| 2004 №02 (03) | 2004 №02 (05) |
The Paton Welding Journal, 2004, #2, 17-24 pages
Effect of primary structure of cast heat-resistant nickel alloys on formation of hot cracks during welding
N.I. Pinchuk1, N.K. Ryazantsev2
1E.O. Paton Electric Welding Institute of the NASU 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.2Kharkov Design Bureau for Engine Construction, Kharkov, Ukraine
Abstract
Effect of primary structure and phase composition on weldability of cast nickel alloys containing up to 6 % aluminium is considered. The positive effect of two-phase primary structure containing an increased amount of aluminium eutectic with the gamma-phase (Ni3Al) is shown. Investigation data on alloy JS6-U of conventional casting and oriented solidification, as well as on new alloy LJ1-I, used for manufacture of welded gas turbine rotors are presented.
Keywords: nickel alloy, fusion welding, hot cracks, pri¬mary structure, crystalline grain boundaries, eutectic, second phase
References
1. Rovensky, I.L., Pinchuk, N.I., Yushchenko, K.A. (2001) Development of all-welded high-temperature turbine rotor for augmented turbopiston engines. Dvigatelestroenie, 3, 11−13.2. Medovar, B.I. (1966) Welding of refractory austenitic steels and alloys. Moscow: Mashinostroenie.
3. Eniskevich, V. (1976) Joining of parts from refractory alloys. In: Refractory alloys. Moscow: Metallurgiya.
4. Stephenson, N., Symonds, C.H., Thorneycroft, D.R. (1962) Welding of nickel alloys in heavy sections for power generating plant. British Welding J., 9(5), 301−310.
5. Medovar, B.I., Chekotilo, L.V., Pinchuk, N.I. et al. (1964) Prevention of near-weld hot crack formation in arc welding of refractory alloy EI437B. Aviats. Promyshlennost, 5, 77−79.
6. Santella, M.L., David, S.A. (1986) A study of heat-affected zone cracking in Fe-containing Ni3Al alloys. Welding J., 5, 129−137.
7. Shorshorov, M.Kh., Klebanov, G.N., Gushchin, L.S. (1956) Study of kinetics of grain growth and changes in structure and mechanical properties of low-alloy steel in the weld zone. Svarochn. Proizvodstvo, 9, 1−4.
8. Medovar, B.I., Pinchuk, N.I., Chekotilo, L.V. (1971) Austenitic-boride steels and alloys for welded structures. Kiev: Naukova Dumka.
9. Sorokin, L.I., Tupikin, V.I. (1985) Classification of refrac¬tory nickel alloys on the basis of their crack resistance. Avtomatich. Svarka, 5, 23−25.
10. Bulatov, Yu.V., Loseva, G.I. (1977) Segregation of niobium and aluminium in nickel alloy welds. Svarochn. Proizvodstvo, 5, 6−7.
11. Schmidtman, E., Eckel, W. (1983) An investigation into the tendency to hot cracking when XIONiCrAlTi 32 20 material is manual arc welded using electrodes of the X15NiCrNb 32 21 type of varying composition. Welding and Cutting, 6, 92−94.
12. Bachle, E., Lesou, J. (1981) Quality of refractory alloy castings. In: Refractory steels for gas turbines. Moscow: Metallurgiya.
13. van Maaren, P.W. (1984) Polarisation and scanning electron microscopic investigation of corrosion and oxidation layers in IN 939 stator blades in a natural gas-driven turbine. Practical Metallography, 21, 215−240.
14. Adam, P. (1981) Welding of high-strength alloys for gas turbines. In: Refractory steels for gas turbines. Moscow: Metallurgiya.
15. Owczarski, W.A., Duwall, D.S., Sillivan, C.P. (1962) A model for affected zone cracking in nickel-base superalloys. Welding J., 45(4), 145−155.
16. Pinchuk, N.I., Ryazantsev, N.K., Rovensky, I.L. (2002) Welded joints of austenitic steel 25Cr-20Ni-2Si in augmented turbopiston engines. The Paton Welding J., 6, 13−18.
17. Zimina, L.N. (1977) Weldable refractory nickel alloys and principles of their alloying. Metallovedenie i Term. Obrab. Materialov, 11, 2−7.
18. Yushchenko, K.A., Pinchuk, N.I., Nakonechny, A.A. et al. (1985) Investigation of weldability of cast refractory nickel alloys with 6 % aluminium. Avtomatich. Svarka, 10, 18−24.
19. Kotov, V.F., Makhneva, G.A., Shvarts, V.I. et al. Weldable blade alloy. Pat. 8163 Ukraine. Int. Cl. C 22 C 19/03. Publ. 16.12.95.
20. (2001) High-temperature welded rotors of gas turbines. Avtomatich. Svarka, 4, 32.