APPLICATION OF THE METHOD OF LOCAL BINARY TEMPLATES FOR A COMPARATIVE EVALUATION OF THE RELATIONSHIP BETWEEN THE STRUCTURE AND PROPERTIES OF CARBON BLACK-FILLED ELASTOMERS

Abstract

The relevance of the work is caused by the fact that a wide range of composite materials are used in the creation of oilfield equipment. Due to the ability to control properties over a wide range, carbon black-filled elastomers can provide the required mechanical and electrical characteristics. Depending on the amount of carbon black, both resistive and electrical insulating properties of structures can be provided. They are distinguished by low weight, corrosion resistance, low cost and availability of raw materials, industrial manufacturing technology. However, the heterogeneous structure, which forms a variety of properties, creates problems in selecting the composition of the material that meets specific requirements. The selection of components empirically leads to significant costs of time, financial and other resources. In this regard, it is necessary to develop and implement approaches to the study of the «structure–properties» patterns, which allow the most effective assessment of the properties of composite materials. Purpose: to evaluate the possibility of controlling the effect on the characteristics of carbon black-filled rubbers by the proposed recipe or technological solutions using tools that do not require high material costs. It was of interest to find a labor-intensive approach to assessing the structure-property patterns of carbon black-filled rubbers, which affect the value of volumetric electrical resistance, by comparing the characteristics of two materials. To do this, it is proposed to develop a method for evaluating the properties of carbon black-filled rubbers, adapted to microphotographs of the surface of the material obtained by a scanning electron microscope. The method is based on the use of the local binary templates for comparing image histograms. Methods: scanning microscopy, X-ray diffraction analysis, instrumental measurements of the electrophysical characteristics of resistive polymer composite materials, correlation analysis. Results. It is shown that micrographs of the surface of materials obtained using a scanning electron microscope can be used for a comparative assessment of the change in the volume electrical resistance of materials and its spread during mass production by comparing materials with known characteristics. Methods for comparing histograms that give correct results are defined: intersection calculation, Bhattacharya distance. The expediency of applying the proposed approach to assess the contribution of technology and type of rubber has been experimentally confirmed. The relationship between the evaluation results and the amount of the amorphous phase in the material is shown. It is concluded that the use of the proposed comparative assessment makes it possible to simplify the manufacture of a material that meets the requirements of a particular application.

Keywords

• carbon black-filled elastomers
• material structure
• volumetric electrical resistance
• electrical conductivity
• coefficient of variation
• resource saving
• local binary template method
• image brightness histogram
• intersection method
• bhattacharya distance