Molecular dynamics study on friction of polymer material polyoxymethylene (POM)

Abstract

Abstract Polyoxymethylene (POM) which shows good mechanical properties has a wide range of application in engineering. In this work, the nanoscale simulation method of molecular dynamics (MD) is used to make a more systematic simulation and calculation of the model of the resin material POM. With the application of software, the influence of friction depth, temperature, and sliding velocity on the frictional properties of POM was studied. The main conclusions are as follows: (1) In the range of 300 K–400 K, the temperature has little influence on the friction coefficient, but the fluctuation of friction force becomes larger as the temperature becomes larger. (2) When the friction depth increases, the plowing phenomenon and the accumulation of debris become more obvious and plastic deformation of POM increases. (3) When the friction velocity is changed, it is found that there is not much correlation between friction force and friction velocity, but as the friction velocity decrease, the friction force also decrease to a smaller extent. (4) The friction force will experience a growth period, and its value gradually stabilizes with some fluctuations, which are mainly caused by the atomic thermal motion, the effect of abrasive chip accumulation, and the release of stress energy caused by deformation.