Cast Copper Alloys Summary

To be clear, this is a structured break down of all the cast copper alloys available, however, there are some of these that we do not cast, such as those that contain Beryllium. For a break down on all the cast copper alloys we manufacture, please go to either Our Most Popular Alloys or Cast Copper Alloy we Produce

Introduction

Copper has some outstanding fundamental properties and attributes, which drive its importance to industry and engineering:

• Electrical conductivity - Apart from silver, copper is the next best conductor of electricity.
• Thermal conductivity - Copper heats up and cools down quickly and provides the ideal thermal management solution.
• Antimicrobial properties - Many pathogens cannot survive on copper surfaces, and as such are used in infection control on high touch surface.
• Ductility & Formability - Copper's malleability allows it to be formed and machined and retains its core strength and does not weaken after being stressed.
• Corrosion resistance & Durability - Copper endures in hostile environments, and withstands high pressures, wide temperature ranges, corrosiove conditions.
• Recyclability - without any loss in performance, and hence why 30 percent of today’s world annual copper demand is supplied by recycled copper.
• Alloyability - Copper can be alloyed with many base elements and combinations thereof to attain very speific mechanical properties.

More than 400 copper alloys exist and an alloy will be chosen for an application based on its unique combination of properties suited for the application in quesion. These attributes and properties are a combination of the following main considerations (there are more):

1. Fatigue resistance
2. Tensile & Yield strength
3. Castbility
4. Temperature & Creep resistance
5. Hardness & Wear resistance
6. Ease of fabrication - machinability / weldability
7. Magnetic susceptability
8. Ductility at low Temperature

If you are in doubt abot a particular application, it is well worth investing time in chosing the correct copper alloy, you will be surprised at the possibilities, which are are far greater than the limited set of options most foundris present.

Over the years, copper alloys have been identified by individual names and by a variety of designation systems. Many of these names and designation codes remain stubbornly in use and are often used interchangeably. Between our workshops and foundry, you will hear at least 3 standards being used in the space of just a few minutes. Take one of the most common alloys, a Copper-Tin-Lead alloy C83600, it is commonly called 85-5-5-5, but also called LG2, sometimes CC491K, often RG5, and less often referred to as 2.1096.01 or by CuSn5Zn5Pb5. Moreover it belongs to a family referred to as Red Bronze on one side of the Atlantic and as Gun Metal on the other.

As a foundry dealing with international customers, you can imagine what kind of conversations we have had. So how best should we structure our communications? We have decided to use the American Unified Numering System, UNS, simply because it is by far the most comprehensive, with 133 alloys belonging to 8 logical (mostly ... Manganese brasses are listed among the bronzes because of their high zinc content) alloy families. All the other designation systems and standards form sub-sets of the UNS.

We are more than happy for you to use whatever designation system with which you are comfortable.

Helpful Equivalance Links

If you are more familiar with:

• the EN-1982: 2008 or 2017 and need to find equivalents.
• the old BS 1400 designations and need to find equivalents.
• if you want the complete UNS listing and wish to find equivalents or near equivalent.

The UNS alloy families

The Copper Alloy Families for Cast Copper alloys are assigned UNS numbers from C80000 to C99999. The metals are arranged in a series of eight families. These families, some of which include subclassifications, include:

• (C80100-C81200) - Pure Coppers: Coppers are high-purity metal s with a minimum designated copper content of 99.3%. They are not in tentionally alloyed but may contain traces of silver or deoxidizers. The coppers are soft and ductile and are used almost exclusively for their unsurpassed electrical and thermal conductivities in products such as terminals, connectors and (water-cooled) hot metal handling equipment
• (C81400-C82800) High Copper Alloys : Next in order of decreasing copper content are alloys with a minimum designated purity of 94% Cu. The high copper alloys are used primarily for their unique combination of high strength and good conductivity. Their corrosion resistance can be better than that of copper itself. This family canbe broken down into Chromium coppers (C81400 and C81500), and the beryllium coppers which have the highest tensile strengths of all the copper alloys. They are used in heavy duty mechanical and electromechanical equipment requiring ultrahigh strength and good electrical and/or thennal conductivity.with a tensile strength
• (C83300-C87900) Brasses: Brasses are copper alloys in which zinc is the principal alloying addition. Brasses may also contain specified quantities of lead, tin, manganese and silicon. There are five subcategories of cast brasses, including two groups of copper·tin-(lead)-zinc alloys:
• C83300-C83810 Red and Leaded Red Brasses: called gun metals in parts of the world. One of the most important brasses in terms of tonnage poured is the leaded red brass, C83600 (85-5-5-5), these alloys are used in low-pressure water valves, plumbing, hardware, pipe fittings, taps and faucets
• C84200-C84800. Semi-Red and Leaded Semi-Red Brasses: C84400, C84500 and C84800 (8 1-3-7-9, 78-3-7-12 and 76-3-6- 15) form the bulk of poured tonnage globally.
• C85200-C85800, Yellow Brasses and Leaded Yellow brasses:, which are copper·zinc-(lead) alloys; Leaded yellow brasses such as C85400 (67-1-3-29), C85700 (63- 1- 1-35) and C85800 are relatively low in cost and have excellent castability, high machinabi lity and favorable finishing characteristics. Their corrosion resistance, while reasonably good, is lower than that of the red and semi-red brasses.
• C86100-C86800, Manganese Bronzes and Leaded Manganese Bronzes: also known as high strength and leaded high strength yellow brasses, are the strongest, as cast, of all the copper alloys. The "all beta" alloys C86200 and C86300 develop typical tensile strengths of 655 and 793 MPa) or 95 and 115 ksi, respectively, without heat treatment. They are also weldable but this requires post work stress relief. They are used principally for heavy duty mechanical products requiring moderately good corrosion resistance at a reasonable cost. They have been supplanted to some extent by aluminum bronzes, which offer comparable properties but have better corrosion resistance and weldability.
• C87300-C87900, Copper-Silicon alloys: which are called silicon brasses or, if they contain more silicon than zinc, silicon bronzes. These are moderate strength alloys with good corrosion resistance and used for their casting characteristics, where their solidification behavior makes alloys in this group amenable to die, pennanent mold and investment casting methods.
• (C90000-C95999) Bronzes: originally referred to alloys in which tin was the major alloying element. Under the UNS system, the term now applies to a broader class of alloys in which the principal alloying element is neither zinc nor nickel. There are five subfamilies of bronzes among the cast copper aUoys:
• C90000-C91999: Copper-Tin Alloys (Tin Bronzes):These are hard, strong alloys with good corrosion resislance, especially against seawater. As bearings, they are wear resistant and resist pounding well. Moderately machinable. Widely used for gears, worm wheels, bearings, marine fittings, piston rings, and pump components
• C92000-C92900: Copper-Tin-Lead Alloys (Leaded Tin Bronzes):Lead improves machinability in these tin bronzes but does not materially affect mechanical properties. The alloys are essentially free-cutting versions of the tin bronzes, above, and have similar properties and uses .
• C93000-C94500: Copper-Tin-Lead Alloys (High-Leaded Tin Bronzes): Lead slightly weakens all of these bearing alloys but imparts the ability to tolerate interupted lubrication. Lead also allows dirt particles to become embeded harmlessly in the bearing's / bush surface, thereby protecting the journal / shaft. This is important in off-road equipment, and earth moving machinery. Alloy C93200 is the best-known bronze bearing alloy. Widely available and somewhat less expensive than other bearing alloys, this high leaded tin bronze is also known as "Bearing Bronze." This alloy, typical of its family, is recognized for its unsurpassed wear performance against steel journals. It can be used against unhardened and not-perfectly smooth shafts. Alloy C93500, another high leaded tin bronze, combines favorable anti friction properties with good loadcarrying capacities; it also deals withto slight shaft misalignments 7 imperfections. The higher tin content of alloy C93700 (SAE 64) gives it resistance to corrosion in mild acids, mine waters and paper mill sulfite liquors.
• C94600-C94999: Copper-Tin-Nickel Alloys (Nickel-Tin Bronzes):High strength structural castings. Easy to cast, pressure tight. Corrosion and wear resistant. C94700 is heat treatable, Alloys used for bearings, worm gears, valve stems and nuts, impellers, screw conveyors, roller bearing cages, and rail· way electrification hardware .
• C95000-C95999: Copper-Aluminum-Iron and Copper-Aluminum-Iron-Nickel Alloys (Aluminium Bronzes):The aluminum bronzes are characterized by high strength and excellent corrosion resistance. Alloys containing more than 9.5% AI can be heat treated, some to tensile strengths exceeding 120 ksi (827 MPa). Uses inelude a variety of heavy duty mechanical and structural products ineluding gears, worm drives, valve guides and seats. Excellent heavy duty bearing alloys, but do not tolerate misalignment or dirty lubricants, and generally should be used against hardened steel shafts, with both shaft and bearing machined to fine surface finishes.
• (C96200-C96900): Copper Nickel Alloys or Cupronickels:, offer excellent resistance to seawater corrosion. This, combined with their high strength and good fabricability, has found them a wide variety of uses in marine equipment. They also operat well from low to elevated temperatures. Very widely used in marine applications, as pump and valve components, fittings, flanges, elc. Beryllium-containing alloys can be heat treated after wich their tensile strenghts are weill over 750MPa (110 ksi).
• (C97300-C97800): Nickel Silvers, Copper-Nickel-Tin-Lead-Zinc alloys:, these offer excellent corrosion resistance, high castability and very good machinability. They have moderate strength. Among their useful attributes is their pleasing silvery luster.
• (C98200-C98840): Copper-Lead Alloys (Leaded Coppers) These are ultrahigh lead alloys for special purpose bearings. They have relalively low strength and poor impact properties and generally require reinforcement.
• (C99000 - C99999): Special Alloys - These are alloys whose element compositions do not fall into any of the above categories and are combined into this generic designation.