Evaluating The Homogeneity Of Materials Quantitively Based On Digital Image Processing

The homogeneity of the material affects the physical properties, chemical properties,internal structure of the material, which has far-reaching significance of the materials about their long time using, persistent stability and the like.At the present,domestic and foreign scholars have studied the homogeneity of the material for many years,however,there was little researching findings,and the object of study were confined to one or two kinds of materials so that it can not be generalized to evaluating other material’s homogeneity quantitatively.In this paper,we will study and analyze the SEM,TEM image of the nano-coating of graphite electroless copper plating,by statistical analysis and image processing technology,the aim is to find applicable method to evaluate the homogeneity to more materials.The main work of this article:1、 Making image preprocessing to SEM,TEM image of the nano-coating of graphite electroless copper plating,and designing a localized OTSU binary method to the40nm graphite eiectroless copper plating.2、 Identifying connected domain of the target particles and marking to locate them, then calculating the relevant parameters of the binary image by image morphological processing.3、 Improving an existed method which is that selecting the coefficient of variation of "area ratio of particle " and "quantity of particles".These two indicators are used to evaluate homogeneity of material.4、 Designing a new method,that is first,making image processing which has been stated above to the image of materials,then letting the distance between the target particles be the indicators,analyzing the possible characteristics of different kinds of materials,third making cluster analysis,last,calculating the coefficient of variaton of within-class distance,the coefficient of distance among the classes and the average within-class distance,what’s more and deviation of the target rang of particle clustering on the whole image as homogeneity evaluated indicators to characterize the distribution of target particles on material cross-section.5、 Using these two methods to evaluate the homogeneity of SEM,TEM image of the nano-coating of graphite electroless copper plating in this paper,and the results are consistence with sensory analysis. 6、 Finally,these two methods are applied to evaluate the homogeneity of asphalt mixing section and the aluminum foam.Both of the results of these two methods are consistent with sensory analysis and the results of existed research findings,and the feasibility in actual life of these two methods are proved.