Copper-zinc alloy for a sanitary fitting, use of a copper-zinc alloy for the manufacture of a sanitary fitting and sanitary fitting

Abstract

Copper-zinc alloy for a sanitary fitting (1) whose alloying elements have the following mass fractions: - 58.0% - 63.9% copper (Cu); - 0.3% - 0.9% aluminum (Al); - >0.1% - 0.45% tin (Sn); - 0.0% - 0.3% Iron (Fe); - 0.0% - 0.1% lead (Pb); - 0.0% - 0.1% Nickel (Ni); - 0.0% - 0.02% other alloying elements; and - Residual zinc (Zn). In addition, the use of the copper-zinc alloy for the manufacture of a sanitary fitting (1) and a sanitary fitting (1) whose fitting body (2) consists at least partially of the copper-zinc alloy is proposed.

Description

[0001] The present invention relates to a copper-zinc alloy (or brass alloy) for a sanitary fitting, the use of a copper-zinc alloy for the manufacture of a sanitary fitting, and a sanitary fitting itself. Sanitary fittings serve to provide a liquid on demand, for example, at showers, bathtubs, sinks, or washbasins.

[0002] Various requirements must be considered when manufacturing components for sanitary fittings. In particular, the material must be suitable for the production of the components. This can relate to good castability or demoldability and / or good machinability if the components need to be post-processed using machining processes.

[0003] Furthermore, it should be taken into account that the components are used for drinking water supply, for which there are different legal requirements worldwide, which are intended to ensure the continuous use of the components without contamination of the drinking water.

[0004] Another requirement is that the various components of the sanitary fitting can be recycled together as much as possible. For this purpose, it is considered advantageous for a copper-zinc alloy to have the lowest possible silicon (Si) content. This ensures that the alloy can be mixed with standard brass alloys during the manufacturing process and thus recycled.

[0005] This shows that when selecting a suitable material for sanitary fitting components, there are a variety of different objectives, some of which are in conflict with each other.

[0006] The object of the invention is therefore to at least partially solve the problems described with reference to the prior art and, in particular, to provide a copper-zinc alloy that meets the aforementioned requirements to a particularly high degree, especially with regard to its suitability for drinking water. Furthermore, the invention aims to provide a method for using a copper-zinc alloy to manufacture a sanitary fitting, wherein the copper-zinc alloy meets the aforementioned requirements to a particularly high degree, especially with regard to its suitability for drinking water. Finally, the invention aims to provide a sanitary fitting with a component that consists, at least partially, of a copper-zinc alloy that meets the aforementioned requirements to a particularly high degree, especially with regard to its suitability for drinking water.

[0007] These problems are solved with a copper-zinc alloy, an application, and a sanitary shower head according to the features of the independent claims. Further advantageous embodiments of the invention are specified in the dependent claims. It should be noted that the features listed individually in the claims can be combined with one another in any technologically meaningful way and define further embodiments of the invention. Furthermore, the features specified in the claims are further specified and explained in the description, which also presents further preferred embodiments of the invention.

[0008] This is achieved using a copper-zinc alloy for a sanitary fitting, whose alloying elements have the following mass fractions: - 58.0% - 63.9% copper (Cu); - 0.3% - 0.9% aluminum (Al); - >0.1% - 0.45% tin (Sn); - 0.0% -0.3% Iron (Fe); - 0.0% - 0.1% lead (Pb); - 0.0% - 0.1% Nickel (Ni); - 0.0% - 0.02% other alloying elements; and - Residual zinc (Zn).

[0009] Sanitary fittings primarily serve to provide water or mixed water as needed at a sink, washbasin, bathtub, or shower. The copper-zinc alloy is particularly suitable for manufacturing a component of the sanitary fitting. This component can be a water-carrying component, such as a fitting body. The fitting body can be at least partially tubular. It can be mounted on a support, such as a countertop, wall, sink, washbasin, bathtub, or shower. The fitting body can have a (protruding or branching) spout that is rigidly or movably connected to it. The spout can be at least partially tubular and / or has at least one outlet.The at least one outlet opening can, for example, be designed as a jet former or aerator, or include one.

[0010] The copper-zinc alloy is primarily a casting alloy. The mass fraction of copper (Cu) is low compared to known alloys, at 58.0% - 63.9% (for example, approximately 59.0%).

[0011] The mass fraction of aluminum (Al) can be, for example, approximately 0.7%. Aluminum increases the strength of the alpha and beta phases, particularly through solid solution hardening, without significantly affecting hot formability. Furthermore, it improves resistance to erosion corrosion as well as tarnish and weathering resistance. Aluminum also increases strength and helps achieve a high surface quality, especially in castings. In test series, aluminum showed a negative effect on dezincification resistance. The relatively low mass fraction of aluminum results in a lower proportion of the less acid-resistant beta brass. The reduced beta brass solid solution fraction is thus better distributed in an island-like, isolated manner within the dezincification-resistant alpha brass matrix.If the aluminum (Al) content is less than 0.3% by mass, there is a risk of corrosion, especially in more aggressive water conditions.

[0012] A tin (Sn) content greater than 0.1% up to 0.45% by mass (for example, approximately 0.14%) increases corrosion resistance, particularly in single-phase (alpha) copper-zinc alloys, through the formation of a protective layer and improves strength and / or sliding properties. The upper limit of 0.45% was set because no positive effects on corrosion resistance could be observed above this level.

[0013] A mass fraction of iron (Fe) of 0.0%–0.3% (for example, approximately 0.15%) can, in particular, promote grain refinement through primarily precipitated iron crystals, thereby improving the mechanical properties of the component. In test series, iron has a positive effect on dezincification resistance. This can be explained by its proven grain-refining effect. Grain refinement causes the iron content of the less acid-resistant beta brass in the brass to be finely and in isolated islands within the dezincification-resistant alpha brass matrix. The upper limit of 0.3% was set because higher iron levels can lead to the formation of hard inclusions. This is due to the relatively high melting point of iron. Hard inclusions result in surface defects that are undesirable in sanitary fittings.

[0014] The mass fraction of lead (Pb) is very low at 0.0%–0.1% (for example, approximately 0.07%). This largely or even completely prevents lead contamination of the water. In particular, increased lead release from new sanitary fittings (for example, during the first 6–12 weeks of use) can be prevented. This lead release would otherwise result from lead accumulation on the surface of the material, especially from mechanical processing, because the lead content is too low to have a significant impact on the material. The copper-zinc alloy contains a negligible mass fraction of silicon (Si) (maximum 0.02%).

[0015] The nickel content is 0.0%–0.1% by mass, preferably less than 0.05%. This increases corrosion resistance. Due to the low nickel content, no nickel is released into the water from the material. Nickel release, which can generally occur in a completely unpredictable manner, is effectively prevented, as are the effects of nickel leachate and thus potential contact reactions between humans and an exposed copper-zinc alloy.

[0016] The mass fraction of the other alloying elements in the copper-zinc alloy is 0.0% - 0.02%.

[0017] The copper-zinc alloy can, for example, contain alloying elements with the following mass fractions: - 59.0% copper (Cu); - 0.7% aluminum (Al); - 0.14% tin (Sn); - 0.15% iron (Fe); - 0.07% lead (Pb); - <0.05% Nickel (Ni); - 0.0% - 0.02% other alloying elements; and - Residual zinc (Zn).

[0018] The copper-zinc alloy may contain silicon (Si) in a mass fraction of 0.0% to 0.01% as a secondary alloying element. Higher mass fractions of silicon (Si) can increase the risk of cracking in the field and the formation of solid solutions, which can prevent or hinder machining.

[0019] The copper-zinc alloy may contain manganese (Mn) with a mass fraction of 0.0% - 0.02% as another alloying element.

[0020] The copper-zinc alloy may contain chromium (Cr) as an alloying element in a mass fraction of 0.0% - 0.005%.

[0021] The copper-zinc alloy may contain bismuth (Bi) as a secondary alloying element in a mass fraction of 0.0% to 0.005%. Higher mass fractions of bismuth (Bi) can increase the risk of cracking in the field and the formation of solid solutions, which can prevent or hinder machining.

[0022] The copper-zinc alloy may contain phosphorus (P) as a secondary alloying element with a mass fraction of 0.0% - 0.01%.

[0023] The copper-zinc alloy may contain magnesium (Mg) as an alloying element in a mass fraction of 0.0% - 0.02%.

[0024] The copper-zinc alloy may contain antimony (Sb) as a secondary alloying element with a mass fraction of 0.0% - 0.01%.

[0025] The copper-zinc alloy may contain arsenic (As) as a secondary alloying element in a mass fraction of 0.0% - 0.01%.

[0026] If the mass fraction of antimony (Sb) and / or arsenic (As) is outside the specified ranges, the increased corrosion resistance typically associated with antimony (Sb) and / or arsenic (As) only occurs in conjunction with a higher copper content, which would significantly increase the cost of the alloy. With a copper (Cu) mass fraction of 58.0%–63.9% and the addition of higher mass fractions of arsenic (As) and / or antimony (Sb), there is a risk that the arsenic (As) and / or antimony (Sb) will not be completely incorporated into the matrix, resulting in solid solution formation. Arsenic (As) and / or antimony (Sb) could then be released into the water.

[0027] The copper-zinc alloy may contain sulfur (S) as a secondary alloying element with a mass fraction of 0.0% - 0.02%.

[0028] The copper-zinc alloy may contain indium (In) as a secondary alloying element in a mass fraction of 0.0% - 0.005%.

[0029] Following a further aspect, the use of a copper-zinc alloy specified here for the manufacture of a sanitary fitting is proposed. In particular, the use of a copper-zinc alloy specified here for the manufacture of a component of the sanitary fitting, especially a water-bearing one, is proposed. This component could, in particular, be the fitting body.

[0030] The component or valve body can be cast in particular from the copper-zinc alloy.

[0031] Following a further aspect, a sanitary fitting is proposed which includes a component that consists at least partially of a copper-zinc alloy proposed here. This component is, in particular, the fitting body.

[0032] The sanitary fitting can include a mixing valve for mixing cold and hot water to produce mixed water at a desired temperature. The mixing valve can be, for example, a thermostatic mixer or a thermostatic mixing cartridge. The hot water temperature can be, in particular, a maximum of 90 °C, preferably 25 °C to 90 °C, and more preferably 55 °C to 65 °C, and / or the cold water temperature can be, in particular, a maximum of 25 °C, preferably 1 °C to 25 °C, and more preferably 5 °C to 20 °C. The mixing valve can be at least partially integrated into the fitting body.

[0033] The invention and its technical context are explained in more detail below with reference to the figure. It should be noted that the figure shows a particularly preferred embodiment of the invention, but that the invention is not limited to this embodiment. It shows, by way of example and schematically: Fig. 1: a sanitary fitting.

[0034] Fig. Figure 1 shows a sanitary fitting 1 in a perspective view. The sanitary fitting 1 comprises a component 2 in the form of a fitting body. The component 2 has a spout 3 with a discharge opening 4 through which mixed water can be discharged into an environment 5 of the sanitary fitting 1. The sanitary fitting 1 includes an actuating element 6 in the form of an actuating lever, by means of which a discharge quantity and a temperature of the mixed water can be adjusted. The component 2 consists of a copper-zinc alloy as described herein.

[0035] The sanitary fitting 1 or component 2 has a high suitability for drinking water. Reference symbol list 1 sanitary fitting 2 components 3 Outlet 4 Outlet opening 5 Environment 6 Actuating element

Claims

[1] Copper-zinc alloy for a sanitary fitting (1) the alloying elements of which have the following mass fractions: - 58.0% - 63.9% copper (Cu); - 0.3% - 0.9% aluminum (Al); - >0.1% - 0.45% tin (Sn); - 0.0% - 0.3% Iron (Fe); - 0.0% - 0.1% lead (Pb); - 0.0% - 0.1% Nickel (Ni); - 0.0% - 0.02% other alloying elements; and - Residual zinc (Zn). [2] Copper-zinc alloy according to claim 1, comprising: - 0.0% - 0.01% silicon (Si) as other alloying elements. [3] Copper-zinc alloy according to one of the preceding claims, comprising: - 0.0% - 0.02% Manganese (Mn) as other alloying elements. [4] Copper-zinc alloy according to any one of the preceding claims, comprising: - 0.0% - 0.005% Chromium (Cr) as other alloying elements. [5] Copper-zinc alloy according to any one of the preceding claims, comprising: - 0.0% - 0.005% Bismuth (Bi) as another alloying element. [6] Copper-zinc alloy according to any one of the preceding claims, comprising: - 0.0% - 0.01% Phosphorus (P) as other alloying element. [7] Copper-zinc alloy according to any one of the preceding claims, comprising: - 0.0% - 0.02% Magnesium (Mg) as other alloying elements. [8] Copper-zinc alloy according to any one of the preceding claims, comprising: - 0.0% - 0.01% Antimony (Sb) as another alloying element. [9] Copper-zinc alloy according to any one of the preceding claims, comprising: - 0.0% - 0.01% Arsenic (As) as other alloying elements. [10] Copper-zinc alloy according to any one of the preceding claims, comprising: - 0.0% - 0.02% Sulfur (S) as other alloying element. [11] Copper-zinc alloy according to any one of the preceding claims, comprising: - 0.0% - 0.005% Indium (In) as other alloying elements. [12] Use of a copper-zinc alloy according to one of the preceding claims for the manufacture of a sanitary fitting (1). [13] Sanitary fitting (1) comprising a component (2) which consists at least partially of a copper-zinc alloy according to any one of claims 1 to 11.

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