Open AccessA comparison between the behaviour at the Ac 3 point of single crystal iron and polycrystal iron, both in the strained and unstrained state
Publication year - 1929
Publication title -
proceedings of the royal society of london. series a, containing papers of a mathematical and physical character
Language(s) - English
Resource type - Journals
eISSN - 2053-9150
pISSN - 0950-1207
DOI - 10.1098/rspa.1929.0140
Subject(s) - materials science , cubic crystal system , crystallography , crystal (programming language) , lattice (music) , single crystal , crystal structure , surface energy , strain (injury) , lattice constant , strain energy , composite material , thermodynamics , chemistry , diffraction , optics , physics , finite element method , medicine , programming language , computer science , acoustics
The experiments described here were undertaken with the object of investigating the effect of the initial crystal size on the behaviour of pure iron, during its passage through the Ac3 point, when the iron changes its allotropic form, and the cyrstalline structure changes from the body centred cubic lattice arrangement to the face centred cubic lattice. The energy of a crystal may be considered as consisting of the energy stored in the substance of the crystal itself and the energy stored in the surface, this surface energy being similar to the energy due to surface tension in a liquid. The energy per unit mass should be less in a specimen cut from a single crystal than in a specimen consisting of a number of crystals. Also, if a specimen is overstrained, it will contain additional energy due to the strain, and the strain will produce a greater surface energy.