Carburization of Fe-Ni-Cr alloys at high temperatures

• Autorzy: Ul-Hamid A. , Tawancy H.M. , Al-Jaroudi S.S. , Mohammed A.I. , Abbas N.M.
• Języki publikacji: EN

Abstrakty

EN

A large number of radiant tubes belonging to an ethylene furnace of a petrochemical plant failed during service. All tubes exhibited severe carburization while some of them lost their structural integrity and sagged. The tube material was based on Fe-Ni- Cr alloy system with three varying compositions. Scanning electron microscopy and energy dispersive X-ray spectroscopy were used to characterize the microstructure and elemental composition of the tubes material. Microhardness testing was performed to determine their mechanical strength. Experimental results indicated that sagged tubes exhibited higher degree of carburization compared to the other tubes. Microstructure of these tubes also revealed coarser Cr-carbide precipitation and continuous carbide lattice at austenite grain boundaries. It was concluded that exposure to excessive temperature during service was responsible for the degradation of all tube materials. Based upon above results, it was recommended that a better control of furnace temperature should be employed in order to avoid overheating during service.

Słowa kluczowe

EN

Fe-Ni-Cr alloy; carburisation; SEM; scanning electron spectroscopy; furnace tube; high temperature

PL

nawęglanie; elektronowa mikroskopia skaningowa; płomienica; temperatura wysoka; stop Fe-Ni-Cr; stop żelaza-niklu-chromu

• Wydawca: De Gruyter
• Czasopismo: Materials Science Poland
• Rocznik: 2006
• Tom: Vol. 24, No. 2/1
• Strony: 319--331
• Opis fizyczny: Bibliogr. 6 poz.

Twórcy

autor

Ul-Hamid A.

autor

Tawancy H.M.

autor

Al-Jaroudi S.S.

autor

Mohammed A.I.

autor

Abbas N.M.

• Center for Engineering Research, Research Institute, King Fahd University of Petroleum & Minerals, P. O. Box 1073, Saudi Arabia,

Bibliografia

• [1] BLACKBURN J., [in:] Carburization in High Temperature Process Plant Materials, Colloquium Proceedings Coordinated by J. Norton, Commission of the European Communities, Luxembourg, Report No. EUR 7773, 1981, 7.
• [2] NACE Standard TM 0498-98-Item No. 21235.
• [3] LAI G. Y., [in:] High Temperature Corrosion in Energy Systems, M. F. Rothman (Ed.), TMS-AIME, Warrendale, Pennsylvania, 1985, 551.
• [4] ASM Metals Handbook, Properties and selection of metals, Vol. 1, 8th Edition, 1977.
• [5] TAWANCY H.M., ABBAS N.M., J. Mater. Sci., 26 (1992), 1061.
• [6] SCHNAAS A., GRABKE H.J., Oxidation of Metals, 12 (1978), 387.