Yield Strength
The stress at which a material begins to deform plastically. Below this point, the material can generally return to its original shape after unloading.
Engineering Interpretation
Elastic LimitPermanent deformation begins. In design practice, the selected allowable stress is normally reduced from material strength using an appropriate factor of safety and the relevant design standard.
Ultimate Tensile Strength
The maximum engineering tensile stress a material can withstand before necking and eventual fracture. UTS is a key measure of the material's overall tensile capacity.
Engineering Interpretation
Maximum Tensile CapacityMaximum tensile stress. In design practice, the selected allowable stress is normally reduced from material strength using an appropriate factor of safety and the relevant design standard.
Fracture Strength
The engineering stress recorded when the specimen finally fractures. For ductile materials, fracture occurs after the stress has passed through the UTS and the specimen has necked.
Engineering Interpretation
Rupture PointFinal rupture point. In design practice, the selected allowable stress is normally reduced from material strength using an appropriate factor of safety and the relevant design standard.