u-bend die

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.

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.