Obrabotka Metallov 2015 No. 4

ОБРАБОТКА МЕТАЛЛОВ № 4 (69) 2015 78 МАТЕРИАЛОВЕДЕНИЕ Abstract Structure, mechanical properties and wear resistance of hypereutectoid steels with 0.09... 8.97 wt. %. Cu is investigated. Addition of 3 wt. % Cu to the steel is accompanied by an increase in microhardness of pearlite from 380 to 430 HV. At the same time Brinell hardness increases from 340 to 390 HB. A further increase in the concentration of copper has no significant effect on the microhardness of pearlite and the Brinell hardness of the steel. Increasing copper content is the reason for the growth of lamellar pearlite microhardness. Three types of copper-based particles are detected. The first type particles have a size of about 20 nm and are arranged at ferrite intervals of pearlite. The particles of the second type have a size of ~ 1 μm and are arranged at a former grain boundaries of γ-Fe. The particles of the third type have a circular shape and size of ~ 25 μm. Wear resistance of hypereutectoid steel, containing 8.97 wt. % copper, is 3.5 times higher compared to bronze and ~ 23 % in comparison with antifriction cast iron when tested according to the scheme of sliding friction. Mainly, this is due to nanoparticles precipitated in pearlite the copper- based ε-phase. Relative wear resistance of hypereutectoid steel with addition of copper is almost 3 times higher than the durability of bronze in the friction conditions of fixed abrasive particles. The increase in wear resistance in sliding friction conditions, associated with a high content of copper, is due to increases in the volume fraction of cupric nanoparticles. Keywords : hypereutectoid steel, structure, nanoparticles, microhardness, wear resistance. DOI: 10.17212/1994-6309-2015-4-72-79 References 1. Stepanova N.V., Razumakov A.A. The effect of doping with copper and aluminium on structure, mechanical and friction properties of steel. The 8 International Forum on Strategic Technologies (IFOST 2013): proceedings , Mongolia, Ulaanbaatar, 28 June – 1 July 2013, Ulaanbaatar, 2013, vol. 1, pp. 240–242. 2. Golovin E.D., Kuznetsov V.A., Kumar V., Popelyukh P.A., Stepanova N.V. Vliyanie medi na antifriktsionnye svoistva serykh chugunov [Effect of copper addition on friction properties of gray cast iron]. Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) – Metal Working and Material Science , 2012, no. 1 (54), pp. 81–84. 3. Stepanova N.V., RazumakovA.A., Lozhkina Е.А. Structure and mechanical properties of Cu–alloyed cast iron. Applied Mechanics and Materials , 2014, vol. 682, pp. 178–182. doi: 10.4028 /www.scientific.net/AMM.682.178 4. Stepanova N., Razumakov A., Lozhkina E., Zhil’tsov I., Kuznetsov V. Influence of surfactants on the structure and wear resistance of copper alloyed hypereutectoid steel. Advanced Materials Research, 2014, vol. 1040, pp. 53–58. doi: 10.4028 /www.scientific.net/AMR.1040.53 5. Sil’man G.I., Kamynin V.V., Tarasov A.A. Effect of copper on structure formation in cast iron. Metal Science and Heat Treatment , 2003, vol. 45, iss. 7, pp. 254–258. doi: 10.1023/A:1027320116132 6. Prevarskii A. P. Issledovanie sistemy Fe–Cu–Al [Study of Fe-Cu-Al system]. Izvestiya Akademii nauk SSSR. Metally – Russian metallurgy (Metally) , 1971, no. 4, pp. 220–222. (In Russian) 7. Chairuangsri T., Edmonds D.V. The precipitation of copper in abnormal ferrite and pearlite in hyper-eutectoid steels. Acta Materialia , 2000, vol. 48, iss. 15, pp. 3931–3949. doi:10.1016/S1359-6454(00)00176-2 8. Cao L., Wu S., Liu B. On the Cu precipitation behavior in thermo-mechanically embrittlement processed low copper reactor pressure vessel model steel. Materials & Design , 2013, vol. 47, pp. 551–556. doi: 10.1016/j. matdes.2012.12.055 9. Fourlaris G., Baker A.J., Papadimitriou G.D. Microscopic characterisation of ε–Cu interphase precipitation in hypereutectoid Fe–C–Cu alloys. Acta Metallurgica et Materialia , 1995, vol. 43, iss. 7, pp. 2589–2604. doi:10.1016/0956-7151(94)00474-V 10. Chairuangsri T., Edmonds D.V. Abnormal ferrite in hyper-eutectoid steels. Acta Materialia , 2000, vol. 48, iss. 7, pp. 1581–1591. doi: 10.1016/S1359-6454(99)00442-5 11. Malutina I., Bataev I., Lazurenko D., Hokamoto K., EsikovM., Mali V., Jorge JuniorA., BataevA.Amorphous, quasicrystalline and other metastable structures produced at the interface of explosively welded dissimilar materials. The 22nd International Symposium of Metastable, Amorphous and Nanostructured Materials (ISMANAM 2015) . France, Paris, 13–17 July 2015, p. 25. 12. LeMay I., Schetky L. McD., eds. Copper in Iron and Steel . 1st ed. New York, Wiley, 1982. 448 p. ISBN- 10: 0471059137. ISBN-13: 978-0471059134. (Russ. ed.: LeMei I., Shetki L. M.–D. Med’ v chernykh metallakh . Moscow, Metallurgiya publ., 1988. 311 p. ISBN 5-229-00073-2)