Browse > Article
http://dx.doi.org/10.5228/KSPP.2008.17.7.523

Electron Beam Weld ability of Alloy 718 Nozzle for Jet Propulsion Component  

Lee, C.H. (동의대학교 신소재공학과)
Kim, J.H. (한국기계연구원 부설 재료연구소)
Hong, J.K. (한국기계연구원 부설 재료연구소)
Yeom, J.T. (한국기계연구원 부설 재료연구소)
Yoon, J.W. (동의대학교 신소재공학과)
Park, N.K. (한국기계연구원 부설 재료연구소)
Publication Information
Transactions of Materials Processing / v.17, no.7, 2008 , pp. 523-527 More about this Journal
Abstract
In this study, mechanical properties of Alloy 718 welded after forgings for jet propulsion component was investigated. Hot-forged and machined work-pieces($230mm\times70mm\times15mm$) which have different grain sizes are welded by electron beam welding technique. After welding, the components were solution heat-treated and aged. Samples were sectioned to analyze the microstructural evolution and formation of micro-crack. It was found that HAZ grain boundary liquation crack generally initiates in the coarse grains rather than the fine grains. Needle-like phases with high Nb contents were found at the outer part near the base metal. Vickers hardness and tensile tests were carried out at room temperature and at $649^{\circ}C$. The tensile properties of electron beam welding specimens exhibited around 100MPa and 10% decrease in strength and elongation, respectively.
Keywords
Superalloy; Alloy718; Electron Beam Welding; Microstructures; Mechanical Properties;
Citations & Related Records
연도 인용수 순위
  • Reference
1 T. E. Kilgren, C. E. Lacet, 1946, The control of weld got cracking in nickel chromium iron alloys, Welding Journal, Vol. 25, pp. 11
2 S. Azadian, L-Y. Wei, R. Warren, 2004, Delta phase precipitation in Inconel 718, Mater. Character. Vol. 53 pp. 7-16   DOI   ScienceOn
3 J. W. Brooks, P. J. Bridges, 1988, Metallurgical Stability of Inconel Alloy 718, Sixth International Symposium on Superalloys, held in Champion, PA, September pp. 18-22, pp. 33-42
4 Chen, W., Chaturvedi, M.C., Richards, N.L., 2001. Effect of boron segregation at grain boundaries on heat affected zone cracking in wrought Inconel 718. Metal. Trans. A 32, 931-939   DOI
5 W. D. Cao, R. Kennedy, 2004, Superalloys, pp. 91-99
6 S. C. Ermst, W.A. Baeslack III, J. C. Lippold, 1989, Welding Journal. pp. 418-430
7 T. F. Bower, H. D. Brody, M. C. Flemings, 1966 AIME Met. Soc. Trans. Vol. 236, pp. 624-634
8 N. L. Richard, X. Huang, 1991, Mater, Character. Vol. 28. pp. 11-13
9 M. J. Donachie, S. J. Donachie, Superalloys A technical guide 2nd edition. ASM international
10 J. F. Barker et al., 1970, J. Met. January, pp.31