Abstract
The mechanism of liquid phase sintering of an Fe-6 wt pct B-48 wt pct Mo alloy was investigated by means of thermal dilatometry, differential thermal analysis (DTA), X-ray diffraction (XRD), and scanning electron microscopy (SEM). A fine composite microstructure of Mo2FeB2 and ferrite was produced from powders of Fe, Mo, and FeB by a reaction sintering process involving two liquid phases. The hard phase Mo2FeB2 is produced in the compact prior to liquid formation initially by the reaction 2Mo+2FeB=Mo2FeB2+Fe and later by the reaction 2Mo+2Fe2B=Mo2FeB2+ 3Fe. Above 1365K, considerable densification results from the initial stage rearrangement of the solid phases (austenite and Mo2FeB2) coexisting with the first formed liquid phase (L1). Another liquid (L2) which forms above 1415K, where Mo2FeB2 is the only coexisting solid phase, is required for complete densification. L2, having a high solubility for Mo2FeB2, provides for solution/reprecipitation processes which characterize the intermediate stage of liquid phase sintering. The effective separation of the initial and intermediate stages by L1 and L2 is considered essential for the control of the sintered microstructure of the ternary alloy.
Similar content being viewed by others
References
W. Reiger, H. Nowotny, and F. Benesovsky:Monatsh. Chem., 1964, vol. 95, pp. 1502–03.
T. Ide, M. Fukumori, K. Takagi, T. Watanabe, and Y. Kondo:Proc., 1986 Int. Powder Metall. Conf. and Exhib., Düsseldorf, 1986, pp. 1073–76.
K. Takagi, T. Watanabe, T. Ando, and Y. Kondo:Int. J. Powder Metall., 1986, vol. 22, pp. 91–96.
Y. Kondo, T. Watanabe, T. Ide, and K. Takagi:J. Adhesion Soc. Japan, 1985, vol. 21, pp. 18–23.
R. M. German, K.-S. Hwang, and D. S. Madan:Powder Metall. Int., 1987, vol. 19, pp. 15–18.
M. Hansen and K. Anderko:Constitution of Binary Alloys, McGraw-Hill, New York, NY, 1958.
R. M. German:Liquid Phase Sintering, Plenum Press, New York, NY, 1985.
T. Ide, K. Nakano, and K. Takagi:J. Jap. Soc. Powder and Powder Metall., in press.
J. A. Lund and S. R. Bala:Modern Developments in Powder Metallurgy, H. H. Hausner and W. E. Smith, eds., Metal Powder Industries Federation, Princeton, NJ, 1974, vol. 6, pp. 409–21.
H. S. Cannon and F. V. Lenel:Plansee Proceedings, F. Benesovsky, ed., Metallwerk, Plansee, Reutte, Austria, 1953, pp. 106–21.
V. N. Eremenko, Y. V. Naidich, and I. A. Lavrinenko:Liquid Phase Sintering, Consultants Bureau, New York, NY, 1970.
W. J. Huppmann, W. A. Kaysser, D. N. Yoon, and G. Petzow:Powder Metall. Int., 1979, vol. 11, pp. 50–51.
W. D. Kingery:J. Appl. Phys., 1959, vol. 30, pp. 301–06.
P. E. Busby, M. E. Warga, and C. Wells:Trans. AIME, vol. 197, pp. 1463–68.
M. E. Nicholson:Trans. AIME, 1954, vol. 200, pp. 185–90.
T. B. Cameron and J. E. Morral:Metall. Trans. A, 1986, vol. 17A, pp. 1481–83.
Author information
Authors and Affiliations
Additional information
Teiichi Ando, formerly with the Technical Research Laboratory, Toyo Kohan Co., Ltd., is with the Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139.
Rights and permissions
About this article
Cite this article
Ide, T., Ando, T. Reaction sintering of an Fe-6 Wt Pct B-48 Wt Pct Mo alloy in the presence of liquid phases. Metall Trans A 20, 17–24 (1989). https://doi.org/10.1007/BF02647490
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF02647490