Abstract
The local compositional order and dislocation structure of grain boundaries in Ni3Al, with and without boron, were examined using electron microscopy techniques. Lattice imaging studies showed that small angle twist, tilt and mixed boundaries and large angle (near Σ = 5) [001] twist boundaries are ordered up to very close to the interface plane. A compositionally disordered region ~1.5 nm thick is present in the vicinity of a large angle general boundary in boron-doped Ni3Al, while similar boundaries in boron-free material are ordered. Image simulations were performed and it was shown that the experimental observations of a locally disordered region cannot be explained as being an artifact. Dislocations with Burgers vectors that correspond to anti-phase boundary (APB)-coupled superpartials were found in small angle [001] twist boundaries in both boron-free and boron-doped Ni3Al and a small angle [011] tilt boundary in boron-doped Ni3Al. The APB energies determined from the dissociation of the boundary dislocations were smaller than reported for bulk Ni3Al. For small angle twist boundaries the presence of boron reduced the APB energy at the interface until it approached zero.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Aoki, K. and Izumi, O. (1979) ‘Improvement in Room Temperature Ductility of the L12-Type Intermetallic Compound Ni3Al by Boron Addition’ Trans. J. Japan Inst. Metals 43, 1190–1196
Liu, C. T., White, C. L. and Horton, J. A. (1985) ‘Effect of Boron on Grain Boundaries in Ni3Al’, Acta met. 33, 213–229
Horton, J. A. and Miller, M. K. (1987) ‘Atom Probe Analysis of Grain Boundaries in Rapidly Solidified Ni3Al’, Acta met. 35, 133–141
White, C. L., Padgett, R. A., Liu, C. T. and Yalisove, S. M. (1984) Scripta met. 18, 1417–1420
Messmer, R. P. and Briant, C. L. (1982) ‘The Role of Chemical Bonding in Grain Boundary Embrittlement’, Acta met. 30, 457–467
Schulson, E. M., Weihs, T. P., Veins, P. V. and Baker, I. (1985) ‘The Effect of Grain Size on the Yield Strength of Ni3Al’, Acta met. 33, 1587–1591
Schulson, E. M., Weihs, T. P., Baker, I., Frost, H. J. and Horton, J. A. (1986) ‘Grain Boundary Accommodation of Slip in Ni3Al Containing Boron’, Acta met. 34, 1395–1399
King, A. H. and Yoo, M. H., (1987) ‘On the Availability of Dislocation Reactions at Grain Boundaries in Cubic Ordered Alloys’, Scripta met. 21, 1115–1119
Sieloff, D. D., Brenner, S. S. and Burke, M. G., (1987) ‘FIM/Atom Probe Studies of B-Doped and Alloyed Ni3Al’, MRS Symposium 81, 87–97
Baker, I., Schulson, E. M. and Michael, J. R. (1988) ‘The Effect of Boron on the Chemistry of Grain Boundaries in Stoichiometric Ni3Al’, Phil. Mag. B57, 379–385
George, E. P., Liu, C. T. and Padgett, R. A. (1989) ‘Comparison of Grain Boundary Compositions in B-Doped and B-Free Ni3Al’, Scripta met. 23, 979–982
Mackenzie, R. A. D. and Sass, S. L. (1988) ‘Direct Observation of the Compositional Disordering of Ni3Al in the Vicinity of Grain Boundaries Using High Resolution Electron Microscopy Techniques’, Scripta met. 22, 1807–1812
Krzanowski, J. E. (1989) ‘Nickel Enrichment Near Grain Boundaries in Chill Cast Ni3Al Alloys and Its Relation to Grain Boundary Cohesive Strength’, Scripta met 23, 1219–1224
Mills, M. (1989) ‘Determination of the Compositional Ordering at Grain Boundaries in Boron-Doped Ni3Al’, Scripta met., 23, 2061–2066
Baker, I., Schulson, E. M., Michael, J. R. and Pennycook, S. J., (1990) ‘The Effects of Both Deviation From Stoichiometry and Boron on Grain Boundaries in Ni3Al’, Phil. Mag. B62, 659–676
Kung, H., Rasmussen, D. R. and Sass, S. L. (1991) ‘Grain Boundaries in Ni3Al, Part I: The Local Compositional Order, and Part II: The Dislocation Structure of Small Angle Boundaries’, Acta met. To be published (1991)
Kilaas, R. (1987) ‘Interactive Simulation of High Resolution Electron Micrographs, Proc. 45th Annual Meeting EMSA, 66–67
Marcinkowski, M. J. (1968) ‘Theory of Grain Boundaries in Ordered Alloys’, Phil. Mag. 17, 159–168
Czernichow, J., Gudas, J. P., Marcinkowski, M. J. and Tseng, Wen Feng (1971) ‘Twist Boundaries in Ordered Alloys’, Met. Trans., 2, 2185–2188x
Douin, J., Veyssiere, P. and Beauchamp, P. (1986) ‘Dislocation Line Stability in Ni3Al’, Phil. Mag. A, 54, 375–393
Veyssiere, P., Yoo, M. H., Horton, J. A. and Liu, C. T., (1989) ‘Temperature Effect on Superdislocation Dissociation on a Cube Plane in Ni3Al’, Phil. Mag. Let. 59, 61–68
Mackenzie, R. A. D., Vaudin, M. D. and Sass, S. L. (1988) ‘Grain Boundary Structure in Ni3Al’, Proc. 46th Annual Meeting EMSA, 602–603
Buis, A., Tichelaar, F. D. and Schapink, F. W. (1989) ‘Transmission Electron Microscopy Observations on a Small Angle Symmetrical Tilt Boundary in B2-Ordered Fe3Al’, Phil. Mag. A, 59, 861–871
Kruisman, J. J., Vitek, V. and De Hosson, J. Th. M. (1988) ‘Atomic Structure of Stoichiometric and Non-Stoichiometric A3B Compounds with L12 Structure’, Acta met. 36, 2729–2741
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 1992 Springer Science+Business Media Dordrecht
About this chapter
Cite this chapter
Kung, H., Rasmussen, D.R., Sass, S.L. (1992). The Local Compositional Order and Dislocation Structure of Grain Boundaries in Ni3Al. In: Liu, C.T., Cahn, R.W., Sauthoff, G. (eds) Ordered Intermetallics — Physical Metallurgy and Mechanical Behaviour. NATO ASI Series, vol 213. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-2534-5_23
Download citation
DOI: https://doi.org/10.1007/978-94-011-2534-5_23
Publisher Name: Springer, Dordrecht
Print ISBN: 978-94-010-5119-4
Online ISBN: 978-94-011-2534-5
eBook Packages: Springer Book Archive