Changing Cohesive Energy Between Atoms in Metal-to-Metal Transition Layer for Fe–Sn and Fe–Cu–Sn Compounds in the Course of Spark Alloying Process

There have been analyzed design and technological methods to improve quality of Babbit sliding bearings (SB). A process for forming intermediate layer of copper by the electrospark alloying (ESA) method is described. The process provides strong adhesion of steel substrate to antifriction babbit layer, as well as more intense heat removal from the friction zone. The numerical values of the cohesive energy between atoms in the metal-to-metal transition layer with the use traditional (Fe–Sn) and proposed (Fe–Cu–Sn) technologies have been determined. The feasibility of using copper to increase the cohesive strength of the babbit layer to the steel substrate has been proved. It has been stated that in the case of combining the elements according to the compound system scheme of Fe–Cu–Sn, the cohesive energy in Sn increases, and with the elements being in the sequence Fe–Sn, it decreases. When combining metals according to the scheme of Fe–Sn, the weakest link of the compound system, namely Sn, results in decreasing the strength of Sn and strengthening Fe, and when doing it according to the scheme of Fe–Cu–Sn, the weakest link of Sn is strengthened.