APPLICATION OF VEGETABLE OILS FOR THE FRICTION PAIR MODIFICATED WITH A BORON

Abstract

In the article, the results of the conducted research were discussed, and the aim was the evaluation of the characteristics of the operation of sliding pairs when vegetable oils are used for lubrication. Particularly, friction pairs with hard layers containing boron were taken into account. For comparison, two of the most common vegetable oils were used during the tests. Rapeseed oil was chosen, since it is most frequently applied in Europe, soybean oil was chosen due to its occurrence in North American areas. The oils are also applied in industry for commercial aims as oil bases for lubricants. The products based on vegetable oils can constitute an alternative for those of mineral origin. However, vegetable oils are characterized by different properties than mineral oils. The most essential issue is the fact that biolubricants are free of sulphurcontaining compounds that can have an unfavourable influence on the health of human beings. The wear measurements were conducted on a block-on-ring test stand T-05. In the sliding pair lubricated with vegetable oils, steel specimen interacted with a counterpart made of bearing alloy. In the second variant of a friction pair, a steel ring specimen with a boronized surface layer was used. The changes of the surface roughness of the specimen and counterpart during operation were evaluated. In the comparative evaluation, the best results were obtained choosing the sample with the hard layer lubricated with soybean oil. In this case, the observed wear of the surface of sliding pairs was the lowest. The lowest friction force and the lowest temperature of the elements of the friction pair also corresponded to this. The application of the TiB2 layer allows reducing the wear of both the sample with the layer and the counterpart with the bearing alloy layer.