Investigation of temperature effect on dynamic characteristic of polymer hybrid bearings in elastic area

Abstract

Polimer hibrit rulmanlarda bilezikler viskoelastik malzemeden bilyalar ise farklı malzemeden üretildiklerinden temas mekaniği çelik rulmanlarda olduğu gibi elastik temas olan Hertz temas ile incelenememektedir. Hertz temas yerine elasto-plastik temas modelinde Hertz temasla aynı olarak değerlendirilen temas modeli kullanılarak incelenmelidir. Elasto-plastik temas iz (indentation) model ve düzleşme (flattening) modeli olarak iki modelden oluşmaktadır. Elasto-plastik modeller elastik, elasto-plastik ve tam plastik bölge olmak üzere üç temas bölgesine ayrılarak değerlendirilmektedir. balls and rings consist of different materials. Rings have been manufactured viskoelastic material. The traditional ball bearings ball-ring contact analyse with Hertzian contact theory but polymer hybrid ball bearings has not been analyse with the Hertzian contact theory. Polymer ring-ball contact has been analysed with elasto-plastic contact model instead of Hertzian contact theory. Elasto-plastic contact model has two model which are indentation and flattening. These model have been evaluated contact area as elastic region, elasto-plastic region or plastic region. Elastic contact region evaluate the same as Hertzian contact theory. Ball bearings has long lifetime to run elastic region and away from resonance condition. Friction has been caused the systems temperature to rise while the shaft-bearing system run. This condition has been caused to drop elastic modulus and stiffness of polymer bearing. Elastic modulus has been affect the bearings force capacity and stiffness. Stiffness affect the natural frequency of systems. For researching temperature effect on elastic modulus and vibration characteristic of ball bearings mathematical model has been created. Radial deep groove ball bearings geometric and material properties have been used in mathematical model. Simulations have been done via MATLAB software program. As a result, elastic modulus and natural frequency of systems' decreases with temperature rise. Although force capacity related with elastic modulus, force capacity increase with temperature rise because of critic deformation.