Steel sheet with a unique coating of 55% aluminium and 45% zinc that resists
corrosion. The coating is applied in a continuous hot-dipped process, which
improves the steel's weather resistance. Galbanum® is a trademark of BHP Steel,
and the product is popular in the metal building market.
Steel coated with a thin layer of zinc to provide corrosion resistance in
underbody auto parts, garbage cans, storage tanks, or fencing wire. Sheet steel
normally must be cold-rolled prior to the galvanizing stage.
Steel is run through a molten zinc coating bath, followed by
an air stream "wipe" that controls the thickness of the zinc finish.
Zinc plating process whereby the molecules on the
positively charged zinc anode attach to the negatively charged sheet steel. The
thickness of the zinc coating is readily controlled. By increasing the electric
charge or slowing the speed of the steel through the plating area, the coating
Developing a condition on the rubbing surface of one or both mating parts
where excessive friction between high spots results in localized welding with
substantial spalling and a further roughening of the surface.
Accelerated corrosion of a metal because of an electrical contact with a
more noble metal or nonmetallic conductor in a corrosive electrolyte.
Coating steel with zinc and tin (principally
zinc) for rust proofing purposes. Formerly for the purpose of galvanizing, cut
length steel sheets were passed singly through a bath of the molten metal.
Today's galvanizing processing method consists of uncoiling and passing the
continuous length of successive coils either through a molten bath of the metal
termed Hot Dipped Galvanizing or by continuously zinc coating the uncoiled sheet
electrolytically- termed Electro-Galvanizing.
A furnace which is placed over the strip as it exits the zinc bath for the
purpose of producing a fully alloyed iron-zinc coating. The furnace can be gas
fired or induction.
The form of iron stable between 1670 (degrees) F., and 2550 (degrees) F., and
characterized by a face-centered cubic crystal structure.
An auxiliary device designed for temporarily cutting off the supply of gas
to the welding equipment except the supply to a pilot jet where fitted
The gas surrounding the inner cone of an oxy-gas flame.
A cavity generally under 1.6 mm in diameter, formed by entrapped gas during
solidification of molten metal.
A device for attachment to a gas cylinder or pipeline for reducing and
regulating the gas pressure to the working pressure required.
The thickness of sheet steel. Better-quality steel has a consistent gauge to
prevent weak spots or deformation.
GFM - Gyratory Forging Machine
The property of a surface
related to its ability to reflect light. The most common
type of gloss of interest to appearance attributes is
specular gloss. The parameters which must be specified for
the determination of this property are the angles of
incidence of the light source, the angle of viewing of the
gloss and the angular dispersions of the measuring beams.
A machine designed to hot forge a cylindrical bar shape while it is turning at
A solid polyhedral (or many sided crystal) consisting of
groups of atoms bound together in a regular geometric
pattern. In mill practice grains are usually studied only as
they appear in one plane.
(1) (Direction of) Refers to grain
fiber following the direction of rolling and parallel to
edges of strip or sheets.
(2) To bend across the grain is to
bend at right angles to the direction of rolling.
bend with the grain is to bend parallel to the direction of
rolling. In steel, the ductility in the direction of rolling
is almost twice that at right angles to the direction of
Bounding surface between crystals. When alloys yield new
phases (as in cooling), grain boundaries are the preferred
location for the appearance of the new phase. Certain
deterioration, such as season cracking and caustic
embrittlement, occur almost exclusively at grain boundaries.
A heat treatment that produces excessively large austenitic
Fiber like lines appearing on polished and etched sections
of forgings, caused by orientation of the constituents of
the metal in the direction of working during forging.
An increase in the average size of the grains in
polycrystalline metal or alloy, usually a result of heating
at elevated temperature.
Average diameter of grains in the metal under consideration,
or alternatively, the number of grains per unit area. Since
increase in grain size is paralleled by lower ductility and
impact resistance, the question of general grain size is of
great significance. The addition of certain metals affects
grain size, for example vanadium and aluminum ten to give
steel a fine grain. The ASTM has set up a grain size
standard for steels, and the McQuaid-Ehn Test has been
developed as a method of measurement.
Grain Size number
An arbitrary number calculated from the average number of individual
crystals, or grains, that appear on the etched surface of a specimen
A type of irregular surface produced when metal fractures, characterized by a
rough, grain like appearance as differentiated from a smooth silky, or fibrous,
type. It can be sub classified into trans-granular and inter-granular forms..
This type of fracture is frequently called crystalline fracture, but the
implication that the metal has crystallized is completely misleading.
The formation of grains immediately upon solidification.
The polymorph of carbon with a hexagonal crystal structure.
Gray Cast Iron
A cast iron that gives a gray fracture due to
the presence of flake graphite. Often called gray iron.
Greenfield Steel Mill
New mill that is built "from scratch," presumably on a green field.
Removing material from from a work piece with a grinding wheel or abrasive belt.
Shallow cracks formed in the surface of relatively hard materials because of
excessive grinding heat or the high sensitivity of the material.
Ground Flat Stock
Annealed and pre-ground (to close tolerances)
tool steel flats in standard sizes ready for tool room use. These are three
common grades; water hardening, oil hardening, and air hardening quality.
Device for holding the metal in the proper position, during rolling, or
Guided bend test
A bend test made by bending the specimen round a specified former.
Scratches or marks appearing parallel to edges of cold rolled strip caused by
scale or other particles which have become imbedded in or have adhered to the
rolling mill guide. Also applies to similar scratches appearing as a result of
A drill, usually with one or more flutes and with coolant passages through the
drill body, used for deep hole drilling.