Page 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12
GLOSSARY OF TERMS
ADMIRALTY (443) — 71% copper plus zinc with 1% tin; largely used for condenser tubes.

ALLOY — a composition of two or more commercially pure metals.

ALPHA BRASS — any brass containing more than approximately 64% copper which normally shows only Alpha crystals under the microscope.

ALTERNATING STRESS — the cyclical change from tension to compression and back again in the metal. Example — reversal of spring deflections.

ALUMINUM BRASS (687) REVALONฎ — a metal containing 77% copper, 21% zinc and 2% aluminum as its chief constituents.

ALUMINUM SILICON BRONZE (642) — alloy consisting chiefly of copper with aluminum and silicon added to give it additional qualities of strength and hardness.

AMORPHOUS— refers to absence of crystalline structure.

ANNEAL — process of softening metals by subjection to moderate or high temperatures. The hardness of annealed metals will vary with the degree of anneal.

ARCHITECTURAL BRONZE (385) — actually a special brass whose composition and properties render it suitable for extrusion into complicated shapes for architectural and industrial use.

ASME — American Society of Mechanical Engineers —a nationally recognized professional group of engineers whose fundamental purpose is to exchange engineering information among its membership.

ASTM — American Society for Testing and Materials—this is the foremost body of specification writers in the world.

BERYLLIUM COPPER (170, 172, 175) — a copper-base alloy whose chief addition is beryllium. The principal properties of the alloy are great hardness, resistance to fatigue failure and an ability to be tempered.

BETA BRASS — a copper zinc phase which forms when zinc is between about 36 and 50%. Very ductile at hot working temperatures. Contrast with “alpha” phase or gamma” etc.

BRASS — any alloy of copper with zinc as the principal alloying agent, with or without small quantities of some other metals.

BRINNELL — a test used for measuring the hardness of a specimen wherein a steel ball of standard diameter is pressed into the test sample under a given load.

“B” SCALE — (Rockwell) — a specific scale of numbers used in the Rockwell testing of specimens whenever a 1/16” ball with 100 Kg load is applied.

B. & S. GAUGE — The Brown and Sharpe or American Wire Gauge — the diameters of wires having successive numbers in this gauge are in the ratio of 1. 123 to 1. also used for strip or sheet.

CARTRIDGE BRASS (260) — an alloy composed of 70% copper, 30% zinc providing combined strength ductility and resistance to corrosion. Is well — suited to deep drawing of all kinds.

CATALYSIS — acceleration of a chemical reaction by a substance (catalytic agent) which itself appears to remain unchanged.

CATHODE — the negative electrode of a cell.

COLD DRAWN — a term used to define the process of pulling a material through a set of dies designed to reduce the cross — sectional area of the metal at essentially room temperature — for tube, rod and wire.

COLD ROLLED — the reduction in gauge of metal by rolling at room temperatures — for strip, sheet and rolled bar.

COLD WORKING — a general term used to describe the variety of processes used to change the form of metals well below the softening temperature.

COMMERCIAL BRONZE (220) — an alloy containing 90% copper, 10% zinc; so called because of its bronze Color.

COMMERCIAL TOLERANCES — the “plus” and/or “minus” allowances that are acceptable on a specified dimension.

CONCENTRATION CELL— an electrolytic cell caused by concentration differences in the electrolyte.

CONDENSER TUBE (Also heat exchanger tube) — tube manufactured to special requirements as to straightness, tolerances, finish, temper and freedom from physical defects.

CORRODING MEDIUM — the chemical substance that corrodes.

CRYSTAL — a solid assembly of atoms, regularly arranged in three dimensional space.

CUPRO-NICKEL (See 700 Series.) — Several copper — nickel alloy compositions especially resistant to corrosion by salt water.

DEALUMINIFICATION — form of corrosion applying to Aluminum Bronzes of multi — phase crystal structure. (See Dezincification)

DEOXIDIZED — a term applied to any metal or alloy to indicate its having been treated to remove Oxygen. It is specially applied to copper and refers to removal of oxygen by means of phosphorus or other strong deoxidizing agents.

DEZINCIFICATION — a form of corrosion of brass characterized by solution followed by deposition of the copper back on the brass.

DISSOCIATION — breaking up of molecules into ions.

DRAWING — a process used to pull rod, tube, or wire through a set of dies for the purpose of reducing the cross — sectional area, hardening the metal, or changing its shape.

DUCTILITY — the inherent property of a metal denoting its ability to be cold or hot worked.

ELASTIC LIMIT — the unit stress to which metal can be put without permanent deformation.

ELECTROLYSIS — the decomposition of metals by means of an electric current.

ELECTROLYTIC COPPER — copper that has been refined by electrolytic deposition. Used for manufacture of tough pitch copper and copper alloys.

ELECTROLYTIC TOUGH PITCH COPPER — the remelted electrolytic copper containing about .03% oxygen comprising the bulk of copper” products.

ELECTROMOTIVE SERIES — a series in which the metals are arranged according to their normal electrode potentials.

ELONGATION — the stretch of metal under a tensile stress. The percentage of elongation is a measure of the ductility of metals.

EROSION-CORROSION — dual action taking place upon metal exposure to corrosive fluids which result in local perforation and due also to excessive velocity or turbulence.

EXTRUSION — the pushing of metal, usually at high temperature, through a die to form various shapes.

FATIGUE — the failure of metals by repeated or alternate stresses which are lower than static stresses which cause breakage.

FORGING ROD (377) — metal fabricated to rod or shape which will be later cut up, preheated and shaped while hot by the blow of a hammer or in a die.

FREE-MACHINING — ability to be cut easily by a cutting tool. Leaded brasses and tellurium copper exhibit this quality.

“F” SCALE — (Rockwell) — a specific scale of numbers adapted in the Rockwell test for measuring the surface hardness of a metal by use of a 1/16” steel ball with a 60 Kg load. (See “B” Scale.)

FULL HARD — the temper of metal cold rolled 4 B. & S. numbers or approximately 37%.

GALVANIC ACTION — a type of corrosion wherein decomposition of a metal takes place by means of an electric current that is set up whenever two dissimilar metals are in contact with each other in a conducting solution.

GAUGE — 1) a measure of the thickness of the metal,
                 2) an instrument used to measure the dimensions.

GILDING METAL (210) — a copper — zinc alloy containing 95% copper, 5% zinc. It is used chiefly on the basis of its color.

GRAIN BOUNDARIES....the boundaries between individual crystals or grains in metals.

GRAIN GROWTH — an increase in the grain size of metal.

GRAIN SIZE — the size of grains or crystals in metal, usually referred to in terms of average or mean diameter and expressed in millimeters, e.g., .010 mm is very small and .200 mm is very large.

HARDNESS — same as Temper.

HERCULOY (655) — a name applied to Revere Silicon Bronze. Its outstanding characteristics are high strength and resistance to corrosion.

HOT ROLLING — a process of fabrication used to reduce the cross — sectional area of metal at a temperature above the softening Point — usually above 1000ฐF for copper metals.

HOT WORKED — a term describing a metal that has been processed at a temperature above the softening point.

INTERNAL STRESS — the load per unit area developed inside a body by cold working or deformation.

ION — an electrically charged atom or radicle whose migration effects the transportation of electricty through electrolytes and occasionally through gases. Positively charged Ions are known as "Cations” and negatively charged Ions are known as ‘Anions”.

IONIZATION — the production of Ions from molecules such as Salts, etc.

LEADED BRASSES — a special group of copper-zinc alloys that contain small amounts of lead which imparts free-machining properties to the metal. (See alloys in 300 series.)

MERCUROUS NITRATE TEST — an accelerated corrosion test whereby the use of mercury salts determines the presence of applied or residual stresses or their combination, which might bring about the failure of the metal in service or storage through ‘season cracking”.

MIXTURE — a term used to denote an alloy or composition.

MOLECULE — a combination of two or more atoms.

MONEL METAL — a 66% nickel-copper alloy.

MUNTZ METAL (280) — a copper-zinc alloy having 60% copper content.

NAVAL BRASS (464) — a 60% copper-zinc alloy also containing 3/4% tin.

NICKEL SILVER — a name given to a group of copper-zinc nickel alloys which produce a metal of usually white color. (See 700 series.)

NONFERROUS — a term applied to metallic alloys not composed mainly of iron.

NON-OXIDIZING — a term used to describe resistance to oxidation.

OFHC* — a combination of letters meaning “Oxygen Free High Conductivity.’ *A registered trademark of American Metal Climax, Inc. for their oxygen free copper.

ORANGE PEEL — a rough surface defect obtained on cold working brass that resembles orange peel.

PHOSPHOR BRONZE — copper-tin alloys deoxidized by phosphorus — highly useful as material for springs. (See 500 series.)

PHOSPHOR DEOXIDIZED COPPER (U0 & 122) — copper that has been deoxidized with phosphorus.

PIERCING — an initial mill operation used in making seamless tubes by means of rolling a pre-heated
billet in a Mannesmann-type mill.

PRECIPITATION HARDENING — this term is often referred to as “accelerated age hardening,” and it is a process usually involving two heat treatment operations. The metal is heated to a high enough temperature to put elements into solution in more or less equilibrium. It is them quenched, trapping these elements in this state. A further heating to moderate temperatures will allow hard particles to precipitate from the solution throughout the crystalline structure. These particles interfere with the movement within the crystal and so impart hardness and strength. Beryllium Copper (170), Chrome Copper (182) and Zirconium Copper (150) are examples, as are many aluminum alloys.

PREFERRED ORIENTATION — a term describing a condition within the metal whereby the crystals are not arranged irregularly or “at random” but have a preferred or directional orientation.

READY-FINISH ANNEAL — a mill term referring to the anneal before the final cold working process.

RECRYSTALLIZATION — the transformation taking place in grain structure of cold worked metals during the process of annealing.

RED BRASS (230) — a copper-zinc alloy having an 85% copper content.

ROCKWELL — a term used to describe a hardness test reading on metal that was made by testing equipment called the” Rockwell Hardness Tester.”

ROLLING — a general term applied to various processes which work the metal by means of rolling between cylindrical or shaped rolls.

ROMAN BRONZE — a copper-zinc alloy having a small quantity of tin. (See 464A.)

S.A.E. — Society of Automotive Engineers.

SCELERSCOPE — a device used for testing hardness of metals wherein a small hammer is dropped onto the sample from a fixed height and the hardness determined by the height of the rebound of the hammer. Especially useful for checking rolls for strip or other rolling.

SEASON CRACKING — a term describing the failure taking place on metal possessing excessive internal or external stresses when in contact with a certain corroding atmosphere. This failure, which is seen as cracks, may take place after a few days, weeks or even longer.

SINGLE PHASE ALLOYS — alloys containing only one phase. e.g., cartridge brass.

SLIP-PLANES — planes in the metal of relatively easy slip or deformation.

SPECTROSCOPE — an instrument used for analyzing the spectra of rays emitted by luminous bodies, and hence the composition of an alloy or substance.

STAMPING — a process used to shape various articles by means of a die and a punch.

STATIC-STRESS — a steady force exerted in distinction to cyclic stresses.

STRAIGHTENING MACHINES — processing equipment used for taking out the bends and kinks in tube, rod and wire.

STRESS CORROSION — same as “season cracking.”

SUPERFICIAL ROCKWELL — using the 30T or 15T scales, which are lighter penetrating loads than for “B” & “F”, and are more suitable to testing of light gauge and/or annealed materials (see Rockwell).

TELLURIDE — a compound of tellurium.

TELLURIUM COPPER — copper containing a small amount of tellurium for purpose of improving machinability.

TEMPER — the condition of a metal or alloy determining its physical properties as produced by the mechanical and thermal treatments it has received.

TENSILE STRENGTH — the maximum breaking load per unit of original cross-section areas when tested in tension.

VALENCE — the number of ions that will combine with a given ion to form a molecule.

YIELD STRENGTH — as applied to nonferrous alloys, yield strength is an empirical value determined by the stress which will produce a certain amount of elongation, usually below the point of permanent deformation. (See ASTM E-8 for definitions and test methods).