Preparation And Property Study Of Filled PTFE/Cu Inlaid Solid Lubricating Composites

At present, the inlaid solid lubricating material was prepared complicatedlyby traditional way, to press the shaped self-lubricated composites. In this way,the matrix and lubricated composites was bonded loose with each other. Thetribological behavior of inlaid solid lubricating material was sliding and it wasstudied in lighter load. There was very little research about initial static frictioncoefficient and wear quantity under extreme loading conditions. In order to solvethese issues, this paper used the way of Moulding and sintering to prepare thecomposites of PTFE/Cu with the inlaid structure. The PTFE/Cu composites wereshaped one step, and the process routing was simplified. The friction coefficientand the wear quantity were studied under the extreme loading conditions from20MPa to50MPa.SEM showed that the fillers of graphite and MoS₂distributed evenly in thePTFE matrix on macro point, but on the micro point the fillers reunited on asmall scale. The adding of graphite and MoS₂decreased the crystallinity ofPTFE and the Crystallization relaxation temperature to varying degrees, andincreased the compressive strength. In the range of-50℃⁵0℃, thelinearexpansion coefficient of filled PTFE composite was lower than that of purePTFE, improved dimensional stability.For the composites with annular groove, sample of30vol%graphite+10%MoS₂had the lowest initial coefficient of static friction and dynamic frictioncoefficient. And with increasing pressure, the friction Coefficient became lower.Grit blasting at the surface of metal matrix could significantly improve thebinding ability of filled PTFE and metal matrix, and improve the tribologicalproperties. In the process of friction, circular holes distribution uniformity canform the continuous transfer film quickly, and got the best lubrication effect.When the size of the holes was Φ6mm, the lubricating composites were moredense,and bonded closely with the metal matrix. In the process of friction thelubricating composites would protrude more from the worn surface. That was infavor of decreasing the friction coefficient. The fillers blocked the transfer ofPTFE sheet to friction pair. The abrasive dust became tiny, and the wear quantitybecame lower.