The load-deformation plot provides information about only one specific size of specimen. The results of the tension test are more useful if they are generalized into a stress-strain diagram.

To construct a stress-strain diagram from tension test results:

(a) divide the specimen elongation data by the extensometer gage length to obtain normal strain,

(b) divide the load data by the initial specimen cross-sectional area to obtain normal stress, and

(c) plot strain on the horizontal axis and stress on the vertical axis.