Determination of tribology behavior of self lubricant surfaces by using selective laser melting method

In the machinery industry, it is expected that the products used will be long serviceable. Wear damage is one of the most important factors that reduce the life span of machinery and equipment. In addition to good design, it is inevitable to apply a lubricant between the contact surfaces to prevent wear damage. One of the methods used to reduce the wear rate is the use of self-lubricating surfaces. Today, besides the use of solid lubricant films as self-lubricant, sintered surfaces produced by powder metallurgy by impregnation with liquid lubricant after production are also widely used. With the development of technology, sintered bearings have started to be produced by additive manufacturing methods in recent years. The advantage of this method over powder metallurgy is that it allows to obtain complex geometric products due to the lack of geometry limit. In this study, three different geometries were designed in computer aided design (CAD) and analysis programs and lubricant flow modeling was done in computer environment. In the data light from the flow model, the best lubrication design of its surface is produced by the selective laser melting (SLM) method. 316L stainless steel powders are used in production. As a result of the data obtained from the flow model, the best design which lubricates its own surface was produced by the selective laser melting (SLM) method. 316L stainless steel powders are used in the production. And then the produced samples were divided into two groups. The samples of the first group were kept in the liquid lubricant and the samples were impregnated with oil. Any treatment was not applied to the other group. Wear tests were performed at 5-10 Newton (N) loads and 100-200 (RPM) velocities. After the wear tests, the wear volumes of the samples were calculated by 3D profilometer. Finally, the internal structure of the samples and the areas of wear were examined by Scenning electron microscopy (SEM). As a result of this study, it is seen that, the oil has been reached the samples surface and when compared with untreated samples, the wear rate is reduced. Hence, it has been seen in tribological tests as well as in the flow model that the design is self-lubricating.