Technology of self-repairing and reinforcement of metal worn surface

Adv.Manuf.(201 3)1：102-105DOI 10.1007/s40436-013-0009-2Technology of self-repairing and reinforcement of metal wornsurfaceYi xu·Fei Gao·Bo Zhang·Feng NanBin.Shi XuReceived：8 September 2012 1Accepted：15 November 2012/Published online：13 M arch 2013### Shayghai University and Sp nger.Vedag BeNin Heidelberg 2013Abstract Researches on self-repairing material(serpen-fine phyllosilicate)of our team in the past few years，suchas ultrafining treatment，surface modification，self-repairingmechanism，the effect of rare metal on the self-repairngperformance of serpentine，were introduced summarily。

The phyllosilicate of serpentine shows excelent tribologi-ca1 and self-repairing performance for metal worn surfaceas additive in lubricant。

Keywords Self-repairing performance·Self-repairingmechanism ·Serpentine1 IntroductionFriction and wear.as one of the main causes of materialsfailure。has attracted more and more attention all over thewor1d1，21.In recent years，micro-nano scale phyllosilicatecomposition(the main component is serpentine)developedby Russian researchers exposed favorable self-repairingperformance at practical application[3].Jin et a1.[4]studiedthe tribological performance of serpentine by using the ser-pentine additive in diesel engine of locomotive，and theresults indicated that certain thickness of self-repairingprotective 1ayer can be formed on the iron worn surface。

Moreover，the self-repairing protective layer possessesY.Xu f圜 )·F Gao·B.Zhang-F.Nan·B，-S.XuNational Key Laboratory for Remanufacturing，The Academy ofArmored Forces Engineering，Beijing 100072，PeoplesRepublic of Chinae-mail：xuyi0226### vip.sina.eomF.NanSchool of M aterials Science and Engineering，Shanghai JiaoTong University，Shanghai 200240，Peoples Republic of China鱼Springerlower surface roughness，higher microhardness and very lowfrictional coefficient.Zhang et a1.f5]indicated that the tri-bological performance of metallic tribo-couples wasimproved and the friction temperature was reduced by add-ing micro-nano scale natural serpentine powder fSP)intobase oil.The self-repairing technology for the metal wornsurface of mechanical equipments under the running con-ditions，by using lubricating oil as carrier to transport themicro-nano scale into the jnterface of tribo.couples.couldaccelerate the form ation of self-repairng protective 1ayerwith a dynamical thickness on the worn surface.Thereby，theformation of self-repairng protective layer on worn surfacecould reduce worn and prolong remarkably the service life ofequipments f2.It is notable that there are numerous researchreports on the tribological performance of phyllosilicate self-repairing material，but the self-repairing mechanism in thefrictional course did not get to a common view。

Our research team has been hammering at researchworks about serpentine(a kind of phylosilicate)in the pastfeW years. such as surface modification.tribologicalproperties，self-repairing mechanism，and so on.In thisPaper，some research work was introduced summarily。

2 ExperimentalFriction and wear tests were performed on a RFT-III bo-meter with a pin.on.block configuration at room temperature[6，7.The upper sample was a pin with a diameter of 8 ininand a height of 30 mm.and the lower sam ple was sectionedinto 70 am × 14 nm × 14 mm block.The pin makes oscil-lating movement(50 mm in amplitude1 on the top of block。

Both pin and block were made of 45#stee1.The tribologicaltests were conducted with a load of50 N and a sli出ng speed of1.0 m/s.A1 the specimens were ultrasonically cleaned in anTechnology of self-repairing and reinforcement 1054.Jin YS，Li SH，Zhang ZY et al(2004)In situ mechanochemicalreconditionin2 of wom ferrous surfaces.Tribol Int 37(7)：56 l-5675.Zhang B，Xu Y，Zhang BS et al(201 1)Tribological performanceresearch of micro-nano serpentine powders addictive to lubricantoil.Adv Mater Res 154(155)：220-2256.Gao F.XU Y.XU BS et al(20l11 Study on self-repairing per-formance and formation mechanism of self-repairing 1ayer ofnatural serpentine powder as a lubricating oil additive.Tribology31：431-4387.Zhang BS，XU Y，Gao F et al(2011)Sliding friction and wearbehaviors of surface-coated natural serp entine mineral powdersas lubricant additive.APPl Surf Sci 257：254OL-25498.Zhang BS.Xu Y，XU BS et al(201 11 The self-reconditioningeffect of the phylosilicate lubricating material on Fe-basedtribopairs.J Funct Mater 42(7)：1301-13089.Zhang BS(201 1)Preparation of selr-reconditioning materialsbased on metastahle serpentine mineral and investigation on theirtribology mechanisms. Dissertation， Shanghai Jiao TongUniversity10.Zhang BS，Xu BS，XU Y et al(2011)CU nanoparticles effect onthe tribological propeies of hydrosilicate powders as lubricantadditive for steel-steel contacts.Tribol Int 44：878-88611.XU Y，Zhang BS，XU BS et al(201 1)Thermodynamic charac-teristics and tribological properties of lanthanum/serp entinecomposite lubricating materia1.M ater Sci Eng Powder M etal116f3)：349-35412.Zhang B，Xu Y，Gao F et al(201 1)Tribological characteristicsand self-repairng eflfect of hydroxy-magnesium silicate on vari-OUS surface roughness friction pairs.J Cent South Univ Technol18f5)：1326-1333垒Springer