INFORMATION PROVISION OF TECHNOLOGICAL OPPORTUNITIES FOR DEFECT-FREE PROCESSING OF PRODUCTS MADE OF MATERIALS PRONE TO CRACK FORMATION

Abstract

The work aims to provide information on technological possibilities for defect-free processing of products from materials prone to cracking since their surface layer has hereditary defects of structural or technological origin. The products’ strength and functionality depend on the inhomogeneity and defectiveness of the structure of the materials from which they are made. Such materials have many different micro defects formed in the surface layer of parts during the technological operations of their production. Reducing marriage in the finishing operations of these materials and increasing the operational properties of products made of these materials is an essential national and economical task, the solution of which leads to a significant saving of material resources, labour intensity and cost of manufacturing parts. The currently available information on the thermal processes of diamond abrasive processing is obtained based on the homogeneity of the polished materials. It does not consider the presence of defects in the technological heredity of the products. The phenomenological approach in studying the causes of cracking of materials prone to this type of defect does not allow to reveal the mechanism of genesis and development of grinding cracks. The choice of the method of investigation of the mechanism of crack formation is based on micro-research related to inhomogeneities, which are formed in the surface layer of parts during previous technological operations. The following tasks are solved in the work. The mechanism of the formation of grinding cracks in the surface layer of materials and alloys prone to crack formation during diamond-abrasive processing has been studied, taking into account previous operations and hereditary inhomogeneities that arise. A mathematical model has been developed that describes thermomechanical processes in the surface layer during grinding of parts made of materials and alloys, taking into account their inhomogeneities, which affect the intensity of the formation of grinding cracks. Calculated dependences between the crack resistance criterion and the main controlling technological parameters were obtained. According to the known characteristics of hereditary defects, the limit values of thermomechanical criteria, which ensure the necessary quality of the surfaces of the processed products, are determined. An information base has been created to design technological operations of grinding materials with hereditary inhomogeneities, ensuring maximum productivity while ensuring the necessary quality indicators. Based on the obtained criterion ratios, an algorithm was built to ensure technological capabilities for defect-free processing of products from materials prone to loss of quality of the surface layer of parts.