Brass

General overview

Brass is an alloy made of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with various properties. It is a substitutional alloy: atoms of two materials may replace each other within the same crystal structure. The term is also applied to a variety of brasses and the distinction is largely historical. By alloying copper with zinc metals, brass was first obtained in England; this method was patented by James Emerson on the 13^th of July, 1781.

Properties

Brass has higher malleability than bronze or zinc. The relatively low melting point of brass and its flow characteristics make it a relatively easy material to cast. By varying the proportions of copper and zinc, the properties of brass can be changed, making brasses harder or softer. The density of brass is approximately 8300 to 8730 kilograms per cubic meter.

• Density – 8300 to 8700 kg/m³

• Specific heat - 0,377 kJ·kg⁻¹·K⁻¹

• Melting point - 880 to 940 °C

• Electrical resistivity - 0,08·10⁻⁶ Om·m

Important advantages of a brass alloy are good processability, corrosion resistance and ductility.

A significant drawback of brass is corrosion cracking.

Types of brass

There are several types of brass depending on the chemical composition. Having high ductility, brass contains not less than 30% of zinc; it is called a simple single-phase brass. If an alloy of copper and zinc contains some additional components, such as lead, then we get a special brass.

Alpha brasses are malleable; they can be worked cold, and are used in pressing, forging, or similar applications. They contain only one phase, with face-centered cubic crystal structure.

Beta brasses can only be worked hot, and are harder, stronger, and suitable for casting.

High brass has a high tensile strength and is used for springs, screws, and rivets.

Application

The wrought brass is an alloy that has good corrosion resistance, anti-friction properties and ductility. It is used in the manufacture of various accessories, interior decorations and electrical engineering.

Dual brass is used in the manufacture of small diameter tubes for the automotive and refrigeration equipment. Radiators, pipes, bushes are made from this material.

Multi brass is widely used in shipbuilding, manufacturing of bolts, door handles and fittings.

Brass jewelry is used to make decorations in homes, interiors and in the manufacture of church plates.

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