Article contents
Substitution Behavior in NiAl-A First Principle Prediction Considering Lattice Relaxation
Published online by Cambridge University Press: 10 February 2011
Abstract
The substitution behavior of alloying elements in NiAl is investigated on the basis of electronic structure calculation using the discrete variational Xα cluster method. The method proposed by the authors to predict the substitution behavior is extended to considering lattice relaxation around an alloying atom. A diagram is drawn using the binding energy of clusters when each alloying element occupies either Ni or Al sites as parameters. Two straight lines on the diagram with slope of unity and passing the point of Ni or Al separate the alloying elements into three groups. The elements above the upper line will take Al sites and those below the lower line will take Ni sites regardless of the composition. The substitution behavior of elements in between the two lines will be affected by the alloy composition. The driving force for an element to order on one sublattice is related to its position on the diagram. The effects of temperature, composition and multi-element alloying are discussed. The concepts of site competition and stepped ordering are put forward.
- Type
- Research Article
- Information
- Copyright
- Copyright © Materials Research Society 1999
References
- 3
- Cited by