BREMSTRAHLUNG (RT): Electromagnetic radiation emitted by charged particles when they are slowed down by
electric fields in their passage through matter. Literally, braking radiation in German.
BRIDGE CIRCUIT (ET): An electrical circuit designed to pass only the changes in voltage or current flow through a
system while eliminating the larger steady state component. Such circuits in eddy current inspection reflect the
changes in the electromagnetic variables while eliminating the larger current from the readout.
BRIGHTNESS AMPLIFIER (RT): See image intensifier.
BRINELL HARDNESS: A measure of the hardness of a metal, as determined by pressing a hard steel ball into the
smooth surface under standard conditions. For aluminum, the steel ball is 10 millimeters in diameter and total load is
500 kilograms. Results are calculated as the ratio of applied load to total surface area of indentation and are referred to
in terms of Brinell Hardness Number or BHN.
BRITTLE CRACK PROPAGATION: A very sudden propagation of a crack with the absorption of no energy except
that stored elastically in the body. Microscopic examination may reveal some deformation even though it is not
noticeable to the unaided eye.
BRITTLE FRACTURE: Fracture with little or no plastic deformation.
BRITTLENESS: The quality of a material that leads to crack propagation without appreciable plastic deformation.
BROAD-BANDED (UT): Having a relatively large bandwidth; used to describe instruments having an initial pulse
with a relatively wide bandwidth and an amplifier with response to a relatively wide range of frequencies; opposite of
narrow-banded or tuned.
BROAD BEAM (RT): An uncollimated beam containing scattered radiation as well as the primary beam.
BROAD-BEAM ABSORPTION (RT): Absorption measured under conditions in which scattered radiation is not
excluded from the measuring apparatus.
B-SCAN (UT): A data presentation method generally, applied to pulse echo techniques which yields a two dimensional
view of a cross-sectional plane through the test piece. The horizontal sweep is proportional to the test piece, with the
vertical sweep proportional to distance, showing the front and back surfaces and discontinuities between.
BUBBLER (UT): See WATER DELAY COLUMN.
BUILD-UP (RT): An increase in radiation transmitted through material because of forward scatter.
BUILD-UP FACTOR (RT): In the passage of radiation through a medium, the ratio of the total value of a specified
radiation quantity at any point to the contribution to that value from radiation reaching the point without having
undergone a collision.
BUNSEN-ROSCOE RECIPROCITY LAW (RT): States that the end result of a photochemical reaction is dependent
only on the product of the radiation intensity (1) and the duration of the exposure (t), and is independent of absolute
values of either quantity. This implies that the resultant density of a film would depend only on the products of the
radiation intensity reaching the film and the exposure time.
BURNING: Extreme overheating makes grains excessively large and causes the more fusible constituents of steel to
melt and run into the grain boundaries, or it may leave voids between the grains.
BURST: Fissures or ruptures caused by rolling or forging improperly or at improper temperatures.