Copper and brass forgings are quality parts, comparing favorably in material integrity, dimensional tolerance and surface finish with products made using other major metalworking processes. As a result of hot working, forged materials have superior density and freedom from flaws. Forming under heat and pressure in precise closed dies produces dimensional accuracy-always repeatable, part to part and lot to lot. Excellent surface finish with a clean lustrous appearance is readily available with copper and brass forgings.
This material will help design engineers and purchasing departments maximize the utility and cost advantages inherent in the specification of brass and copper forgings. It reviews competitive processes, comparing their advantages and disadvantages with forging. A a tabular guide to the tolerances commonly specified for forgings of different types is included. An extensive glossary of terms used in the industry and information required for ordering are included to improve communication between user and supplier.
Unique Combinations of Properties
Copper, brass and bronze forgings offer the designer unique combinations of properties that other metals cannot match. Alloys can be selected to utilize the following unique characteristics:
- High electrical and thermal conductivity
- Superior corrosion resistance
- High ductility
- Outstanding machinability
- Excellent joining and plating characteristics
- Superior polishing and finishing characteristics
- Non-magnetic properties
- Non-sparking characteristics
- Attractive solid colors-not just surface
Advantages of Copper and Brass Forgings
Forgings of copper and brass offer a number of outstanding advantages over parts produced by other manufacturing processes. These advantages result from the inherent properties of copper and copper alloys plus additional improvements in mechanical and physical properties imparted by the forging process.
In making a forging, the metal is worked twice under tremendous pressures-first during rod extrusion and then during forging. The double working under pressure compacts the metal and produces a very dense and refined grain or fiber structure.
The tensile strength of the parts is thereby increased, and resistance to impact and abrasion is enhanced.
The dense non-porous forged metal permits the designer to specify thinner sections without the risk of leaks due to flaws and voids. Often the thinner forged parts result in lighter weight and lower piece cost compared to other forming processes.
A forging produced in a steel die with close tolerances offers several advantages. Overall part dimensions are held closer than in sand casting. Dimensions show minimum variation from part to part and permit automatic chucking and handling in subsequent operations. The precise designs on the die surface can produce sharp impressions on the forging surface, which is not economical with other forming processes.
Low Overall Cost
Mass production of forged parts lends itself to maximum savings. However, smaller quantities of copper alloy forgings can also prove economical when specific design problems must be solved. These problems include leak integrity, close tolerances, high strength with low weight, and non-symmetrical shape.