Effect of wear particles on tribological properties of electroless nickel-phosphorous plating dispersed with PTFE and boron nitride

Since electroless nickel-phosphorous (NiP) plating itself does not have lubricating ability, studies are being undertaken to have the plating produce less friction by dispersing solid lubricants into the plating solution. However, it has been pointed out that electroless NiP plating dispersed with solid lubricants does not necessarily develop low friction characteristics. Whether or not wear particles are generated and present on the friction surface is considered to be one of the causes that determine the effect of the solid lubricants. As a result, it was found that where the plating is dispersed with a solid lubricant, both the friction coefficient and the wear resistance become low as the eutectic amount of the solid lubricant increases. When many sufficient wear particles are present, the friction coefficient is observed to come close to the value where the plating is not dispersed with a solid lubricant.