Influence of the composition of the cumulative lattice during thermal diffusion chromiing on the depth of the diffusion layer-Reference-Cited by-同舟云学术

Influence of the composition of the cumulative lattice during thermal diffusion chromiing on the depth of the diffusion layer

Published:2023-08-21 Issue:7 Volume:79 Page:596-603
ISSN:2619-0753
Container-title:Ferrous Metallurgy. Bulletin of Scientific , Technical and Economic Information
language:
Short-container-title:Černaâ metallurgiâ. Bûlletenʹ naučno-tehničeskoj informacii

Author:

Shaburova N. A.¹

Affiliation:

1. South Ural State University (National Research University)

Abstract

Presents the results of experiments on improving the technology of thermal diffusion chromium plating of structural steels through the use of an internal emission field created in the technological backfill during heating. To create a field in the separating part of the technological backfill, aluminum oxide was completely replaced by mixtures of two compositions: a mixture of scheelite (CaWO4) and serpentine (Mg3Si2O7); a mixture of scheelite (CaWO4), serpentine (Mg3Si2O7), MgO, dicalcium silicate (γ-2•CaO•SiO2). The choice of these materials was based on the results of preliminary experiments on measuring the thermionic current in them. Saturation of samples of steel 35CrNi2-3 with chromium was carried out at a temperature of 1000°C for 24 hours. For both variants of technological fillings, the ab-sence of sintering and good knockout of parts were noted. The chemical composition of the diffusion layer on metal samples was controlled using a JEOL JSM-6460LV universal scanning (scanning) electron microscope. The micro-hardness of the coatings was measured using an FM-800 microhardness tester. The results show that the additional use of cumulative lattices of nickel and nichrome for thermal diffusion chromium plating provides an increase in the depth of chromium diffusion by 1.5 times when saturated in the backfill of the same composition. In this case, the lattice material has little effect on the depth of chromium diffusion, but it influences the intensity of surface microalloying with nickel. The electron yield work of nichrome X20H80, equal to 4.5 eV, has been determined. It was found that the hardness of the diffusion layers formed on the surface correlates with the content of chromium and nickel in them. The hardness of the chrome layer is 790±10 HV and 820±10 HV, using nickel and nichrome cumulative lattices, respective-ly. In the case of saturation without grids, the hardness is 50 and 20 HV respectively lower.

Publisher

South Ural State University

Subject

General Medicine

Reference14 articles.

1. Basalai I. A. Corrosion resistance of carbon steels with complex thermal diffusion coatings in technological environments of potash production. Gornaya mekhanika i mashinostroenie, 2011, no. 1, pp. 73–77. (In Russ.).

2. Voroshnin L. G., Lyakhovich L. S., Lovshenko F. G., Protasevich G. F. Khimiko-termicheskaya obrabotka metallokeramicheskikh materialov [Chemical-thermal treatment of cermet materials]. Moscow: Nauka i tekhnika, 1977, 272 p. (In Russ.).

3. Popova N. V. Tekhnologiya diffuzionnogo nasyshcheniya khromom i nikelem poverkhnostei poroshkovykh ma-terialov na osnove zheleza [Technology of diffusion saturation with chromium and nickel of the surfaces of powder materials based on iron]. Vnedrenie rezul’tatov innovatsionnykh razrabotok: problemy i perspektivy: sb. statei Mezhdunarodnoi nauchno-prakticheskoi konferentsii. 3 ch. [Implementation of the results of innovative developments: problems and prospects: coll. articles of the International Scientific and Practical Conference. 3 part]. Ufa: MTsII Omega Science, 2016, pp. 148–50. (In Russ.).

4. Shaburova N. A., Pashkeev I. Yu. Effect of the joint saturation conditions of steel with chromium and nickel on the diffusion layer depth. Chernaya metallurgiya. Byulleten’ nauchno-tekhnicheskoi i ekonomicheskoi informatsii = Ferrous metallurgy. Bulletin of scientific, technical and economic information, 2022, vol. 78, no. 6, pp. 542–548. (In Russ.). DOI: 10.32339/0135-5910-2022-6-542-548.

5. Shaburova N. A., Pashkeev I. Yu. Influence of the technology of thermal diffusion chroming on the depth of the diffusion layer. Chernaya metallurgiya. Byulleten’ nauchno-tekhnicheskoi i ekonomicheskoi informatsii = Ferrous metallurgy. Bulletin of scientific, technical and economic information, 2023. vol. 79, no. 1, pp. 63–70. (In Russ.). DOI: 10.32339/0135-5910-2023-1-63-70.