Copper-zinc alloy

Abstract

A copper-zinc alloy includes 56-65%, by weight, of Copper (Cu), 0.2-2.0%, by weight, of Tin (Sn) for improving tensile strength of Copper (Cu) and for strengthening the corrosion resistance of Zinc (Zn), 0.1-1.0%, by weight, of Aluminum (Al) for ameliorating the yielding and tensile strength and corrosion resistance of the alloy, 0.01-0.6%, by weight, of Nickel (Ni) for improving the yielding and the tensile strength and the resistance and the heat conductivity of the alloy, lower than 0.5%, by weight, of Ferrite (Fe), with the balance being Zinc (Zn) and inevitable impurities, the alloy also includes a secondary material, which is Phosphorus (p), Arsenic (As) or both for strengthening the corrosion resistance of the alloy.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is related to the lead free Copper-Zinc alloy, which particularly focuses on decreasing the cost of lead free Copper-Zinc alloy to prevent the Copper-Zinc alloy from polluting our environment and improving mechanical ability.

2. Description of the Prior Art

Typical copper-zinc alloys comprise a number of materials, such as Iron (Fe), Aluminum (Al), Tin (Sn), Nickel (Ni), and unavoidable impurities for increasing the corrosion resistance, strengthen tensile, or the like.

For example, U.S. Pat. No. 4,990,309 to Miyafuji et al. discloses one of the typical high strength Copper-Nickel-Tin-Zinc-Aluminum alloys containing Nickel (Ni), Tin (Sn), Aluminum (Al), Manganese (Mg), Zinc (Zn), Chromium (Cr), the balance of copper and inevitable impurities.

The typical high strength Copper-Nickel-Tin-Zinc-Aluminum alloy contains a large amounts of the copper up to 80% in terms of weight. However, the copper is an expensive material that may greatly increase the cost of the alloy and that may greatly decrease or reduce the competition of the alloy.

U.S. Pat. No. 5,658,401 to Gaag et al. discloses another typical Copper-Zinc alloy for semi-finished products and articles which are highly loaded and subjected to extreme wear especially synchronizing rings.

However, the typical Copper-Zinc alloy comprises the Lead (Pb) which is toxic may damage worker health during producing Copper-Lead-Zinc alloy and will also release toxicity into drinking water which will damage human health and pollute our environment.

U.S. Pat. No. 7,128,871 to Davitz discloses a further typical silver-colored, tarnish-resistant, corrosion-resistant alloy with low percentages of copper and zinc for jewelry items, tableware items, dental items or other items that should resist tarnishing or corrosion and which require a non-brittle alloy.

However, the typical silver-colored alloy includes a large amount or percentage of the silver up to about 92-95% in terms of weight which is an expensive material that may greatly increase the cost of the alloy and that may greatly decrease or reduce the competition of the alloy.

The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional copper-zinc alloys.

SUMMARY OF THE INVENTION

The primary objective of the present invention is to provide a Copper-Zinc alloy to decrease amount of Copper material for decreasing the cost of the Copper-Zinc alloy and without any lead engaged therein for preventing the copper-zinc alloy from polluting our environment or damage human health.

In accordance with one aspect of the invention, there is provided a copper-zinc alloy comprising 56-65%, by weight, of Copper (Cu), 0.2-2.0%, by weight, of Tin (Sn) to improve the tensile strength and the corrosion resistance of Zinc (Zn), 0.1-1.0% by weight, of Aluminum (Al) to ameliorate yielding strength and the corrosion resistance of the alloy, 0.01-0.6%, by weight, of Nickel (Ni) to improve tensile strength and the corrosion resistance of Zinc (Zn) and the heat conductivity of the alloy, lower than 0.5% by weight, of Iron (Fe), and selected at least one element from Phosphorus (P) and Arsenic (As) which amounts range from 0.02-0.25% and 0.01-0.2%. Combining both materials could not be more than 0.35%, and the remaining percent, by weight, of Zinc (Zn) with inevitable impurities.

Further objectives and advantages of the present invention will become apparent from a careful reading of the detailed description provided herein below, with appropriate reference to the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A Copper-Zinc alloy in accordance with the present invention primarily comprises a Copper material (Cu), which is composed of 56 to 65 percent in terms of weight that is relatively lower than that contained in the other invention related to Lead Free Copper-Zinc alloys to decrease the cost of the Lead Free Copper-Zinc alloy, Tin (Sn), which is composed of 0.2 to 2.0 percentage in terms of weight, may ameliorate the tensile strength and also strengthen the corrosion resistance of alloy. However, when the amounts of Tin (Sn) increase, the relatively fragile or brittle material: CuZnSn will be generated and may influence the deformation of the alloy, but will improve the cutting characteristic to the alloy.

For example, when the amounts of Tin (Sn) is lower than 0.3 percentage, the cutting property of the alloy may not be improved, and when the amounts of Tin (Sn) is more than 0.8 percentage, the cutting property and the tensile strength of alloy may be improved and the characteristic of corrosion resistance may be gradually strengthened. When the amounts of Tin (Sn) is more than 2.0 percentage, the corrosion speed of zinc (Zn) is about 0.010 mm/Hr, the more Tin (Sn), the better the cutting property of the alloy and the better the corrosion resistance of zinc (Zn). However, when too much Tin (Sn) is contained in the alloy, the ductibility of the alloy will be decreased. Therefore, the best amounts of Tin (Sn) is 0.2-2.0 percentage in terms of weight.

The alloy also contains Aluminum (Al), which is 0.1-1.0 percentage, by weight, that could improve the yielding strength and the corrosion resistance of the alloy. However, it may slightly weaken the ductibility of the alloy. Too much percentage of Aluminum (Al) may decrease the stretchability of the alloy. In addition, the specific gravity of Aluminum (Al) is relatively lighter than specific gravity of the other Copper-Zinc alloy. Adding a specific amount of Aluminum (Al) may relatively decrease weight of alloy. Both Aluminum (Al) and Tin (Sn) could improve the cutting property of the alloy.

The alloy also may comprise Iron (Fe) which could be well mixed the particle of the alloy. However, Iron (Fe) which contain too much inside alloy may weaken the property of corrosion resistance. Therefore, alloy could not contain too much percentage of Iron (Fe) therein. And the amount of Iron (Fe) is preferably no more than 0.5%, in terms of weight. The alloy may further comprise unavoidable impurities therein.

The alloy which comprises Nickel (Ni) which may even particle of the alloy, strengthen yielding strength, tensile strength, corrosion resistance and heat conductivity of the alloy. Besides, the microstructure which is composed of Nickel will be more uniform after heating or extruding. The percentage of Nickel ranged preferably between 0.01 to 0.6 percentages, in terms of weight.

The remaining balance of the alloy is Zinc (Zn), which may remarkably weaken heating conductivity and electric conductivity. However, composed of Zinc could improve yielding strength. When contained amount of Zinc (Zn) is more than 20%, the corrosion may be occurred in humid environment or in sea, particularly when the environment contains Ammonia (NH₃). The cutting effect of the alloy will be improved when the percentage of Zinc (Zn) is more than 33%. Too much zinc (Zn) may decrease the malleability of the alloy. More than 45% of Zinc contained in alloy will be no economic value. In this invention, to solve corrosion problem is to increase composition of Nickel, Aluminum and Tin instead of decreasing composition of Zinc.

Further, the alloy will comprise at least one of other materials, which could be Phosphorus (P) or Arsenic (As) or both. Combining with both materials will be no more than 0.35%. The alloy which is composed of Phosphorus (P) or Arsenic (As) could strengthen the corrosion resistance. The more Phosphorus (P) and Arsenic (As) are, the better corrosion resistance of the alloy is.

Phosphorus (P) could be used as deoxidizer and mend the flowing of melting Copper (Cu) and may improve the characteristic of welding, the corrosion resistance and the anti-softness of the alloy. However adding Phosphorus (P) will weaken the heat conductivity and the electric conductivity of the alloy. In additional, an excess of Phosphorus may generate the fragile or brittle characteristic to the alloy, such that the amount of Phosphorus (P) is preferably ranged between 0.03-0.25% in terms of weight.

Arsenic (As) may be suitably melted in copper (Cu), but may greatly decrease the heat conductivity and the electric conductivity of the alloy, and Arsenic (As) may strengthen the corrosion resistance of the alloy, but will weaken the electric potential of copper (Cu). Such material which contains in alloy is preferably ranged between 0.01-0.2%, in terms of weight.

Accordingly, the Copper-Zinc alloy in accordance with the present invention includes a decreased amount of copper material for decreasing the cost of the Copper-Zinc alloy and including no lead engaged therein for preventing the copper-zinc alloy from polluting our environment.

Although this invention has been described with a certain degree of particularity, it is to be understood that the present disclosure has been made by way of example only and that numerous changes in the detailed construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as hereinafter claimed.

Claims

1. A copper-zinc alloy comprising:

56-65%, by weight, of Copper (Cu),

0.2-2.0%, by weight, of Tin (Sn),

0.1-1.0%, by weight, of Aluminum (Al),

0.01-0.6%, by weight, of Nickel (Ni),

lower than 0.5%, by weight, of Iron (Fe), and

at least one element selected from Phosphorus (P) and Arsenic (As), which are 0.03-0.25%, by weight, of Phosphorus (P), 0.01-0.2%, by weight, of Arsenic (As), combining both materials being no more than 0.35%,

with the balance being Zinc (Zn) and inevitable impurities.