| Friction and wear are the primary reasons of 80% invalidation in mechanical equipments, as a result of a huge economy loss, which not only waste energy and resource but also accelerate the equipments discarded and replaced. In this paper, mechanism of friction and wear reduction of laser surface texturing and behavior of contacted stress were analyzed, based on the effect of changing surface topography and structure on tribological properties, face seal system as the research target, friction and wear test and ABAQUS finite element simulation as the experimental flats. And the friction and wear discipline of laser texturing was also investigated. Experimental and theoretical basis of anti-wear technique of mechanical friction pairs can be provided in mechanical seal.Using a pulsed laser with a wavelength of 1064nm, the high-energy density pulsed laser were acted on frictional mates surfaces, forming the surface texturing structures of dimple/groove distributed equably, instructed with research achievements and literatures. Surface texturing with various dimensions, shapes and densities were generated in frictional material surfaces, by means of changing pulsed time, energy and interval. Vicker hardness between two dimples was measured to analyze the heat-affected function with laser induced. 3D topography was denoted with white-light intervene profile apparatus and the melt splashed status was observed by SEM. Simulating the face seal, friction and wear performance of texturing seal material mates PTFE/GCr15 were estimates. And the effect of various frictional mates and texturing parameters, such as diameter, depth, clearance, density and shape on tribological properties was also tested and the optimal texturing parameters can be acquired. Three-dimensional finite element simulations of sliding processing with ABAQUS software were adopted to analyze the equivalent stress with different diameters, clearances and densities.Then the alloying elements Cr, Mo were sputtered to the laser texturing steel surface by means of double glow plasma technology with the optimal technical parameters of 20mm pole interval, 800V source voltage, 880～900℃working temperature, 4h penetrating time and Ar as ambience. The intersection topography of alloying layer was observed by optical microscope, and the intersectional hardness was measured. Phases and organization were analyzed by XRD, and the ingredient of alloying layer was evaluated by SEM and EDS. The experimental results show that laser texturing can decrease the friction coefficient of PTFE ring/GCr15 disc from 0.1 to 0.075, and wear rate of mated texturing disc is 2/3 of the smooth disc with oil lubrication. After laser texturing, the PV value is increased from 6.5 MPa·m/s to 16.4 MPa·m/s and the maximal PV value can be improved by above 1.5 times. The oil film longevity is prolonged to 2 times.Compared with the tribological properties of two texturing with shape of groove and dimple, the friction coefficient of dimple-shape texturing sample is 0.065, lower than 0.08.of groove texturing sample, and the oil-storage ability of dimple is higher than the groove texturing sample. The wear rate of two texturing is about 10×10-16m3/N*m, which is 2/3 of the smooth disc of 15.3×10-16m3/N*m.For the dimple texturing mates, the friction coefficient and wear rate are decreased with diameter and depth increasing, and the oversized dimple will give a disadvantage to wear rate. With the dimple density increasing, the wear longevity is prolonged while the friction coefficient is decreased firstly then elevated. Combining various dimple parameters, it is concluded that the sample with dimples of 150μm in diameter, 500μm in clearance, 40μm in depth and 8.8% density has a optimal tribological performance, with the friction coefficient 0.055～0.06, and the wear rate is one third of the smooth sample's.Then the alloying elements Cr, Mo were sputtered to the laser texturing steel surface by means of double glow plasma technology to form the hardened phases such as Cr23C6 and Fe3Mo3C, which can increase the pressed hardness and surface hardness from HV250 to above HV1100. The intersectional distribution of soft and hard phases in matrix may improve the wear-resistance ability. Cooperating effect of laser surface texturing and double glow plasma surface alloying technology on sliding surfaces, a lower friction coefficient and better wear-resistance can be achieved.The Cr and Mo alloying layer about 20～30μm is formed on texturing surfaces by means of double glow plasma technology. The Cr concentration is 43.4% with carbide phase Cr23C6 in Cr alloying layer, improving the hardness from HV250 to HV1100. And the Mo concentration is 13.0% with carbide phase Fe3Mo3C in Mo alloying layer with HV800.After Cr/Mo sputtering process, the friction coefficient of texturing mated is decreased from 0.07 to 0.055, and the wear rate is declined from 8.1×10-16m3(N*m)-1 to 4.8×10-16m3(N*m)-1 with oil lubrication. In dry friction, the friction coefficient of texturing and alloying frictional mates is decreased from 0.16 to 0.135, and the wear rate is declined to50%. Cooperating effect of laser surface texturing and double glow plasma surface alloying technology on sliding surfaces, a lower friction coefficient and better wear-resistance can be achieved.The finite element simulating results indicate that the dimples may decrease the contacted areas, increasing the average equivalent stress. It can be seen that the stress concentration in the front and edge on contacted surface is minimized, equalizing the whole stress and reducing the stress grads. The samples with about 8%～9% dimple density have the optimal stress distribution. The simulation results are consistent with the friction tests, validating the results of friction testing to some extents.The ratios of lubricating film and surface asperity of smooth and texturing friction mates are calculated with elasticity- hydrodynamics theory to estimate the lubricating states under various load and velocity with Stribeck Curve. The texturing sample may increase the ratios of lubricating film and surface asperity, transfer the lubricated region from boundary to hydrodynamic lubrication at lower speed in shorter time, compared with the smooth.Combining the worn surfaces morphologies, the wear track in texturing disc is shallower with less ploughs than the rigorous surface on smooth. The texturing can act as a lubricant reservoir and a trap for wear particles, both affording the contact surface lubricating fluid continuously and eliminating the plowing contribution to friction.
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