Brittle Material Stress-Strain Curve:

Figure is a stress-strain curve classical of a ductile material where the strength is small, and the plastic region is great.  A material will bear more strain (deformation) before fracture.

Below figure is a stress-strain curve classical of a brittle material while the plastic region is small and the strength of the material is high.

The tensile test supplies three descriptive facts about a material. These are the stress at which observable plastic deformation or "yielding" starts; the ultimate tensile strength or maximum intensity of load which could be carried in tension; and a percent elongation or strain (the amount the material will stretch) and the accompanying percent reduction of the cross-sectional area caused through stretching. A rupture or fracture point could also be determined.

Figure: Typical Brittle Material Stress-Strain Curve