Mechanisms of wet abrasion for nitrile rubber (NBR), polytctrafluoroethylene (PTFE) and fluoropolymer alloy (F50-1) have been investigated. Specimens were held against a rotating steel disc. Both the specimen and the steel disc were immersed in an abrasive liquid of the type used for oil-well drilling. The abraded surfaces of samples were examined using scanning electron microcopy. It is concluded that wear occurs as a result of two different mechanisms: a local microteadng process and a general microlayering or nlicropolishing process. Wear rates of polymeric materials have been found to increase with increasing sand content of media and with decreasing sliding speed. Mostly, these rates of bear also increase with normal load. However. wear rates of F50-1 were found to be surprisingly insensitive to normal load at 100℃.

rubber, nylon-6 and polytetrafluoroethylene, have been investigated using a specialabrasive erosion test machine designed by the authors. Based upon some observations ofthe abraded surfaces of test samples using scanning electron microscopy (SEM), themechanisms of abrasive erosion for the polymers examined could be summarized asfollows: a mierocutting action of the abrasives with a certain kinetic energy; microdelamination of the surface layer of the materials resulting from initiation andpropagation of microcracks; mechanochernical and thermal decomposition of materials;and surface peeling, resulting from plastic fracture expanded from local plastic deformationof the material. The influence of these factors on the wear rate of the abrasive erosion hasbeen studied, and the relevant wear-rate equations are presented.

A new energy theory of rubber abrasion by a line contact hasbeen set up through analyzing the energy distribution andconversion during the abrasion process, corresponding theoreticalwear equation of rubber abrasion by a line contact in unsteadystate has been derived. This energy theory, which is animprovement on the previous theory of rubber abrasion by a linecontact, can be used to clarify the phenomena and processes ofthe rubber abrasion.

Achievements in research on robber wear by the present aulhor and his group over the past ten years arc summarized briefly Tbcsc results include mechanisnls and wear equations for dry and wctabrasion, basic features and wear nlechanism of oily abrasion, tbeory of dry abrasion by a line comtact, physical processes and surface mecbanocbcmical effects of abrasive erosion. They are not only significant in the context of rubber tlibokrgy bu; are also valuable for extending tile working life of rubber components