| 2006 №11 (07) | 2006 №11 (09) |
The Paton Welding Journal, 2006, #11, 35-38 pages
Effect of heat treatment on structure of amorphised detonation Fe-B coatings
E.A. Astakhov, Yu.S. Borisov, G.S. Kaplina, N.N. Kokorina, Z.G. Ipatova, O.F. Chernyakov
E.O. Paton Electric Welding Institute of the NASU. 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.Abstract
The effect of heat treatment (HT) in a range of 200–650 °C on the process of crystallisation of the amorphous phase (AP) in detonation coatings deposited from powders of amorphising Fe-B alloy with a particle size of < 40 and 40–63 mm was investigated. It is established that the AP content of a coating deposited from a fine powder is 32 vol.%, and that of a coating deposited from the powder with a particle size of 40–63 mm is 57 vol.%. Heating to 500 °C leads to complete crystallisation of AP in both cases. Microstructure of coatings was investigated, and they were tested to gas-abrasive wear resistance after HT at different temperatures. Maximal increase in wear resistance (by 35-40 %) was achieved at a structural state of the coatings corresponding to crystallisation (~3 % AP).
Keywords: detonation spraying, amorphous phase, nanocrystalline structure, crystallisation, gas-abrasive wear resistance
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