Study Of Numerical Simulation On Reciprocating Wear Under Boundary Lubrication Condition

The research on tribological system has mainly focused on the acquisition of systemic characterization and the wear conditions of components based on a mass of tests for years. However, due to the complexity of tribological system, it is definitely difficult to gain accurate quantitative wear laws to monitor/predict wear status or provide a guide for tribological design. Tribological simulation was born to solve this problem to some extent. It has been rapidly developed in recent years. This paper has conducted the boundary wear numerical simulation based on boundary wear theories and cylinder-piston ring tests.Numerical simulation technology used in tribology system is to study tribological system which has been built or not, establish simulation model and test the model constantly using computer technology. Out of question, simulation model is the key point. According to classical adhesive wear model and tribo-fatigue knowledge, combined with the characters of boundary wear, a computation model of boundary wear was established. It is crucial to determine the parameters and verify simulating model. Therefore, a series of cylinder-piston ring tests have been investigated to verify the simulation model. Finally the finite element method and discrete method have been used in stress analysis, wear computation and realization of the wear simulation.The results of cylinder-piston ring tests under boundary lubrication have indicated that the trend of boundary wear changing with load and speed accords with the above model. Moreover, pin-on-disc testing results have validated the reliability of the model as well. According to microscopy analysis of wear surface, cylinder-piston ring's wear under boundary lubrication is mainly adhesive wear. Simultaneously, the surface of the cylinder with low hardness appears furrow and the wear of piston ring with high hardness against the cylinder with low hardness suffers from two-body abrasive wear. However, the appearance of oxide film and scleroticsurface decreases the wear to some extent.On the basis of theoretic analysis and test validation, the Finite analysis tool ANSYS and the programming language Visual Basic have been adopted to develop the simulating software of cylinder-piston ring boundary wear. The software mainly includes four functions: contact stress simulation module, wear simulation module, surface morphology and debris morphology simulation module, and data management module. The software can record and manage test data, compute the contact stress of wear surface using FEM and simulate the boundary wear. It can also provide plenty of images of surfaces of components and representative wear particles and their character description to analyze and predict the wear condition.