FERROMAGNETIC METALS -
The attraction of repulsion of most metals when under the influence
of a magnet is very slight. A few metals, particularly iron, steel, cobalt
and nickel are strongly attracted. These metals, permeable to
magnetic flux, are called ferromagnetic. In magnetic particle testing,
we are concerned only with ferromagnetic metals.
The visual presentation of an X-ray image on a fluorescent screen.
GAMMA RAY -
The electromagnetic radiation of high-frequency and short wave-
length emitted by the nucleus of an atom during a nuclear reaction.
Gamma rays are not affected by electric fields or magnetic fields
Although produced differently then X-rays, they are identical in nature
and properties to X-rays of the same wavelength.
IONIZATION CHAMBER -
An instrument that detects and measures the electrical current
created when gas in the chamber is ionized by radiation and
becomes an electrical conductor.
LEAKAGE FIELD -
The magnetic field forced out into the air by the distortion of the field
within a part caused by the presence of a discontinuity or change in
MAGNETIC FLUX -
Magnetism may be considered a force which tends to produce a
magnetic field. Magnetic flux is a condition in this magnetic field
which accounts for the effect of the field on magnetic objects. To
picture a magnetic field in a diagram, magnetic flux is commonly
represented by flux lines that form a pattern or series of curved lines
within the magnetic field flowing through the magnet and air around
the magnet. The stronger the field, the greater the number of flux
lines. These lines are also called lines of force
MAGNETIC METALS -
Magnetic metals are those metals which are attracted be magnetism,
or which are permeable to magnetic flux.
The property of some metals, chiefly iron and steel to attract other
pieces or iron or steel is called magnetism. While most metals are
affected by magnetism to some degree, only iron and steel and some
of their alloys are sufficiently affected for the application or use of
magnetic particle inspection.
A device using radiography to ensure that the inspection technique
was appropriate. It is not intended to judge the size of discontinuities
or to establish acceptance limits for materials or products.
PENETRATION TIME -
The time allowed for the penetrant to enter surface discontinuities.