Simulation Of Wear Performance And Optimization Welding Process Of Tin-based Babbit Brazing Layer

With the rapid development of industry,the tin-based babbit,because of its excellent adaptability,embedment and wear resistance,has been used as a bearing wear resistant material for ship and space equipment.This has put forward higher requirements for the preparation and wear properties of tin-based babbit wear-resistant layer.Therefore,it is necessary to study the friction and wear properties of tin-based babbit alloy TIG brazing layer and optimize the welding process.This article uses different welding currents to form a good quality tin-based babbit wear-resistant layer on a Q235B low carbon steel substrate.The microstructure of the tin-based babbit alloy layer was analyzed by metallographic microscopy(OM)and X-ray diffraction(XRD),and microhardness tester.Image processing software was used to statistically analyze the hard phases in the babbit alloy layer.The effect of TIG brazing current on the brazing interface structure and the microstructure in the tin-based babbit alloy layer was investigated.The results show that with the increase of welding current,the bonding strength between the substrate and the tin-based babbit alloy layer increases,and the content of the hard phase in the tin-based babbit alloy layer also increases and the distribution becomes more uniform.The friction and wear properties of the tin-based babbit alloy brazing layer were tested by friction and wear tests,and the wear scar was analyzed by confocal laser scanning three-dimensional microscopy.The effects of welding current,friction and wear test conditions on the friction and wear properties were investigated.The results show that when the welding current is increased from 50A to 90A,the wear rate of the babbit brazing layer decreases from 47.68×10~4μm ~3/(N·min)to 14.62×10~4μm~3/(N·min)and the friction coefficient decreases from 0.317 to 0.256 due to the increase of hard phase SbSn and Cu6Sn5 content and the increase of hardness,which improving the wear resistance of the tin-based babbit alloy brazing surfacing layer.Based on the Archard wear calculation model,combined with the results of the friction and wear test of the tin-base babbit alloy layer,the wear coefficient K_d was fitted and a theoretical model of sliding wear calculation was proposed.The mathematical relationship was?=(,,).The three-dimensional finite element model of the pin on disc sliding wear was established and the UMESHMOTION subroutine was embedded the modified Archard wear calculation model.Using ABAQUS adaptive mesh technology,the wear calculation model was embedded into the finite element program to simulate the wear properties of the tin-based babbit alloy brazing layer under different test conditions.The computer simulation results were compared with the experimental results to verify the reliability of the method,and also to illustrate the accuracy of the sliding wear calculation model,and to predict the life of dry friction wear of the wear layer.At the same time,based on the sliding wear model and combined with the process tests,the welding process is optimized,which saves a lot of manpower and material resources,and can greatly shorten the research period.