Glossary Terms

STRAIN. A measure of the relative change in the size or shape of a body. Linear strain is the change per unit length of a linear dimension. True strain (or natural strain) is the natural logarithm of the ratio of the length at the moment of observation to the original gage […]

STRAIN HARDENING. An increase in hardness and strength caused by plastic deformation at temperatures below the recrystallization range.

STRESS. Force per unit area, often thought of as force acting through a small area within a plane. It can be divided into components, normal and parallel to the plane, called normal stress and shear stress, respectively. True stress denotes the stress where force and area are measured at the same […]

STRESS EQUALIZING. A low-temperature heat treatment used to balance stresses in cold-worked material without an appreciable decrease in the mechanical strength produced by cold working.

STRESS RELIEVING. Heating to a suitable temperature, holding long enough to reduce residual stresses and then cooling slowly to minimize the development of new residual stresses.

SUBCRITICAL ANNEALING. A process anneal performed on ferrous alloys at a temperature below Ac1.

SUPERCOOLING. Cooling below the temperature at which an equilibrium phase transformation can take place, without actually obtaining the transformation.