The Paton Welding Journal, 2009, №01



2009 №01 (12)

2009 №01 (02)

---

TPWJ, 2009, #1, 2-5 pages

EVALUATION OF SUSCEPTIBILITY OF WELDED JOINTS OF HEAT-RESISTANT CHROMIUM MARTENSITIC STEEL TO CRACKING AT HEAT TREATMENT

Journal                    The Paton Welding Journal
Publisher                 International Association «Welding»
ISSN                       0957-798X (print)
Issue                       № 1, 2009 (January)
Pages                       2-5
 
 
Authors
V.Yu. SKULSKY, A.K. TSARYUK and S.I. MORAVETSKY
E.O. Paton Electric Welding Institute, NASU, Kiev, Ukraine
 
 
Abstract
The mechanisms of cracking of welded joints in tempering used to relieve stresses are considered. It has been found that welded joints on steel 10Kh9MFB with a homogeneous martensitic structure are insensitive to temper cracking. Formation of δ-ferrite in the martensitic structure may lead to cracking of the weld metal. Cracks form in tempering in the range of about 450-550 °C as a result of concentrated deformation within the zone of soft ferrite interlayers in development of secondary hardening of the martensitic matrix. A probable cause of hardening is precipitation of chromium carbide M₇C₃.
 
 
Keywords: arc welding, martensitic steel, welded joints, heat treatment, dispersion hardening, soft interlayers, temper cracking
 
 
Received:                17.09.08
Published:                28.01.09
 
 
References
1. Zemzin, V.N., Shron, R.Z. (1978) Heat treatment and properties of welded joints. Moscow: Mashinostroenie.
2. Nawrocki, G.J. (2001) Stress-relief cracking of a ferritic alloy steel. IIW Doc. IX-2001-01.
3. Boniszewski, T., Eaton, N.F. (1969) Electron fractography of weld-reheat cracking in CrMoV steel. Metal Sci. J., 3, 103-110.
4. Gotoh, A., Nakagawa, T., Hatano, H. et al. (1999) The effects of vanadium on carbide precipitation in 11/4-3 % Cr-Mo steel weld metals. IIW Doc. IX-708-99.
5. Lundin, C.D., Khan, K.K. (1996) Fundamental studies of the metallurgical causes and mitigation of reheat cracking in 11/4 Cr-1/2 Mo and 21/4 Cr-1 Mo steels. WRC Bulletin, 409, 117.
6. Tamaki, K., Suzuki, J., Nakaseko, Y. (1980) Effect of molybdenum carbide on reheat cracking sensitivity of Cr-Mo steels. IIW Doc. IX-1159-80.
7. Tamaki, K., Suzuki, J., Tajiri, M. (1984) Effect of vanadium and titanium on reheat cracking sensitivity. Transact. of JWS, 154, 17-24.
8. Tamaki, K., Suzuki, J. (1983) Effect of chromium and molybdenum on reheat cracking sensitivity of steels. Ibid., 14(2), 123-127.
9. Tamaki, K., Suzuki, J. (1983) Reheat cracking test on high strength steels by a modified implant test. Ibid., 14(2), 117-122.
10. Tamaki, K., Suzuki, J., Nakaseko, Y. et al. (1984) Effect of carbides on reheat cracking sensitivity (Study on reheat cracking of Cr-Mo steels: Report 3). Ibid., 15(1), 8-16.
11. Tamaki, K., Suzuki, J., Li, M.-L. (1993) Influence of vanadium carbide on reheat cracking of Cr-Mo steels – study on reheat cracking of Cr-Mo steels: Report 10. Ibid., 24(2), 87-93.
12. Nawrocki, J.G., Dupont, J.N., Robino, C.V. et al. (2000) The stress-relief cracking susceptibility of a new ferritic steel. Pt 1: Single-pass heat affected zone simulation. Welding J., 79(12), 355-362.
13. Tamaki, K., Suzuki, J., Tate, H. (1988) Combined influence of sulfur and manganese on reheat cracking of Cr-Mo steels. Transact. of JWS, 19(1), 46-52.
14. Tamaki, K., Suzuki, J. (1985) Combined influence of phosphorus, chromium and molybdenum on reheat cracking of steels. Ibid., 16(2), 117-124.
15. Frumin, I.I. (1975) Surfacing in nuclear machine-building. Avtomatich. Svarka, 10, 66-73.
16. Guo, A.-M., Wang, Y.-H., Shen, D.-D. et al. (2003) Influence of phosphorus on the ductility of 2.25Cr1Mo steel. Mat. Sci. and Techn., 19, 1553-1556.
17. Utevsky, L.M., Glikman, E.E., Kark, G.S. (1987) Reversible temper brittleness of steel and iron alloys. Moscow: Metallurgiya.
18. Ito, Y., Nakanishi, M. (1972) Study on stress relief cracking in welded low alloy steels: Report 2. J. JWS, 41(1), 59-64.
19. Sarrak, V.I., Entin, R.I. (1960) Irreversible brittleness in tempering. Metallovedenie i Termich. Obrab. Metallov, 10, 14-19.
20. Demiantsevich, S.V., Zemzin, V.N. (1979) Procedure for evaluation of cracking sensitivity of welded joints in heat treatment. Trudy TsKTI, Issue 169, 22-27.
21. Lanskaya, K.A. (1976) High-chromium heat-resistant steels. Moscow: Metallurgiya.
22. Skulsky, V.Yu. (2006) Influence of alloying of filler material and welded steel on fusion zone structure. The Paton Welding J., 1, 9-15.

---