On Abrasive Wear Under Dry Contact

With the development of industry engineering and the progress of science and technology,the high precision of machines and the accurate prediction of service life are becoming more and more important topics in industrial production.For the operation of mechanical parts,such as bearing and gear,wear is one of the main factors that affects the work precision and life prediction.The mechanical wear widely exists in the work of mechanical parts,and is one of the main causes of mechanical failure.Dry contact abrasive wear is a common form of mechanical wear.The objective of studying it is to reasonably reduce the influence of Abrasive wear on the work precision of machines and the prediction of service life,thereby improving the work precision of machines and the prediction of service life.Therefore,study on the abrasive wear under dry contact is important for industrial production.The first part of this thesis introduced the effects of abrasive wear under dry contact on mechanical equipments' properties and the engineering significance of abrasive wear under dry contact.The mechanism of abrasive wear was expounded and the calculation model of abrasive wear was brought out,and the research method of abrasive wear was summed up with a brief analysis made.At the end of this thesis,the main contents of this thesis were briefly described.The second part studied the abrasive wear of the four possible shapes of abrasive debris.They are spherical,conical,round platform and Pyramid in shape.And the abrasive wear of three shapes,namely spherical,conical and round platform,was emphatically analyzed by Matlab.Thus,the wear rate and friction coefficient and reflections of them with debris size,shape,the number of debris or related parameters had been obtained.In the third part,the contact model of spherical,conical and round platform abrasive debris was studied,and the spherical fractal abrasive contact model was obtained with double fractal analysis of spherical particles.With the finite element software Ansys,the model of abrasive wear was established.The Mises stress and shear stress distributions for four kinds abrasive debris contact model had been computed,and the relationships between the Mises stress and shear stress distributions with the depths of subsurface were analyzed.In the fourth part,the spherical,spherical fractal,conical and round platform abrasive debris sliding models for abrasive wear were studied with the consideration of frictional heat.with the finite element software Ansys,the temperature and thermal stress distributions of the four kinds of debris sliding models and the stress distributions of static contact models were studied,which were compared with the results of the sliding models.And the relationships between the stress distributions with the depth of subsurface were analyzed.The fifth part is the summary and prospect.First of all,it presented the main conclusions of this thesis,and then put forward the content and direction that need further study in the future.