ABRASION RESISTANCE OF RESTORATIVE COATINGS FOR CRANKSHAFTS AND BEARINGS IN AGRICULTURAL MACHINERY

The paper presented examines the dynamics of wear of restored parts using different materials for the friction pair. The pair of crankshaft and sliding bearing largely determines the machine service life - although their overall wear index is less than 1%, it can still lead to a large number of failures and malfunctions. Vibrating arc overlaying in a shield of gas mixture of 60% argon and 40% carbon dioxide was used for restoring the surface of rollers. Subsequently, these were treated by heating with high-frequency current (HFC) and lowered to a hardness of 55 +/- 2 HRC and ground to the final size. It was found that the antifriction coating of plain bearings with electrochemical lead alloy EO92 showed excellent performance and insignificant wear in combination with reference material St45 and welded coating DUR500. In combination with electrochemical lead alloy EO92, the welded coating DUR500 showed a significantly higher wear on actuation compared to the reference material St45 at sliding friction. The relative wear resistance enhancement of crankshafts and bearings by restorative coatings represents an essential measure, as their service life can be prolonged by 20-50% in contrast to the new parts without restorative coatings.