Determination of parts tolerances in friction knots of grey and nodular cast iron with thermal diffusion platings vanadium and chrome

Abstract

Abstract. In the study, experiments with a vanadium coating of samples were conducted, to establish the limits of the increase in the landing dimensions and the designation of limiting deviations in dimensions and the designation of limiting deviations in the dimensions of the manufactured parts. The maximum deviations relative to dimensions of cast iron parts with thermal diffusion platings vanadium and chrome in friction knots of machines and mechanisms were explored. The plate thickness and the linear sizes increment of gray and nodular cast iron hardened products were determined. Were obtained uniform in thickness carbid platings as a result of the experiments on producing of thermal diffusion vanadium and chrome plating.

Predicting the Thickness of the Hardening Coating during Diffusion Metallization of Cast Iron

“…For the thermal diffusion hardening of specimens of high-strength cast iron VCh 60, the following components were taken from the powder medium [8,9]:…”

“…Changes in the overall dimensions of the samples were carried out using a scanning electron microscope after chemical thermal treatment [13].…”

“…The found values of 𝑙𝑙𝑐𝑐(𝐾𝐾 2 𝐷𝐷 0 ) and 𝑙𝑙𝑐𝑐(2𝑝𝑝) were substituted into equation (9) and found the values of 𝑐𝑐𝑡𝑡𝑡𝑡 and 𝐸𝐸 for the corresponding temperatures (Table 2). The calculated values of the activation energy of diffusion 𝐸𝐸 made it possible to obtain an empirical formula for the dependence of the thickness of the diffusion layer δ on the temperature 𝑇𝑇 and the time of diffusion saturation 𝐷𝐷.…”

Investigation of the Strength of Diffusion Coatings on Cast Iron Friction Pairs in Contact with Hard Abrasive Soil Particles

“…The limit wear of cast iron parts is limited to 0.3 mm. Therefore, a hard wear-resistant coating is applied to the surface of cast iron parts by diffusion, which increases their service life [7][8][9][10]. When choosing a coating, the possibility of ingress of solid soil particles into the friction zone is taken into account.…”

Improving the Quality of Friction Surface by Applying Antifriction Materials to Them

“…However, the surfaces of rubbing parts after restoration of diffusion coatings have increased roughness. This contributes to the development of cavitation pitting [11][12][13][14][15][16].…”