Copper and Zinc Alloy - BRASS AND MUNTZ

The most widely used Copper - zinc Alloys are Brass and Muntz Metal.

BRASSES :

This is fundamentally a binary alloy of copper with as much as 50 percent Zinc. Various Classes of Brass , depending on the proportion of Copper and Zinc, are available for various uses. Suitable types of Brass lend themselves to the following processes : Casting, Hot Forging , Cold forging , cold rolling into sheets , drawing into wire and being extruded through dies to give special shaped bars. The melting point of brass ranges from 800*C to 1000*C.

The alloy is non corrosive and air, water and some acids do not appreciably affect it. It is soft, ductile and has tensile strength with good fusibility and surface - finish characteristic. It is non - magnetic and is poor conductor of electricity. By adding small quantities of other elements the properties of brass may be greatly changed, as for example, the addition of 1 or 2 percent of lead Improves the machining quality of brass. Small amounts of tin are sometimes added to brass to increase its hardness.

Brass are used in hydraulic fittings , pump linings , in making utensils , bearings , bushes , etc.

MUNTZ METAL :

It contains 40 percent zinc and 60 per cent copper. Sometimes, a small percentage of lead is also included. It is stronger , harder , and more ductile than common brass. It is excellently suited for working at 700*C to 750*C but not for cold working.

Muntz metal is used for a wide variety of small components of machines, electrical equipment , fuses , ordnance works, and for bolts , rods, tubes, etc., It is widely employed in making such articles which are to resist wear.

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