Research On The Friction And Wear Characteristics Of Contact Materials For The Conductive Slip Ring

As a key component of equipments, the wear and tear of conductive slip ring is influenced by multiple factors. It has an important practical significance to research the friction and wear properties of contact materials for the conductive slip ring. According to the demands of research project, a friction and wear test system was developed to simulate the actual working condition of the conductive slip ring. It could be continuously adjusted on contact load, electric current and speed, which met the demands of the friction and wear test.The affection relationships of contact load, electric current and speed exert to the contact material friction coefficient, wear rate and the contact resistance were studied by using orthogonal experiment method. The analytic result showed that the contact load and electric current are the main influence factors. The influence laws of contact load, electric current exert to the friction and wear properties were obtained based on the single factor experiment. According to the related theory and combining with microscopic method, the friction and wear mechanism of contact materials for the conductive slip ring was analyzed. The research results were concluded as follows:1. The friction coefficient of the two contact material decreased with the increase of contact load, and finally stabilizes. When the load surpassed a certain value, the friction coefficient increased with current increases slightly. The wear rate increases along with the increase of current, when the current increased to a certain value, the wear rate presented "U" shaped variation which decrease initially and then increases along with different load. The contact resistance of friction pair decreases with the increase of load, and tended to be stable finally.2. A suitable contact load between the frictions existed, which made the wear rate, friction coefficient and contact resistance all smaller. Under the satisfied load, the conductive slip ring presented good working performance. The appropriate contact load was varied with different contact materials.3. The wear degree of conductive ring is more severe than the wire brush. The adhesion wear, abrasive wear and arc erosion were presented during the conductive ring include worked. Under low load condition, the mechanical wear of conductive ring was light and the major wear mechanism was adhesion wear, at the moment when the current is larger, the electrical wear was the major wear mechanism, serious arc erosion appeared at this time. Under high load condition, the mechanical wear became the main wear form and the electrical wear was relatively slighter. The abrasive wear and adhesion wear were the primary wear mechanisms under these conditions.