Analysis On The Materials Meso-structure Based On Digital Image Processing

Effect of the kind of buffer and waterproof agent on the process of hydration of building gypsum and the mechanical properties of gypsum particleboard (GPB) were analyzed by other member of the workgroup. The results of qualitative analysis showed the kind of buffer and has the different effect on the setting and hardening of building gypsum, crystalline habit of dihydrate the physical and mechanical properties of GPB. For example, consequently leading to the transformation of dihydrate crystal from needle-like to short prismatic. Furthermore the higher the dosage of citric acid, the larger the dihydrate crystal is. The internal bond strength, the modulus of rupture and modulus of elasticity of GPB were the highest when the citric acid of 0.05%～0.1% was added. The above mechanical properties were reduced obvious as high content citric acid was added. But the dihydrate crystal is slender when the waterproof in an appropriate concentration was added, and the mechanical properties of GPB were increased.In the field of materials research, the people think that the evolvement of the materials meso-structure leads to the transformation of the mechanical properties of materials. Considering the above results of qualitative analysis can not explain why did the transformation of the mechanical properties happen from the point of view of the materials meso-structure, a method of quantitative analysis of materials meso-structure is set up using digital image processing , which will quantificationally explain what is the cause of the transformation of the mechanical properties.Based on powerful image Function of MATLB and digital image processing theory, the program and methods using to process and analyze the SEM images of gypsum board and GPB were developed, the system configure, some main methods of image processing and analysis, measuring characteristic parameters of microstructure and analyzing error are described in detail., and moreover, the feature parameters for the materials meso-structure were measured and analyzed, such as the grain distribution, the grain size and the tangent rectangle size of the gypsum grain. The application of metallographical analysis to the above program and methods, proved which were adaptive. At the same time, on the base of the practice, the general procedures of preparing of specimens of gypsum-based materials for SEM images analysis was also described in this article.Compared the results of qualitative analysis and of quantitative analysis, the result show that the program and methods using to process and analyze the SEM images of gypsum board and GPB is feasible and exact. So the analysis methods of materials meso-structure based on computer image processing is of practicability.