A to Z listing
Search this site
Corrosion Glossary - U
- U-bend specimen: horseshoe-shaped test
piece used to detect the susceptibility of a material to stress corrosion cracking.
- Ultimate strength: the maximum stress
a material can sustain without fracture, determined by dividing maximum load
by the original cross-sectional area of the specimen.
- Ultrasonic: an
NDE technique which relies on
an ultrasonic beam passing through a coating and substrate and providing a signal
from the back wall which is then detected. The height of this backwall echo
depends on the discontinuity in impedance from the sprayed coating to the substrate.
Bonding flaws can be easily seen by the weakening of the back wall echo.
a step in the sequence of surface preparation involving the removal of substrate
material. Undercutting corrosion
of a scribed surface during a testing program is also an indication of poor
- Unfired pressure vessel: a vessel designed
to withstand internal pressure, neither subjected to heat from products of combustion
nor an integral part of a fired pressure vessel system.
corrosion: corrosion that proceeds at about the same rate over
a metal surface.
- Urethane: an important
resin in the
coatings industry. A true urethane
coating is a two-component product that cures when an isocyanate (the catalyst)
prompts a chemical reaction that unites the components.
- Utility: company that provides a public
service or product such as electricity, water, or telephone.
- UV stabilizers: chemicals added to
paint to absorb the ultraviolet
radiation present in sunlight.