A die, commonly used in press-brake forming, that is machined horizontally with a square or rectangular crosssectional opening that provides two
edges over which metal is drawn into a channel shape.
ultimate strength
The maximum stress (tensile, compressive, or shear) a material can sustain without fracture; determined by dividing maximum load by the original
cross-sectional area of the specimen. Also known as nominal strength or maximum strength. (See Figure U1)
ultrasonic gage
“A parameter measured in a tensile test used as a measure of ductility defined by: Final Gauge Length-Original Gauge Length x 100 Original
Gauge Length” (Automotive Steel Partnership, 1991, p. 17).
undercrown
The term used to signify that the surface does not have enough height to the curvature.
undercut
See relief.
underdrive press
A press in which the driving mechanism is located within or under the press bed or below the floor line.
Figure U1:Ultimate Tensile Stress
Engineering Stress vs. Engineering Strain curve for a typical ductile sheet steel