T.O. 33B-1-1
Glossary 86
SPRINGBACK:
(1)
The elastic recovery of metal after stressing.
(2)
The degree to which metal tends to return to its original shape or contour after undergoing a forming
operation.
STABILIZER (RT): A device that automatically compensates for variation of main voltage and/or frequency in an
electric circuit. An example is the stabilization of filament heating current, and therefore the anode current, in an X-
ray tube.
STABILIZING TREATMENT: Any treatment intended to stabilize the structure of an alloy or the dimensions of apart.
STABLE ISOTOPE: A nuclide that does not undergo radioactive decay.
STABLE ISOTOPE (RT): A non-radioactive nuclide of a particular element.
STACKED CRYSTAL: Several crystals cemented together with the faces of the same polarity in the same direction.
STAMPING: A general term covering almost all press operation. It includes blanking, shearing, hot or cold forming,
drawing, bending, coining.
STANDARD:
(1)
A reference used as a basis for comparison or calibration.
(2)
A concept that has been established by authority, custom, or agreement to serve as a model or rule
in the measurement of quantity or the establishment of a practice or procedure.
STANDARD CUBIC CENTIMETER PER SECOND: Unit of leakage rate equivalent to one cubic centimeter at
atmospheric pressure (14.7 pounds per square inch) and standard temperature (77ºF) leaking each second.
Abbreviation is STD.cm3 /s.
STANDARD DEPTH OF PENETRATION (ET): The depth at which the eddy current field has fallen to I/ e, or 37
percent, of its strength at the surface. In practice, it is generally used to define the sensing limit of the eddy current
field.
STANDING WAVES (UT): Waves that exist in a body when the thickness of the body is equal to an integral number
of ½ wave lengths (thickness equal to ½, 1, 1 ½, 2, or 2 ½, etc., wave lengths); used with the resonance method.
STATIONARY GRID (RT): A grid in which the opaque strips are so thin and so close together that it can remain
stationary during exposure without causing images of the strips that would interfere with interpretation of the
radiograph (e.g., Lysholm grid).
STATISTICAL INSPECTION: The inspection of a proportion of the number of parts (such as 5 to 10%) as
predetermined by probability analysis. This method does not provide complete assurance of the lot quality.
STC: See DISTANCE AMPLITUDE CORRECTION.
STD. cm3/s: Abbreviation for standard cubic centimeters per second.
STEP-WEDGE CALIBRATION FILM (RT): A step-wedge comparison film, the densities of which are traceable to a
nationally recognized standardizing body. It is used for reference when determining the density or densities of a
radiograph.