Glossary | Yield Point
The Yield Point is the stress at which there is an appreciable increase in strain with no increase in stress, with the limitation that if straining continues the stress will again increase. Few materials possess a Yield Point, the most common examples are low carbon steel. If Yield Point (pt A) exists for a given material it will be indicated as the point on a stress strain curve where a zero or negative slope occurs prior to the Ultimate Tensile Strength. In the figure, point A indicates the Yield Point for 0.11%, 0.32% and 0.62% carbon steel. Notice from the figure that the heat treated and higher carbon steels do not exhibit a Yield Point.
ASTM E8 governs the determination of Yield Point for Metals.