Propertie Study Of Self-lubricating Composite Material At Room / Low Temperature And Bionic Of Design Bearing

With the rapid development of science and technology,especially,the special mechanical structure working under special conditions.Some bearings of wind turbines,which work in demanding conditions at high and low speed under low temperature environments,the grease lubrication was fails,the transfer film provided by the selflubricating material in the bearing which could help for the normal operation of the bearing.At present,China is speeding up the development of independently designed large wind turbine and high-grade,high-precision,advanced technology,all of which have put forward urgent requirements for the self-lubricating composite materials of long life and high stability.Therefore,it is great value and significance to develop new self-lubricating materials that study the mechanism of self-lubricating friction and wear of composite materials and to solve the problems for life extension and reliability of bearing under low temperature conditions.In this paper,the main friction and wear mechanism of bearing self-lubricating composite materials under two conditions of normal temperature and low temperature were analyzed,which provides a basis for design and research of self-lubricating composite materials.The packing ratio,forming process,pressing condition and sintering temperature of UHMWPE matrix self-lubricating composite were studied.The aim of high efficiency preparation of composite materials was achieved.In room temperature environment,the effects of the content of reinforcing filler and lubricating filler for the friction and wear properties,mechanical properties and thermal properties of composite materials were investigated.At-60? environment,the friction and wear properties of composite materials,research of UHMWPE+CF+POB+Cu composite was test,composite wear surface and the grinding surface was investigated,and explore its friction and wear mechanism.In room temperature environment,the friction and wear properties of UHMWPE matrix filled with carbon fiber were studied,the coefficient of friction of carbon fiber reinforced UHMWPE composite varies from 0.12 to 0.30,and the wear rate is also high,the optimum friction and wear performance of carbon fiber reinforced UHMWPE composite was obtained,the optimum ratio is UHMWPE+15%CF composite.When the POB filler filled with the UHMWPE+15%CF composite,the wear rate is further reduced.the wear rate was the lowest than other composites when nano Cu filled with UHMWPE+15%CF+15%POB composites.The lowest wear rate is UHMWPE+15%CF+15%POB+12%Cu composite.The wear rate of the UHMWPE+15%CF+15%POB+12Cu composite is about 1/16 of the pure UHMWPE.At the same time,the friction and wear properties of the UHMWPE+15%CF+15%POB composite materials filled with graphite were investigated.Although the coefficient of friction was reduced,the wear rate was increased greatly.The mechanical properties,POB,graphite and nano copper particles all reduce the impact properties of composite materials.The thermal properties,the thermal enthalpy of composites was improved,which promoted the improvement of crystallinity.The thermal conductivity,nano copper particles and graphite can improve the thermal conductivity of the composites.At the same time,the effect of the composite material at different loads and sliding speeds under room temperature was investigated.Research result show that the effect of sliding speed on the wear rate of composite materials is greater than that of load.The coefficient of friction of composite was decreases with the increase of load,and the coefficient of friction of composite was increases with the increase of sliding speed.Low temperature friction and wear testing machine was developed and five kinds of UHMWPE composites of the friction performance was tested under-60? low temperature environment.At-60? environment,with nano Cu content was increased,the coefficient of friction of fiber reinforced ultra-high molecular weight polyethylene composite material is also more stable than that UHMWPE composites without nano Cu.The wear rate of composites at low temperature is lower than that at room temperature.At low temperature environment,the content of nano Cu was increased,the lower of the wear rate of composite materials and the main wear mechanism is fatigue wear.At-60 ? low temperature environment,compares the wear rate of the UHMWPE+CF+POB+12%Cu composite in the different load and different sliding speed.Research result show that the load increased from 100 N to 300 N,the coefficient of friction of UHMWPE composite decreased with the increased of the load,and the wear rate of the composite was increased with the increase of the load.With the increase of sliding speed from 100r/min to 300r/min,the coefficient of friction of UHMWPE+CF+POB+12%Cu composite has an increase trend.The wear rate and wear loss of UHMWPE+CF+POB+12%Cu composite materials first decrease and then increase with the increase of sliding speed.At-60? low temperature environment,the speed relative to the wear rate is higher than that the load relative to the wear rate.At the same load,the bearing capacity of common bearing and bionic bearing was analyzed by ANASYS software.Under static loading,the von-mises stress of bionic bearing is less than that of common bearing,the arrangement mode of bionic hole groove and the diameter of hole groove was affect the bearing capacity of bearing.Under dynamic loading,the maximum stress value of the bionic bearing von-mises is the minimum,the pressure state is optimal.Finally,the bionic structure model was the final bearing structure.The bionic hexagon with circumscribed circle diameter of 10 mm is arranged at 30 degrees was the final bearing structure.