Rybalko I. Increase of wear-resistance of parts by means of providing homogeneous metal structure with the introduction of powder composition

The important scientific task for small workshops, which aims to use the compositions for hard-facing differing in chemical composition with the use of carbon or low-alloy wires, has been solved. A method of restoring and strengthening of parts that allows to adjust quickly the value and composition of the alloying components using available wires with powder dopants has been developed. By means of theoretical and experimental studies the parameters of hard-facing of meshes on the surface of the wire, which provide dosed introduction of alloying components, have been established. As studies have shown, it is possible to correct the crystallization conditions that affect the level of stresses and deformations possible by changing the feed rate of the wire. The recommended feed rate enhances the crystallization process time and serves the achievement of a uniform structure at their intersection. Introduction of powder PG-10N-01 in the liquid bath provides 2-2.35 times' increase of wear resistance of coatings. The segregation of components in the heat-affected zone has been investigated, the possibility of using it in service has been shown. It was determined that replacement of cored wire by a new process of restoring seats for the bearing of diameter 35 mm shaft (tractor T-40M transmission mechanism shafts, main clutch shafts, T-16M gearbox secondary shafts, T-150K-09-25, KhTZ -17 221, T-150-05-09-25 tractor transmission shafts, KAMAZ-740.11-240, JAMZ-236, JAMZ-238, JAMZ-240 engine compressor crankshafts) in the amount of 1100 pcs. (up to 550 pcs. parts) provides the economic benefit of 5115 UAH. Taking into the consideration the prolongation of the service life of shafts in operation as to compare with wire H-30KhGSA, as well as its introduction with additional doses of powder PG-10N-01 the economic benefit is 6919 UAH per year. The total economic benefit of the introduction of new technology of restoring of parts and increase of their operational stability is 12034 UAH per year.