Heat treatment method of unleaded brass alloy

Abstract

A heat treatment method for unleaded brass alloy is provided to improve processability, cracking resistance, wear resistance and anti-corrosive property of unleaded brass alloy containing no lead or containing a very small amount of lead. The heat treatment method includes full annealing an unleaded brass alloy material, mechanical processing the material after full annealing and soft annealing the material after mechanical processing.

Description

FIELD OF THE INVENTION[0001]The present disclosure relates to a heat treatment method for unleaded brass alloy. More particularly, the present disclosure relates to a heat treatment method for unleaded brass alloy, intended to improve processability, cracking resistance, wear resistance and anti-corrosive property of unleaded brass alloy containing no lead or containing a very small amount of lead.BACKGROUND OF THE INVENTION[0002]In general, copper alloy is used widely in automobile parts, electronic parts, piping members (faucet metallic parts, valves, etc.), or the like, and is required to have excellent mechanical processability and anti-corrosive (anti-dezincification) property with time.[0003]It is known that addition of lead is effective for improving mechanical processability and anti-corrosive (anti-dezincification) property of copper alloy.[0004]When preparing lead-containing copper alloy, several dangerous factors always exist since such alloy contains lead that adversely ...

AI Technical Summary

Benefits of technology

[0008]The present disclosure is directed to providing a heat treatment method for unleaded brass alloy, which realizes excellent mechanical processability, anti-corrosive property and wear resistance, and improves cracking with time without adding any ingredient for improving processability, wherein the brass alloy containing no lead harmful to the human body or environment or containing such a small amount of lead that does not adversely affecting the human body or environment.

Problems solved by technology

When preparing lead-containing copper alloy, several dangerous factors always exist since such alloy contains lead that adversely affects the human body and environment.

Meanwhile, brass alloy (unleaded brass alloy) containing no lead that adversely affects the human body and environment may show poor mechanical processability.

Although such alloy provides copper alloy with improved mechanical processability (machinability) through the use of a silicon (Si) additive, it shows larger cutting resistance than lead-containing brass alloy because Si is softer than copper or lead, and tools using such alloy have low service life.

In addition, unleaded brass alloy itself has poor processability, and thus the alloy is merely applied to casting.

Therefore, the alloy as-produced may not be applied to some products, such as piping fittings, required to be processed into various shapes.

However, since bismuth is expensive and causes cracking during low-temperature processing due to its brittleness, production of articles using such bismuth-containing alloy is not cost-efficient and the resultant articles are limited in application.

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