if the number of grid points is inappropriate.The two methods are in essence the same and both are reliable data processing methods,researchers should know how to choose the proper method to make the best of the advantages and avoid the weaknesses.