(Chemical symbol Mn.) - Element No. 25 of the periodic system; atomic weight 54.93. Lustrous, reddish-white metal of hard brittle and, therefore, non-malleable character. The metal is used in large quantities in the form of Spiegel (See) and Ferromanganese (See) for steel manufacture as well as in manganese and many copper-base alloys. Its principal function is as an alloy in steel making: (1) It is ferrite-strengthening and carbide forming element. It increases hardenability inexpensively, with a tendency toward embrittlement when too high carbon and too high manganese accompany each other. (2) It counteracts brittleness from sulfur.
(Steel) - Characteristic of No.5 Temper Not a defect in No. 5 dead soft temper. Long vein-like marks appearing of the surface of certain metals, in the direction of the maximum shear stress, when the metal is subjected to deformation beyond the yield point. Also called stretcher strains, similar occurrence in certain aluminum alloys, etc. (See Stretcher Strains.)
Contain from 0.10 to 0.30% carbon and less than ?0.60% manganese. (The product of Basic Oxygen, Bessemer, Open Hearth or ?Electric Processes.)
80% cu. A copper-zinc alloy containing 20% zinc. Is a light golden color, very ductile, suitable for cupping, drawing, forming, etc. Because of its good strength and corrosion resistance it is used for flexible metal hose, metal bellows, etc.
A term applying to steel sheets that have been terne coated (Lead and Tin) by immersion in a bath of Terne Metal (See Terne Plate).
Sheet having a superior surface on one side with respect to freedom from surface imperfections and supplied with a maximum degree of flatness, for use as a plate in offset printing.
Steel with less than eutectoid percentage of carbon, (See Eutectoid Steel)
A steel having more than the eutectoid percentage of carbon. (See Eutectoid Steel)
(1) Brittleness of metal, resulting from the occlusion of hydrogen (usually as a by-product of pickling or by co-deposition in electroplating). (2) A condition of low ductility resulting from hydrogen absorption and internal pressure developed subsequently. Electrolytic copper exhibits similar results when exposed to reducing atmosphere at elevated temperature.
Plastic deformation of metal at a temperature sufficiently high not to create strain hardening. The lower limit of temperature for this process is the recrystallization temperature.
In steel mill practice, a process whereby ferrous alloy base metals are dipped into molten metal, usually zinc, tin, or tame, for the purpose of fixing a rust resistant coating.
Stress is proportional to strain in the elastic range. The value of the stress at which a material ceases to obey Hooke?s law is known as the elastic limit.
65% A copper-zinc alloy containing 35% zinc. Possesses high tensile strength. Used for springs, screws, rivets, etc.
Altering the properties of a metal by subjecting it to a sequence of temperature changes, time of retention at specific temperature and rate of cooling therefrom being as important as the temperature itself. Heat treatment usually markedly affects strength, hardness, ductility, malleability, and similar properties of both metals and their alloys.
The product of a single melting operation in a furnace, starting with the charging of raw materials and ending with the tapping of molten metal and consequently identical in its characteristics.
Degree to which a metal will resist cutting, abrasion, penetration, bending and stretching, The indicated hardness of metals will differ somewhat with the specific apparatus measuring hardness, See Brinell Hardness, Rockwell Hardness, Vickers Hardness, Scleroscope Hardness. Tensile Strength also is an indication of hardness. ?
Any process which increases the hardness of a metal, Usually heating and quenching certain iron base alloys from a temperature either within or above the critical temperature range.
A medium or high carbon quality steel strip which has been subjected to the sequence of heating, quenching and tempering.
(A) No.1 Temper. In low carbon sheet or strip steel, stiff and springy, not suitable for bending in any direction. It is the hardest temper obtainable by hard cold rolling. (B) In Stainless Steel Strip, tempers are based on minimum tensile or yield strength. For Chromium-Nickel grades Full Hard temper is 185,000 TS, 140,000 YS Min. Term also used in connection with copper base alloys and considered synonymous with Hard Temper.
Steel sheet or strip, reduced either hot or cold, cleaned, annealed, and then cold-rolled to a bright finish.
Used principally on iron and steel, means heating the metal to about 100?F. above the critical temperature range, followed by "soaking" at this point and slow cooling below the critical temperature.
A series of relatively short surface scratches variable in form and severity. Refer to Galling
Nicking and breaking a bar by means of sudden impact, to enable macroscopic study of the fractured surface.
Defects caused in metal by continued fabrication of overlapping surfaces.
Kinking or breakage due to curving of metal strip on a radius so small, with relation to thickness, as to stretch the outer surface above its elastic limit. Not to be confused with the specific product, Fluted Tubes.
Always visible to a greater or less degree when a longitudinal section has been subjected to Macro etching, indicating the direction of work or rolling.
The shear stress required to cause plastic deformation of solid metals.
A flat Cold Rolled, prepared edge section up to ?" wide, rectangular in shape. Generally produced from hot rolled rods or specially prepared round wire by one or more cold rolling operations, primarily for the purpose of obtaining the size and section desired. May also be produced by slitting cold rolled flat metal to desired width followed by edge dressing.
Supplied cold rolled and annealed. Carbon content .85. Supplied both in coil and flat length. Used to make flat latch needles which are used in the manufacture of knitted goods.
An extremely flat, very smooth, very accurate to gage, polished, hardened and tempered spring steel produced from approximately 1.15 carbon. The name is derived from its common and principle usage.
A process of hardening a ferrous alloy by heating it above the transformation range by means of a high-temperature flame, and then cooling as required.
A process of softening a metal by the application of heat from a high temperature flame.
Steel that is ready for the market without further work or treatment. Blooms, billets, slabs, sheet bars, and wire rods are termed ?semi finished."
Shaping metal into a chosen continuous form by forcing it through a die of appropriate shape.
In brass mill terminology, Extra Spring is ten numbers hard or 68.55% reduction in thickness from the previous annealing or soft stage.
In brass mill terminology, Extra Hard is six B & S numbers hard or 50.15% reduction from the previous annealing or soft stage.
The measurement of deformation during stressing in the elastic range, permitting determination of elastic properties such as proportional limit, proof stress, yield strength by the offset method and so forth. Requires the use of special testing equipment and testing procedures such as the use of an extensometer or the plotting of a stress-strain diagram.
An apparatus for indicating the deformation of metal while it is subjected to stress.
Hardened and tempered, blue polished. Carbon content about 1.00, Chromium .17. Used for the expanders in oil piston rings. Hardness 30 N 70 to 73. Range of sizes run for grooves "3/32 to ?" wide with the steel approximately .003 less than the grooves and thickness from .012 to .020.
Steel representing the eutectoid composition of the iron-carbon system, with about 0.80% to 0.83% carbon, the eutectoid temperature being about 1333?F. Such steel in the annealed condition consists exclusively of pearlite Steels with less than this quota of carbon are known as hypo-eutectoid and contain free ferrite in addition to the pearlite. When more carbon is present, the steel is known as hyper-eutectoid and contains free cementite. The presence of certain elements, such as nickel or chromium, lowers the eutectoid carbon content.
In metallography, the process of revealing structural details by the preferential attack of reagents on a metal surface.
Maximum alternating stress which a given material will withstand for an indefinite number of times without causing fatigue failure.
Raising or indenting a design in relief on a sheet or strip of metal by passing between rolls of desired pattern. (See Patterned or Embossed in this Dictionary.)
Increase in length which occurs before a metal is fractured, when subjected to stress. This is usually expressed as a percentage of the original length and is a measure of the ductility of the metal.
The trade name applied to the first aluminum-copper- magnesium type of age-hardenable alloy (17S), which contains nominally 4% Cu, ?% Mg. The term is sometimes used to include the class of wrought aluminum-copper-magnesium alloys that harden during aging at room temperature.
The property of metals that enables them to be mechanically deformed when cold, without fracture. In steel, ductility is usually measured by elongation and reduction of area as determined in a tensile test.
Finish obtained by cold rolling on polished rolls without the use of any coolant or metal lubricant, of material previously plain pickled, giving a burnished appearance.
A term given to an annealed and polished high carbon tool steel rod usually round and centerless ground. The sizes range in round stock from .013 to 1?" diameter, Commercial qualities embrace water and oil hardening grades. A less popular but nevertheless standard grade is a non-deforming quality. Drill Rods are used principally by machinists and tool and die makers for punches, drills, taps, dowel pins, screw machine parts, small tools, etc.
Reheated after hardening to a temperature below the critical for the purpose of changing the hardness of the steel. (See Tempering.)
A hardened and tempered spring steel strip, usually blued, produced from approximately .85 carbon cold rolled spring steel strip speciallly selected for straightness and good edges. Sometimes hand straightened or straightened by grinding and cut to desired lengths. This product is used in the printing trade as a blade to uniformly remove excess ink ("dope") from the rolls; hence its name.
A concave surface departing from a straight line edge to edge. Indicates transverse or across the width.
Lines of markings caused on drawn or extruded products by minor imperfections in the surface of the die.
(Chemical Symbol Zr.) - Element No. 40 of the periodic system. Atomic weight 91.22. Specific gravity 6.5 and melting point at about 3200? +/- 1300?F. Because of its great affinity for oxygen and combines readily with nitrogen and sulfur it is used as a deoxidizer and scavenger in steel making. It is used as an alloy with nickel for cutting tools and is used in copper alloys.
(Chemical Symbol Zn) - Element No. 30 of the periodic system; atomic weight 65.38. Blue-white metal; when pure, malleable and ductile even at ordinary temperatures; melting point 7870?F., boiling point 16650?F., specific gravity 7.14. Can be electrodeposited; it is extensively used as a coating for steel (See Galvanizing) and sheet zinc finds many outlets, such as dry batteries, etc. Zinc-base alloys are of great importance in die casting. Its most important alloy is brass.
The coefficient of elasticity of stretching. For a stretched wire, Young?s Modulus is the ratio of stretching force per unit cross-sectional area to the elongation per unit length. The values of Young?s Modulus for metals are of the order 1012 dynes per square cm. (See Modulus of Elasticity.)
The load per unit of original cross section at which, in soft steel, a marked increase in deformation occurs without increase in load.
Light rays, excited usually by the impact of cathode rays on matter, which have wave lengths between about 10-6 cm, and 10-9 cm; also written X-rays, same as Roentgen rays.
Iron containing only a very small amount of other elements, but containing 1-3% by weight of slag in the form of particles elongated in one direction, giving the iron a characteristic grain. Is more rust-resistant than steel and welds more easily.
The characteristic or group of characteristic that determines the ease of forming a metal into desired shapes. ?
Increase in resistance to deformation (i.e. in hardness) produced by cold working.
Spring steel wires produced from acid open-hearth steels (see notes at MB GRADE).
A process used to join metals by the application of heat. Fusion welding, which includes gas, arc, and resistance welding, Requires that the parent metals be melted. This distinguishes fusion welding from brazing. In pressure welding joining is accomplished by the use of heat and pressure without melting. The parts that are being welded are pressed together and heated simultaneously, so that recrystalization occurs across the interface.
Not flat. A slight wave following the direction of rolling and beyond the standard limitation for flatness.
Process of hardening high carbon steels by quenching in water or brine, after heating.
Usually supplied cold rolled and annealed in large widths and cut and hardened by the spring manufacturers. Carbon content about 1.15 and Tungsten .17, extra precision rolled.
Sheets that have prohibited defects, for example seams and buckled plates. Generally fit for remelting purposes only.
Standard method for measuring the hardness of metals, particularly those with extremely hard surfaces; the surface is subjected to a standard pressure for a standard length of time by means of a pyramid-shaped diamond. The diagonal of the resulting indention is measured under a microscope and the Vickers Hardness value read from a conversion table.
Hardened, tempered and white polished extra precision rolled. Carbon content about 1 .00. Steel must withstand great fatigue stresses.
(Chemical Symbol V) - Element No. 23 of the periodic system; atomic weight 50.95. Gray-white, hard metal, unaffected by atmospheric influences or alkalies but soluble in most strong acids; melting point 31190?F.; boiling point about 61500?F. specific gravity 5.87. it cannot be electrodeposited. Its principal functions as an alloy in the making of tool steels. (1) Elevates coarsening temperature of austenite (promotes fine grain). (2) Increases hardenability (when dissolved). (3) Resists tempering and causes marked secondary hardening.
Mill finish coiled or flat sheet of unspecified composition and properties produced in specific standard sizes and suitable for general building trade usage.
(1) A metal working operation similar to forging. (2) The process of axial flow under axial compression of metal, as in forming heads on rivets by flattening the end of wire.
Transverse slipping of successive layers of a coil so that the edge of the coil is conical rather than flat.
Surface discoloration on a metal, usually from a thin film of oxide or sulfide.
Arrangement of rolling mills, in direct line, allowing the metal to pass from one set of rolls into the next.
(1) Oxidation of metal due to heat, resulting in relatively heavy surface layers of oxide. (2) Removal of scale from metal.
(Scabby) - A blemish caused on a casting by eruption of gas from the mold face or by uneven mold surface; or occurring where the skin from a blowhole has partly burned away and is not welded.
An accelerated corrosion test in which the metal specimens are exposed to a fine mist of salt water solution either continuously or intermittently.
Abbreviation for Society of Automotive Engineers. This organization has specified common and alloy steels and copper vase alloys in accordance with a numerical index system allowing approximation of the composition of the metal. The last two digits always indicate the carbon content, usually within 0.05%. See AISI-SAE specifications.
(1) The removal of residual stresses by localized plastic flow as the result of low-temperature annealing operations; performed on cold worked metals without altering the grain structure or strength properties substantially.