Navoi branch of the Academy of Sciences of Uzbekistan (Navoi, Uzbekistan):

A. A. Zhumaev, Postgraduate Student, E-mail: ahmadjon_jumayev@mail.ru

Institute of General and Inorganic Chemistry of the Academy of Sciences of Uzbekistan (Tashkent, Uzbekistan):
Yu. N. Mansurov, Dr. Eng., Director, Prof. of the Tashkent State Transport University, E-mail: yulbarsmans@gmail.com

Samarkand State Institute of Architecture and Civil Engineering (Samarkand, Uzbekistan):
D. D. Mamatkulov, Dr. Eng., Prof.

Navoi Machine-Building Plant (Navoi, Uzbekistan):
G. D. Ulugov, Head of the Central Plant Laboratory

The mining industry of Uzbekistan uses hundreds of tons of white wear-resistant cast iron monthly for the manufacture of parts for machinery and equipment that extract natural raw materials. Only the Production Association Navoi Machine-Building Plant (PO «NMZ») monthly produces cast parts from wear-resistant high-chromium alloyed white cast iron with a volume of more than 120 tons per month. Most of the parts are made for rock crushers; their wear during work in mines shortens the service life of machinery and equipment. Parts of foreign equipment: dredge pumps, lining of grinding mills, hydraulic transport and others are made of white cast iron, highly alloyed with chromium, nickel, copper, titanium and other chemical elements. The annual import into the republic of parts made of cast irons of complex chemical composition requires signifi cant costs. In order to save money by refusing to import parts, a domestic wear-resistant white cast iron of grade 280Kh29NL was developed, from which rubbing parts, operating under wear conditions in mines, for mining equipment are cast in the foundry of the Navoi Machine-Building Plant. Considering that ferroalloys for the production of cast iron are also imported, the cost savings in the production of mining equipment parts instead of worn-out ones is insignificant. The purpose of this work is to optimize the composition of highly alloyed wear-resistant white cast iron for its replacement in industry with an economically alloyed analogue, as well as to improve the structure of the composition-optimized white wear-resistant cast iron to obtain the required level of performance properties of parts operating under friction and wear conditions. For this, phase transformations, the structure and properties of white cast iron, and the conditions for casting parts were studied. Based on the research results, recommendations were developed for economical alloying and casting technology for friction and wear parts.

1. GOST 7293–85. Spheroidal graphite iron for castings. Grades. Introduced: 01.01.1987.
2. GOST 23.208–79. Ensuring of wear resistance of products. Wear resistance testing of materials by friction against loosely fixed abrasive particles. Introduced: 01.03.1981.
3. Garber M. E. Wear-resistant white cast irons: properties, structure, technology, operation. Moscow: Mashinostroenie, 2010. 280 p.
4. Konar B., Kim J., Jung I. Critical Systematic Evaluation and Thermodynamic Optimization of the Fe–RE System: RE = La, Ce, Pr, Nd and Sm. Journal Phase Equilibria and Diffusion. 2016. Vol. 37, Iss. 4. pp. 438–458.
5. Kolokoltsev V. M., Petrochenko E. V., Molochkova O. S. Influence of boron modification and cooling conditions during solidification on structural and phase state of heat- and wear-resistant white cast iron. CIS Iron and Steel Review. 2018. Vol. 15. pp. 11–15.
6. Ali K., Ghosh P. S., Arya A. A DFT study of structural, elastic and lattice dynamical properties of Fe₂Zr and FeZr2 intermetallics. Journal Alloys Compd. 2017. Vol. 723. pp. 611–619.
7. Mukhamedov B. O., Ponomareva A. V., Abrikosov I. A. Spinodal decomposition in ternary Fe–Cr–Co system. Journal Alloys Compd. 2017. Vol. 695. pp. 250–256.
8. Karantzalis A. E., Lekatou A., Kapoglou A., Mavros H., Dracopoulos V. Phase Transformations and Microstructucal Observations During Subcritical Heat Treatments of a High-Chromium Cast Iron. Journal of Materials Engineering and Performance. 2012. Vol. 21, Iss. 6. pp. 1030–1039.
9. Sain P. K., Sharma C. P., Bhargava A. K. Microstructure, Aspects of a Newly Developed, Low Cost, Corrosion-Resistant White Cast Iron. Journal Metallurgical and Materials Transactions A. 2013. Vol. 44. pp. 1665–1671.
10. Yoganandh J., Natarjan S., Kumaresh S. P. Babu. Erosive Wear Behavior of Nickel-Based High Alloy White Cast Iron Under Mining Conditions Using Orthogonal Array. Journal of Materials Engineering and Performance. 2013. Vol. 22, Iss. 9. pp. 2534–2540.
11. Petrochenko E. V. Interconnection, between chemical composition, structure and properties of complex-alloyed white irons in a cast condition. Izvestiya vysshikh uchebnykh zavedeniy. Chernaya metallurgiya. 2012. No. 3. pp. 51–55.
12. Kolokoltsev V. M., Petrochenko E. V. Structure Feature And Properties Of High-Alloy White Irons. Vestnik Magnitogorskogo gosudarstvennogo tekhnicheskogo universiteta imeni G. I. Nosova. 2013. No. 5, Iss. 45. pp. 3–8.
13. Ponomareva A. V., Ruban A. V., Mukhamedov B. O., Abrikosov I. A. Effect of multicomponent alloying with Ni, Mn and Mo on phase stability of bcc Fe–Cr alloys. Acta Materialia. 2018. Vol. 150. pp. 117–129.
14. Kabliman E., Blaha P., Schwarz K., Peil O. E., Ruban A. V., Johansson B. Configurational thermodynamics of the Fe–Cr σ-phase. Physical Review B. 84. 2011. Article ID 184206.
15. Naraghi R., Selleby M., Agren J. Thermodynamics of stable and metastable structures in Fe–C system. Calphad. 2014. Vol. 46. pp. 148–158.
16. Kolokoltsev V. M., Petrochenko E. V., Molochkova O.S. Al influence on the phase composition, structure and properties of heat- and wear-resistant cast iron of Cr–Mn–Ni–Ti system. Chernye Metally. 2018. No. 7. pp. 6–11.
17. Abrikosov I. A., Ponomareva A. V., Steneteg P., Barannikova S. A., Alling B. Recent progress in simulations of the paramagnetic state of magnetic materials. Current Opinion Solid State Materials Science. 2016. Vol. 20. pp. 85–106.
18. Kravchenko N. S., Revinskaya О. G. Methods for processing measurement results and assessing errors in an educational laboratory practice. Tomsk, 2011. 173 p.
19. Yang Yi., Tan L., Bei H., Busby J. T. Thermodynamic modeling and experimental study of the Fe–Cr–Zr system. Journal Nucl. Mater. 2013. Vol. 441, Iss. 1-5. pp. 190–202.