CONTACT INTERACTION OF DISCRETE-CONTINUALLY STRENGTHENED PARTS OF INTERNAL COMBUSTION ENGINES

Studies of the stress-strain state of discrete-continuously strengthening parts of internal combustion engines are described in the paper. A parametric model of a microcell containing a two-part cell has been developed. The first part simulates a fragment of an aluminum part with a surface corundum layer. The second part is a fragment of a cast iron part with a zone of discrete strengthening of steel. Vary: modulus of elasticity of the corundum layer material and the shape of the discrete hardening zone. The dependences of the strength and stiffness characteristics of the studied system on the varied parameters are established. They are the basis for substantiation of rational modes of technology of discrete-continuous strengthening of parts of internal combustion engines. In the course of research, it was found that previously determined for discrete strengthening, the effects of a favourable redistribution of contact interaction between parts are preserved for discrete-continuous strengthening. The characteristic dependences of the features of the stress-strain state of the elements of discrete-continuously strengthening parts on the varied properties of the surface layers of the continuously strengthened part, on the one hand, and the shape of the discrete strengthening zone, on the other, are determined. This makes it possible to determine the sensitivity of the characteristics to purposeful or random variation of these factors. It is also expedient to set and solve optimization problems to determine such modes of technological operation of discrete-continuous strengthening, which increase the characteristics of strength, durability, efficiency of internal combustion engines and other machines, units and assemblies containing such strengthened parts. The developed approach, models and research methods will be further applied to studies of the stress-strain state of contacting discrete-continuously strengthened parts of structures to improve the technical and tactical and technical characteristics of products of machine-building enterprises.