Datsyshyn O. Computational models of fracture mechanics for estimation of solids life under their cyclic contact interaction

Object: fatigue of deformed solids under cyclic contact. Purpose: development of calculation models for fracture processes research and residual life evaluation of solids under cyclic contact. Methods: approaches of fatigue fracture mechanics of materials; method of singular integral equations. Results: calculation model and algorithms of cracks propagation paths by step-by-step construction in the solids contact zone and evaluation on this basis their durability are proposed; the model is applied to rolling and fretting-fatigue contact interactions; cracks propagation paths (systems of edge cracks, subsurface crack) are investigated in view of the materials crack resistance characteristics and tribojoint operational conditions; computation examples of contact life, and also debris size are given. Novelty: the model provides curvilinear cracks growth, fracture mechanism change (shear/opening), general contacting conditions between joint elements and between crack faces; new singular integral equationsof two-dimension contact tasks of the elasticity theory for solids with curvilinear cracks are constructed and solved; conditions for debris size determination are formulated; the formation laws of rolling bodies typical damages are established: pitting, spalling etc. Application: for optimization of wheel-rail system parameters in Institute of black metallurgy NASU. Use: transport, mechanical engineering, energetics.