Glossary of Copper Terms

Admiralty brass	70/30 brass with 1% tin added for extra corrosion resistance.
Ageing	Copper alloys such as copper-beryllium and copper chromium are hardened by heat treatment of solution treatment followed by quenching, then ageing at low temperatures to develop improved mechanical properties.
Alloy	A copper alloy is a partial or complete solid solution of copper with one or more alloying elements such as zinc, tin, nickel, aluminium or silicon.
Alpha brass	Brass containing up to 36% of zinc is usually the single alpha phase with good cold working properties.
Alpha-beta brass	Brass containing over 36% of zinc or with other additions usually has two phases present, alpha and beta.
Aluminium brass	High copper brass with aluminium added for improved corrosion resistance. This is often used for condenser tubes.
Aluminium bronze	Copper-aluminium alloy with up to 13% of aluminium, usually also with other additions such as iron, manganese, nickel and/or silicon.
Annealing (full)	Heating copper/copper alloys to 500-550^oC in order to produce complete softening.
Anode copper	Cast slabs of copper from the fire refining processes used as starters for electrolytic refining.
Antlerite	Copper sulphide ore.
Arsenical copper	Copper with arsenic additions used primarily for the manufacture of boiler fireboxes. Now obsolete.
Arsenical brass	Brass with improved corrosion resistance containing arsenic, and frequently aluminium.
ASM	American Society for Metals.
ASTM	American Society for Testing and Materials, responsible for standards for metals.
Azurite	Copper carbonate ore.
Backwardation	LME term used when the price for cash copper commands a premium over the price for copper in three months time. Caused by temporary shortages in spot supplies.
Beryllium copper	The highest strength of any copper alloy, achieved by heat treatment (ageing) and cold working.
Beta brass	A brass with very high zinc content may be mostly of beta structure. This is brittle and used only as a brazing filler alloy.
Blister copper	The copper produced after sulphur is removed; it is made by blowing air through the mixture; this produces gaseous sulphur dioxide which forms blister-like bubbles on the surface.
Blue vitriol	Copper sulphate.
Bordeaux mixture	Copper sulphate-lime mixture used as an adherent fungicide, especially for grapevines.
Bornite	Copper sulphide ore.
Brass	Copper-zinc alloy, also used to describe a memorial plate in a church, coinage or bearing block. Originally the term also covered copper-tin alloys now called bronzes. Also used to describe a tin-zinc spelter made for the manufacture of organ pipes.
Brass lump	Miners term for massive iron pyrites (fools’ gold).
Brinell Hardness	Standard hardness test using a specified load on a ball indenter (HB).
Bronze	Copper-tin alloy, term also loosely used for some other copper alloys.
Burgundy mixture	Solution of copper sulphate and sodium carbonate developed in 1885 for the prevention of mildew and other diseases on grapevines.
Busbars	Copper bar or section used for carrying heavy currents. Busbars are generally rigid when compared to cables.
Cadmium copper	Copper with an addition of cadmium for good strength and wear resistance without significant loss of conductivity.
Cathode copper	Pure copper, the product of electrolytic refining supplied for melting for the manufacture of products.
Cartridge brass	70/30 brass with good cold working properties.
CEN	European Standards Organisation. ‘EN’ standards are being adopted by all European countries.
Chalcocite, copper glance	Cuprous sulphide ore.
Chalcopyrite	Copper sulphide ore.
Chrysocolla	Copper silicate ore.
Cold working	Deforming a metal at a temperature below that of recrystallisation so that the metal hardens.
Continuous casting	Production method for castings where the molten metal is continuously poured into an open mould while the solidified metal is slowly withdrawn and coiled or cut to length by flying saw. May be a vertical, sidecasting or upcasting process.
Common brass	63/37 brass, standard cheap brass for cold working. It is now usually a 64/36 alloy to give improved corrosion resistance.
Contango	LME term applied when the price quoted for copper due for delivery in three months’ time is higher than that for cash copper on that day. This is the normal market situation, financing the interest charge.
Copper bottom	To sheath the bottom of ships with copper to prevent attack by the Toredo worm and prevent the attachment of biofouling including molluscs that slow the ship, first applied to British ships in 1761. Now used as a term of assurance of quality.
Copper head	A venomous snake, common in the United States of America
Copper-nickel	Covers copper alloys with less than 50% of nickel.
Copper nose	Slang term for inflamed nose, acne rosaaca, a bacterial infection treatable by antibiotics.
Copper plate	A polished plate of copper on which a design is engraved for printing.
Copper wall	Term used in sugar making to describe a double row of copper pans served by a common fire.
Covellite	Copper sulphide ore.
Cuprite	Copper oxide ore.
Cupronickel	An alternative term for copper-nickel alloy.
Deep drawing	Forming hollow components by using a punch and die to give significant plastic deformation.
Deoxidised copper	Copper that has had deoxidiser added to reduce oxygen. Phosphorus is commonly added but other elements such as boron or magnesium may be used.
Dezincification	Selective corrosion of the beta phase of duplex brass that leaves a copper residue under a ‘meringue’ of zinc oxide.
DIN	German National Standards Organisation
DGS	Director General Ships standards - obsolete, replaced by NES series, which in turn has been replaced by DSTAN (UK Defence Standardisation).
DHP	Phosphorus deoxidised copper (previously known as ‘Dona’ copper).
DLP	Deoxidised copper, low phosphorus.
DTD	Directorate of Technical Development, military specifications.
Drawing	The process of pulling a metal through a die to reduce the cross section, usually performed cold.
Ductility	Ease with which material can be formed, for example by drawing, bending or rolling. The property is usually measured as elongation in a tensile test or by a bend or deep-drawability test.
Duplex brass	See alpha-beta brass.
ETP	Electrolytic tough pitch copper, standard high conductivity copper.
Extrusion	A hot working process in which a heated billet is forced to deform by being pushed through a die to produce a long product of uniform cross-section.
Extrusion ratio	The ratio of the cross-sectional area of a billet to that of the extruded product.
Fire-refined copper	Copper refined by melting and processing in an open hearth or rotary furnace.
Galvanic compatibility	When exposed to seawater or any electrolyte, metals show a voltage dependent on the electrochemical series. Metals with near-similar voltages are compatible. Metals with differing voltages are likely to cause galvanic corrosion. It is always the anode which corrodes.
Gangue	The unwanted rock in copper ore.
German silver	Obsolete term for nickel silver.
Gilding metal	Brass with high copper, usually 90/10 but sometimes 80/20.
Gunmetal	Copper-tin-zinc casting alloy.
Heat treatable alloy	An alloy capable of being strengthened by heat treatment, usually involving solution treatment followed by ageing (precipitation) treatment.
High conductivity copper	Standard form of copper with a purity giving a conductivity of 100% IACS or more.
High tensile brass	Brass with additions, typically iron, nickel, manganese and/or aluminium to give better strength and, usually, better corrosion resistance.
Hipping	A proprietary process for treating metals at very high pressures to compact them to produce good properties.
Hot working	Plastic deformation of a metal at a temperature high enough to promote recrystallisation, thus preventing cold working.
IACS	International annealed copper standard, a value for conductivity agreed in 1913 with copper being given the value of 100%, equivalent to 58MS/m or a mass resistivity of 0.15176 Ωg/m². Advances in refining mean that high conductivity copper is now frequently of 103% conductivity.
ICA	International Copper Association.
INCRA	International Copper Research Association, now superseded by ICA.
ISO	International Standards Organisation.
Leaded brass	Usually a duplex brass with an addition of lead to give excellent machinability.
LME	London Metal Exchange.
Malachite	Copper carbonate ore.
Manganese bronze	Obsolete term for high tensile brass.
MIL	American military specifications.
Monel	A nickel-copper alloy, usually 70/30, originally produced directly from a copper-nickel ore in Sudbury, Ontario.
Muntz metal	A 60/40 brass with good castability and hot working properties.
Native copper	Pure copper that occurs in nature without being bound up within an ore.
Naval brass	60/40 brass with 1% tin added for extra corrosion resistance.
Near net shape forming	Forming a product near to final shape so that it needs little further finishing.
NES	Naval Engineering Standards.
Nickel silver	Copper-nickel-zinc alloy.
Oxygen-free copper	Copper melted and cast under controlled atmosphere to give low residual oxygen content.
Oxygen-free electronic copper	Oxygen free copper containing low residual volatile elements.
Patina	A protective film that develops on copper on exposure to the atmosphere. In most non-polluted environments it is basic copper carbonate but in industrial and urban areas it is mainly basic copper sulphate.
Paris Green	Copper-arsenic compound.
Phosphor bronze	A copper-tin phosphorous alloy, hard and strong.
Poling	Part of the old fire refining process that involves reducing the oxidised charge by submerging green wood in the liquid copper.
Red Brass	American term for copper-tin-zinc alloy (gunmetal).
Rivet brass	American term for common brass.
Rockwell Hardness	Standard American hardness test with several ranges of loads and indenters, HRB, HRC.
SAE	Society of Automotive Engineers (USA)
Tough pitch copper	Obsolete term for copper containing oxygen at about 0.03-0.07% which gave a level ‘set’ to the top of a wirebar when statically cast horizontally .
Verdigris	A strikingly green corrosion product that forms on copper in some circumstances, a complex basic copper acetate. Unlike a patina, it is water-soluble.
Vickers Hardness	Standard hardness test using a load on a diamond pyramid indenter (HV, VPN or VHN).
Wrought product	Component made by hot or cold deformation of a cast product, removing the original cast structure.
Yellow brass	American term for 67/33 brass.