Open AccessThe behaviour of metals subjected to repeated stresses
Author(s) -
H. J. Gough,
Darlene Hanson
Publication year - 1923
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.1923.0125
Subject(s) - slipping , materials science , amorphous solid , slip (aerodynamics) , cleavage (geology) , composite material , basal plane , condensed matter physics , crystallography , structural engineering , chemistry , thermodynamics , physics , fracture (geology) , engineering
The essentially crystalline structure of metals has been definitely proved by many workers. Ewing and Rosenhain showed that if a metal is permanently deformed by straining, its structure remains Crystalline, plastic yielding being due to slipping along cleavage or gliding planes within the crystals, and, in the case of some metals, to the production of “twin” crystals. They failed to discover any signs of slipping when the applied stress was less than the primitive limit of elasticity of the material. These experiments were confined to static stresses. As the result of some interesting experimental work, Beilby advanced the theory that the process of "slip” involved a transition from the soft and crystalline phase to a hard and amorphous phase in the regions immediately adjacent to the plane of slipping, the term “amorphous” being used to indicate a state in which the molecular arrangement is haphazard in order and orientation as compared with that of the crystalline phase. The mobility of the amorphous phase involved during the process of slip is extremely transitory and the slip therefore is not reversible.