Abstmet-The heterogeneous nucleation of martensite at a dislocation is considered using an elasticity model. The dislocation is allowed to have an arbitrary Burgers vector representing, in an approximate manner, the stress field of a pile-up. It is found that an array of roughly 10 dislocations is r
On the thermodynamics of martensite nucleation
β Scribed by A.L. Roitburd
- Publisher
- Elsevier Science
- Year
- 1990
- Tongue
- English
- Weight
- 776 KB
- Volume
- 127
- Category
- Article
- ISSN
- 0921-5093
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β¦ Synopsis
Estimations of nucleation barriers for singledomain and multiple-domain states of a martensite phase have been obtained. A macroscopic approach, considering the free energy of a heterophase system to be a sum of the energy of the elastically stressed equilibrium phases and the energy of interfaces, was used. It has been shown that for the martensitic transformation in steels and iron alloys the nucleation of single-domain (single-crystal) martensite is impossible. The nucleation barrier for multiple-domain (twinned) martensite has been found to be of 103 times less than former estimations that had rejected any possibility of the homogeneous nucleation of martensite.
π SIMILAR VOLUMES
The martensitic transformation in the following two model systems, Fe-30 at.% Ni and In-5.25 at.% Cd, was studied by X-ray diffraction and metallography in order to answer the following question: does the nucleation of martensites occur by a soft mode mechanism or by classical heterogeneous nucleati
Martensitic nucleation near inhomogeneities is modeled using linear elasticity. The coherent strain energy due to the formation of a martensite embryo decreases when the inhomogeneity is elastically stiffer than the matrix and vice versa. A maximum reduction of 20% in strain energy is calculated for