Effect of Heat Treatment on the Creep Properties of Ti-22Al-27Nb/TiB Composite

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A TiB particulate-reinforced Ti-22Al-27Nb (mol%) alloy, based on the orthorhombic intermetallic phase, was prepared using gas atomization powder metallurgy method. In the as-atomized condition, extremely fine TiB particulates of less than 1-μm diameter and 5-μm length were dispersed in the matrix. After annealing heat treatment (heat treated at 1423 K with subsequent furnace cooling), this composite exhibited a lamellar matrix microstructure and showed better creep properties than a composite produced using conventional ingot metallurgy method, with coarse TiB particulates of 5-μm diameter and 40-μm length. Coarsening of the matrix microstructure and growth of TiB particulates occurred after annealing heat treatment at higher temperature (ca. 1473 K). Creep-resistance improvement was also observed, which seemed to be mainly attribute to the effect of the matrix microstructure. From measurements of stress components and activation energy, all composites showed an identical creep mechanism: dislocation-controlled creep.

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Periodical:

Key Engineering Materials (Volumes 345-346)

Edited by:

S.W. Nam, Y.W. Chang, S.B. Lee and N.J. Kim

Pages:

545-548

Citation:

S. Emura and M. Hagiwara, "Effect of Heat Treatment on the Creep Properties of Ti-22Al-27Nb/TiB Composite", Key Engineering Materials, Vols. 345-346, pp. 545-548, 2007

Online since:

August 2007

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$38.00

[1] D. Banerjee, A.K. Gogia, T.K. Nandy and V.A. Joshi: Acta Metall. Vol. 36 (1988), p.871.

[2] R.G. Rowe, in: Microstructure/Property Relationships in Titanium Aluminides and Alloys, edited by Y-W. Kim and R.R. Boyer, TMS, Warrendale, USA, (1991) , p.387.

[3] J. Kumpfert and C. Leyens, in: Structural Intermetallics 1997, edited by M.V. Nathal, R. Darolia, C.T. Liu, P.L. Martin, D.B. Miracle, R. Wagner and M. Yamaguchi, TMS, Warrendale, USA, (1997), p.895.

[4] R.G. Rowe, D.G. Konitzer, A.P. Woodfield and J.C. Chesnutt, in: High Temperature Aluminides & Intermetallics IV, edited by L.A. Johnson, D.P. Pope and J.O. Stiegler, MRS, Pittsburgh, USA, (1991), p.703.

[5] S. Emura and M. Hagiwara, in: Titanium 99 Science and Technology, edited by I.V. Gorynin and S.S. Ushkov, CRISM "Prometey, St. Petersburg, Russia, (2000), p.298.

[6] T. Saito, T. Furuta and T. Yamaguchi, in: Metallurgy and Technology of Practical Titanium Alloys, edited by S. Fujishiro, D. Eylon and T. Kishi, TMS, Warrendale, USA, (1994), p.351.

[7] S. Emura, S.J. Yang and M. Hagiwara: Metall. Trans. A. Vol. 35A (2004), p.2971.

[8] S.J. Yang, S. Emura, S.W. Nam, M. Hagiwara, H.S. Jeon and S.B. Yoon: Materials Letters Vol. 58 (2004), p.3187.

[9] C.J. Boehlert and D.B. Miracle: Metall. Trans. A. Vol. 30A (1999), p.2349.

[10] T.K. Nandy, R.S. Mishra, A.K. Gogia and D. Banerjee: Scripta Metall. Vol. 32 (1995), p.851.

[11] T.K. Nandy, and D. Banerjee: Intermetallics Vol. 8 (2000), p.915.