Abstract:When the water supply system of ship stern bearing fails or the bearing is overloaded,the local contact will occur between the metal journal and the rubber bearing and the bearing will be in dry friction state.In order to study the effect of the surface roughness of metal journal on the dry friction characteristics of waterlubricated rubber bearings,the surface microconvex of metal journal was measured by the TIME3230 surface roughness measuring instrument.The location parameter distribution curve of surface microconvex of the metal journal was obtained and the denoising was carried out.The denoised model of surface roughness distribution of the metal journal was reconstructed by Fourier transform,and the friction coefficient of the metal journalrubber bearing friction pair under dry friction was calculated according to the theory.The calculation result of the friction coefficient of metal journalrubber bearing friction pair is in agreement with that of the actual situation,indicating that the established surface roughness distribution model of the journal is reasonable.The results show that,in dry friction state,the friction coefficient of the metal journalrubber bearing friction pair is increased linearly with the incresase of the amplitude of the surface roughness function,and is increased nonlinearly with the incresase of the characteristic wavelength coefficient of the surface roughness function.When the lubrication flow direction follows the direction of processing texture,the friction coefficient is smaller than that of the vertical processing texture direction and the 45° direction of the processing texture.Therefore,the friction and lubrication performances of the metal journalrubber bearing friction pair can be improved by choosing the reasonable amplitude and wavelength of the bearing surface roughness,and the friction coefficient can be reduced by processing and assembling the metal journalrubber bearing friction pair along the processing texture.