Alloys with reduced tendency to form cavities for use in water-bearing components

Abstract

The invention relates to a copper-zinc alloy, in particular for use in sanitary components, consisting of: - 58.0 to 63.0 wt.% copper (Cu), - 0.4 to 1.5 wt.% tin (Sn), - 0.1 to 2.0% by weight of manganese (Mn), - 0.2 to 2.0 wt.% silicon (Si), - 0.02 to 0.1 wt% phosphorus (P), - 0 to 0.9 wt.% aluminum (Al), - 0 to 0.3 wt.% iron (Fe), - 0 to 0.005 wt% boron (B), - 0 to a maximum of 0.1 wt% lead (Pb), - 0 to a maximum of 0.2 wt% nickel (Ni), - 0 to a maximum of 0.05 wt% bismuth (Bi), - up to a maximum of 0.2 wt.% of other components, in particular accompanying elements, with a maximum of 0.05 wt.% per component or accompanying element, - Remaining zinc (Zn), where the values ​​in wt.% are based on the total weight of the alloy. Furthermore, the invention relates to a component which consists at least partially of the copper-zinc alloy, and to methods for manufacturing this component.

Description

[0001] The present invention relates to copper-zinc alloys, in particular for use in water-bearing components, and more specifically in sanitary components. The present invention further relates to a component which consists at least partially of the copper-zinc alloy according to the invention, and to methods for manufacturing this component.

[0002] Copper-zinc alloys of various compositions are advantageously used in water-bearing components, especially those carrying drinking water, for example in sanitary installations such as pipes, fittings, showers or fittings.

[0003] Furthermore, such alloys are used in power plant or machine construction, as valves, bearings or pipes, in control, measurement and regulation technology, in vehicle construction, in precision mechanics or in electrical engineering and electronics.

[0004] Application-relevant requirements for copper-zinc alloys, particularly for use in sanitary components, include good castability, especially a low tendency to form macro-shrinkage cavities and / or micro-shrinkage cavities, and / or good machinability. Shrinkage cavities are also referred to as shrinkage pores. If individual cavities / pores can be seen with the naked eye, this is called macroporosity; otherwise, it is called microporosity (see VDG leaflet P 201 from May 2002 - Association of German Foundry Professionals). Microporosity can manifest itself as a "sponge-like" morphology in the casting.

[0005] For copper alloys, the DIN standard EN 1982:2017, dated November 2017, is particularly relevant. This standard demonstrates that methods for determining chemical compositions and material properties, especially of castings, are well known to those skilled in the art.

[0006] In practice, it is common for state-of-the-art copper-zinc alloys to add significant amounts of lead (Pb), among other things to improve the machinability of the alloy.

[0007] From the perspective of pollutant exposure, including in recycling cycles, copper-zinc alloys with the lowest possible levels of potentially harmful components such as lead (Pb), bismuth (Bi) or arsenic (As), and their compounds, are desirable.

[0008] Reducing the nickel content in copper-zinc alloys can also be relevant, as nickel (Ni) can leach from water-bearing components into the water, posing a health hazard.

[0009] Document EP 2 964 798 B1 discloses an alloy for sanitary fittings which necessarily contains 63.0 to 64.5 wt.% copper (Cu), 33.8 to 36.8 wt.% zinc (Zn), 0.17 to 0.20 wt.% lead (Pb), 0.20 to 0.70 wt.% aluminum (Al), 0.04 to 0.14 wt.% arsenic (As), 0.0 to 0.30 wt.% iron (Fe), 0.0 to 0.30 wt.% tin (Sn), 0.0 to 0.10 wt.% manganese (Mn), and residual components up to a maximum of 0.02 wt.% each. However, comparatively high proportions of lead (Pb) and arsenic (As) can be detrimental from the perspective of pollutant exposure. The disclosure in EP 2 964 798 B1 focuses on the dezincification resistance of the resulting alloys.

[0010] EP 2 806 044 A2 discloses a copper-zinc alloy with improved resistance to adhesive wear. The disclosed alloys necessarily contain 28.0 to 36.0% Zn, 0.5 to 2.3% Si, 1.5 to 2.5% Mn, 0.2 to 3.0% Ni, 0.5 to 1.5% Al, 0.1 to 1.0% Fe, optionally up to a maximum of 0.1% Pb, optionally up to a maximum of 0.2% Sn, optionally up to a maximum of 0.1% P, optionally up to 0.08% S, the remainder being Cu, as well as unavoidable impurities, with iron-nickel-manganese mixed silicides embedded in the matrix. EP 2 806 044 A2 focuses on the positive mechanical properties of copper-zinc alloys.

[0011] EP 572 959A1 discloses a brass alloy containing 62.5 to 64 wt.% Cu, 0.5 to 1.5 wt.% Pb, 0.3 to 0.4 wt.% Mn, 0.5 to 0.7 wt.% Si, 0.3 to 0.7 wt.% Al, 0.05 to 0.15 wt.% Sb, 5 to 20 ppm B, 0 to 0.25 wt.% Fe, 0 to 0.5 wt.% Ni, 0 to 0.25 wt.% Sn, and the balance Zn. The composition of the brass alloy is disadvantageous from the perspective of pollutant contamination, particularly due to comparatively high levels of lead (Pb) and arsenic (As). The focus of the disclosure in EP 572 959 A1 is on improved dezincification resistance.

[0012] Furthermore, DE 10 2013 004 081 A1 discloses a sanitary fitting body, particularly for drinking water applications, consisting of brass containing 62.5 to 64.5 wt.% Cu, up to a maximum of 36.4 wt.% Zn, up to a maximum of 0.5 wt.% Pb, 0.09 to 0.14 wt.% As, 0.3 to 0.7 wt.% Al, up to a maximum of 0.3 wt.% Fe, up to a maximum of 0.1 wt.% Mn, up to a maximum of 0.2 wt.% Ni, up to a maximum of 0.3 wt.% Sn, up to a maximum of 0.02 wt.% Si, and up to a maximum of 0.02 wt.% Sb. The disclosure in DE 10 2013 004 081 A1 is also aimed at improving dezincification resistance.

[0013] One object of the present invention is to provide an alloy which reduces or eliminates at least one of the aforementioned disadvantages or further disadvantages known from the prior art, in particular reducing or eliminating two or more of the aforementioned disadvantages.

[0014] In particular, it is a task to provide such an alloy that can be advantageously used in water-bearing components, especially in sanitary components.

[0015] At least one of the aforementioned tasks is solved by the doctrine of independent claims. Advantageous embodiments are claimed in dependent claims.

[0016] According to a first aspect of the invention, at least one of the above-mentioned problems is solved by a copper-zinc alloy, particularly for use in sanitary components, consisting of: - 58.0 to 63.0 wt.% copper (Cu), - 0.4 to 1.5 wt.% tin (Sn), - 0.1 to 2.0% by weight of manganese (Mn), - 0.2 to 2.0 wt.% silicon (Si), - 0.02 to 0.1 wt% phosphorus (P), - 0 to 0.9 wt.% aluminum (Al), - 0 to 0.3 wt.% iron (Fe), - 0 to 0.005 wt% boron (B), - 0 to a maximum of 0.1 wt% lead (Pb), - 0 to a maximum of 0.2 wt% nickel (Ni), - 0 to a maximum of 0.05 wt% bismuth (Bi), - up to a maximum of 0.2 wt.% of other components, in particular accompanying elements, with a maximum of 0.05 wt.% per component or accompanying element, - Remainder zinc (Zn), where all values ​​are in wt.%, based on the total weight of the alloy.

[0017] According to a second aspect of the invention, at least one of the above-mentioned problems is solved by a component, in particular a sanitary component, which consists at least partially of an alloy according to the first aspect of the invention and / or can be manufactured according to a method according to a third and / or fourth aspect of the invention mentioned below, in one embodiment.

[0018] According to one or the third aspect of the invention, at least one of the above-mentioned problems is solved by a method for manufacturing a component according to the second aspect of the invention, wherein at least a part of the component is manufactured using or under, in particular at least partially by, primary forming with a copper-zinc alloy according to the first aspect of the invention, or wherein manufacturing at least a part of the component comprises primary forming (of this part) with, in particular from, a copper-zinc alloy according to the first aspect of the invention.

[0019] According to one or the fourth aspect of the invention, at least one of the above-mentioned problems is solved by a method for manufacturing a component according to the second aspect of the invention, wherein at least a part of the component is manufactured by means of, or by, in particular at least partially by, forming a semi-finished product which consists at least partially of a copper-zinc alloy according to the first aspect of the invention, or wherein manufacturing at least a part of the component comprises forming a semi-finished product with, in particular made of, a copper-zinc alloy according to the first aspect of the invention.

[0020] For the purposes of this document, an alloy is understood to be a macroscopically homogeneous metallic material consisting of at least two elements, at least one of which is a metal, and the at least two elements can have any mass fractions.

[0021] In this context, a "copper-zinc alloy" is understood to be an alloy containing at least the elements copper (Cu) and zinc (Zn), wherein the alloy contains copper (Cu) by mass in the largest proportion and zinc (Zn) by mass in the second largest proportion.

[0022] For the purposes of the present invention, the “other components” may in particular include impurities (e.g. from recycling cycles) and / or intentionally added elements and / or intentionally added compounds, and in particular consist of one or more impurities and / or intentionally added elements and / or intentionally added compounds.

[0023] In preferred embodiments, the "other constituents," i.e., constituents other than copper (Cu), tin (Sn), manganese (Mn), silicon (Si), phosphorus (P), aluminum (Al), iron (Fe), boron (B), lead (Pb), nickel (Ni), bismuth (Bi), and zinc (Zn) contained in the alloy, are not added to the alloy intentionally, i.e., as part of the formulation or production of the alloy. These "other constituents" are intended to be present in the alloy as claimed, preferably in particularly small quantities (or in immeasurable quantities).

[0024] “Impurities” within the meaning of the present invention can, in particular, be undesirable but unavoidable components of the intentionally added components of the alloy, and / or can originate from recycling processes insofar as recycled material is used. For the purposes of the present invention, lead (Pb), nickel (Ni), and bismuth (Bi) are considered “impurities.”

[0025] The quantity "weight percent" (wt%) indicates the mass fraction of a component of the alloy, i.e., the relative proportion of the mass of a component to the total mass of the alloy. The composition of the copper-zinc alloy with the specified ranges must therefore be selected such that the sum of the alloy components equals 100 wt%, at least within the measurement tolerances customary for copper-zinc alloys, particularly for determining the composition of the copper-zinc alloy according to DIN 15079:2015 (July 2015 edition) using optical emission spectrometry with spark excitation. Another quantity familiar to those skilled in the art, besides "weight percent" (wt%), is "parts per million" (ppm). 1 ppm corresponds to 0.0001 wt%.

[0026] For the purposes of the invention, an alloy is considered lead-free if its lead content does not exceed 0.1 wt.%.

[0027] For the purposes of the invention, an alloy is considered bismuth-free if its bismuth content does not exceed 0.05 wt.%.

[0028] In this context, "castability" refers to the property of a material, in particular an alloy, to be processable by casting.

[0029] In this context, "casting" refers to the filling of a material, in particular a metal or alloy, in a liquid state (from the melt) into a mold and the subsequent solidification.

[0030] In this context, "cavity tendency" refers to the property of a material, in particular a metal or alloy, to form cavities when solidifying from the melt due to shrinkage of the material's volume during cooling and solidification of the melt.

[0031] In this context, "macrosh shrinkage tendency" refers to the property of a material, particularly a metal or alloy, to form shrinkage cavities during solidification of the molten metal, which are individually visible to the naked eye. Specifically, "macrosh shrinkage cavities" are defined as cavities with a minimum size of 0.5 mm.

[0032] The term "microshrinkage tendency" refers to the property of a material, particularly a metal or alloy, to form cavities during solidification from the melt, the shape and size of which are not individually discernible or distinguishable to the naked eye. Specifically, "microshrinkage cavities" are defined as cavities with a maximum dimension of 0.5 mm, which may manifest as a spongy, loose, porous fracture structure.

[0033] In this context, "microporosity" refers to the presence of micro-voids in a material, particularly in a metal or alloy.

[0034] In this context, "machinability" refers to the property of a material, in particular a metal or an alloy, to be able to be machined by cutting, in such a way that the desired components can be obtained for the respective intended application.

[0035] In this context, "machining" refers to a manufacturing process that gives a material, in particular a metal or alloy, a specific geometric shape by mechanically removing excess material in the form of chips.

[0036] In this context, "grain refinement" refers to the targeted production of a finer, smaller grain in the structure of a material, in particular a metal or an alloy.

[0037] In this context, "galvanic coating" refers to the creation of a metallic coating on a substrate, i.e., a material to be coated, by electrochemical deposition in an electrolytic bath.

[0038] In this context, "PVD coating" refers to a coating produced using a "Physical Vapor Deposition" (PVD) process. "PVD" specifically encompasses vacuum-based coating processes or thin-film technologies in which the coating material is transferred into the gas phase and the gaseous coating material is then directed to the substrate to be coated, where it condenses and forms the PVD coating.

[0039] The copper-zinc alloys described here have a comparatively high content of manganese (Mn), tin (Sn) and silicon (Si) compared to state-of-the-art alloys.

[0040] The comparatively high manganese content has the advantage that manganese phosphides are formed with the phosphorus, which is also necessarily present in the alloys according to the invention (also in comparatively high proportions), which advantageously contribute to the grain refinement of the alloy (see also the more detailed information below on phosphide formation).

[0041] Furthermore, the copper-zinc alloys according to the invention have a negligible content of potentially harmful elements such as lead (Pb) and bismuth (Bi).

[0042] The copper-zinc alloys according to the invention can therefore be described as lead-free and bismuth-free. Avoiding or minimizing bismuth (Bi) is particularly relevant for components intended for recycling.

[0043] It should also be emphasized that the copper-zinc alloys according to the invention have a comparatively low nickel (Ni) content.

[0044] Surprisingly, it has been found that copper-zinc alloys based on the above-mentioned compositions exhibit particularly good castability, especially low macro-cavity and micro-cavity tendency, but also good machinability.

[0045] Particularly due to its low microporosity, it has been shown that components consisting at least partially of the copper-zinc alloy according to the invention exhibit good sealing properties. This makes the alloy according to the invention particularly suitable for use in fluid-carrying components, especially for use in fluid-carrying components under elevated pressure.

[0046] Due to the excellent castability of the copper-zinc alloy, it is particularly well-suited for die casting with a lost core. The use of the aforementioned alloying elements results in a sufficiently fine microstructure even in the as-cast state, without the need for subsequent heat treatment.

[0047] The addition of phosphorus (P), even in small quantities, significantly refines the microstructure of the copper-zinc alloy. This results in improved feeding properties of the copper-zinc alloy, which in turn contributes to the reduction of any microporosity that may occur.

[0048] Furthermore, the presence of phosphorus (P) in the copper-zinc alloys according to the invention has a positive effect on their machinability. The addition of phosphorus (P) can lead to the formation of phosphides in combination with other alloying elements.

[0049] The presence of phosphides is associated with, among other things, the advantages described below.

[0050] According to the invention, the addition of phosphorus (P) is limited to 0.1 wt.%, in one embodiment to 0.14 wt.%, and in a further embodiment to 0.10 wt.%, since it has been found that higher phosphorus contents can lead to an increased tendency for stress cracking in the castings. Without being bound to any specific theory, it is assumed that excessively high phosphorus (P) contents can also lead to a coarsening of the phosphides.

[0051] As mentioned above, the presence of comparatively high proportions of manganese (Mn) enhances and stabilizes the grain-refining effect of phosphorus (P).

[0052] Without wishing to be bound to any theory, it is assumed that the addition of manganese (Mn) in comparatively high concentrations to achieve the desired grain refinement requires a lower concentration of phosphorus (P), which in turn reduces or contributes to the reduction of the stress cracking tendency of the copper-zinc alloy that occurs in the presence of potentially higher phosphorus concentrations.

[0053] The presence of manganese (Mn) in combination with phosphorus (P) can enable the formation of manganese phosphides. These manganese phosphides can exhibit a grain-refining effect, which in turn has a positive impact on the castability, particularly on the formation of microporous cavities, and on the machinability of the copper-zinc alloy. Accordingly, the alloys according to the invention are characterized, among other things, by the fact that a "sponge-like" morphology with significant microporosity is avoided or minimized.

[0054] The manganese content is limited to 2.0 wt.%, as higher manganese (Mn) contents can lead to coarsening of the manganese phosphides. Furthermore, excessively high manganese (Mn) contents can result in undesirably high alloy hardness. Conversely, manganese contents below 0.1 wt.% do not produce sufficient effects with regard to castability, particularly grain refinement and the associated reduction in microporosity, and machinability.

[0055] The addition of tin (Sn) to copper-zinc alloys significantly reduces the tendency for macroporosity. Tin (Sn) contents below 0.4 wt% are insufficient to achieve the desired reduction. Conversely, contents above 1.5 wt% can lead to pronounced microporosity, with correspondingly negative effects on the copper-zinc alloys.

[0056] It was found that silicon (Si) in the copper-zinc alloy has a grain-refining effect, resulting in reduced microporosity and thus improved sealing of the castings, which is particularly advantageous for water-bearing sanitary components, especially those under increased pressure. Furthermore, silicon (Si) in the copper-zinc alloy has a positive effect on its machinability.

[0057] The other components, in particular accompanying elements, do not adversely affect the positive properties of the copper-zinc alloy described here, at least not within the scope of conventional measurement methods. If the limits according to the invention are observed, this enables the production of the copper-zinc alloys from recycled material, preferably from closed-loop systems.

[0058] In one version, the copper-zinc alloy contains the following alloying elements in the following proportions: - (a) 0.4 to 1.0 wt.% tin (Sn) and / or - (b) 0.1 to 1.0 wt% manganese (Mn) and / or - (c) 0.02 to 0.14 wt% phosphorus (P) and / or - (d) 0.1 to 0.8 wt.% aluminium (Al), wherein the copper-zinc alloy preferably has all elements (a) - (c) in the ranges mentioned, or all elements (a) - (d) in the ranges mentioned.

[0059] Surprisingly, it has been found that the formulation of the copper-zinc alloys described here, with a tin content of 0.4 to 1.0 wt.% and / or a manganese content of 0.1 to 1.0 wt.% and / or a phosphorus content of 0.02 to 0.14 wt.%, exhibits positive and further improved properties, particularly good castability. Specifically, it has been shown that even a reduced tin content results in a sufficient reduction in the tendency for macroporosity, and that a reduced manganese content and / or a reduced phosphorus content results in a sufficient reduction in microporosity.

[0060] The addition of aluminium (Al) in the above-mentioned quantity range has a positive effect on the castability of the copper-zinc alloy.

[0061] The reduced levels of manganese (Mn) and phosphorus (P) make it particularly easy to control the potential formation of manganese phosphide.

[0062] Furthermore, a reduced phosphorus content can result in an even lower susceptibility to stress cracking in the castings. Likewise, a reduced phosphorus content can further prevent the coarsening of phosphides.

[0063] A reduced manganese content can further prevent the coarsening of manganese phosphides. Furthermore, it can prevent an undesirably high hardness of the alloy.

[0064] Lower levels of more expensive alloying elements also allow for more cost-effective production of the copper-zinc alloy.

[0065] In one version, the copper-zinc alloy contains the following alloying elements in the following proportions: - (a) 0.4 to 0.8 wt% tin (Sn) and / or - (b) 0.2 to 0.8 wt% manganese (Mn) and / or - (c) 0.2 to 1.2 wt.% silicon (Si) and / or - (d) 0.02 to 0.08 wt% phosphorus (P) and / or - (e) 0.3 to 0.8 wt.% aluminium (Al), wherein the copper-zinc alloy preferably comprises all elements (a) - (d) in the ranges mentioned, or all elements (a) - (e) in the ranges mentioned.

[0066] Surprisingly, it was found that a copper-zinc alloy as described herein with a tin content of 0.4 to 0.8 wt.% and / or a manganese content of 0.2 to 0.8 wt.% and / or a silicon content of 0.2 to 1.2 wt.% and / or a phosphorus content of 0.02 to 0.08 wt.% results in further advantageous properties, in particular good castability. Specifically, it was shown that even a further reduction in tin content sufficiently reduces the tendency for macroporosity, and that a further reduction in manganese content and / or phosphorus content sufficiently reduces microporosity.Without wishing to be bound to any theory, it is assumed that the presence of tin (Sn) in the claimed amounts is advantageous in reducing the tendency to form macro-shrinkage cavities, while at the same time the joint presence of manganese (Mn) and phosphorus (P) in the claimed amounts counteracts micro-shrinkage / microporosity induced by volume contraction, in particular shrinkage, shrinkage or the like.

[0067] The addition of aluminium (Al) in the above-mentioned quantity range has a positive effect on the castability of the copper-zinc alloy.

[0068] The further reduced levels of manganese (Mn) and phosphorus (P) allow for even better control of the potential formation of manganese phosphide.

[0069] An even lower phosphorus content can result in an even lower susceptibility to stress cracking in the castings. Likewise, an even lower phosphorus content can further inhibit the coarsening of the phosphides.

[0070] A lower manganese content can further inhibit the coarsening of the manganese phosphides. Furthermore, an undesirably high hardness of the alloy can be avoided even more effectively.

[0071] Even lower levels of alloying elements, which are "more expensive" depending on the market situation, e.g. manganese, generally allow for even more cost-effective production of the copper-zinc alloy.

[0072] In one embodiment, the copper-zinc alloy has a minimum iron (Fe) content of at least 0.03 wt.% and / or a (lower) maximum iron (Fe) content of at most 0.2 wt.%. Alternatively, or advantageously in combination with this minimum or (lower) maximum iron (Fe) content, or in a further embodiment in combination with this minimum and (lower) maximum iron (Fe) content, the copper-zinc alloy has a minimum boron (B) content of at least 0.001 wt.% and / or a (lower) maximum boron (B) content of at most 0.002 wt.%. The following combinations of iron (Fe) and boron (B) can be particularly advantageous: - the copper-zinc alloy contains 0 to 0.2 wt.% iron (Fe) and / or in combination with 0 to 0.002 wt.% boron (B); or - the copper-zinc alloy contains 0 to 0.3 wt.% iron (Fe) and / or in combination with 0.001 to 0.005 wt.% boron (B); or - the copper-zinc alloy contains 0.05 to 0.2 wt.% iron (Fe) and / or in combination with 0 to 0.001 wt.% boron (B); or - the copper-zinc alloy contains 0 to 0.05 wt.% iron (Fe) and / or in combination with 0.001 to 0.002 wt.% boron (B).

[0073] The addition of iron (Fe) and especially boron (B) can contribute to a grain-refining effect in the copper-zinc alloy, resulting in a positive effect on the castability and machinability of the copper-zinc alloy.

[0074] Iron (Fe) in combination with phosphorus (P) can additionally enable the formation of iron phosphides. These iron phosphides can have a grain-refining effect, which in turn has a positive impact on the castability and machinability of the copper-zinc alloy.

[0075] In certain embodiments, the iron content is limited to 0.3 wt.% and the boron content to 0.005 wt.%. Without being bound to any specific theory, it is assumed that higher contents could lead to excessive formation of intermetallic phases, resulting in a detrimental effect on the machinability of the copper-zinc alloy and the potential formation of a decorative surface.

[0076] Further reduced maximum iron (Fe) levels of max. 0.2 wt.% and further reduced maximum boron (B) levels of max. 0.002 wt.% have proven particularly beneficial for the production of decorative surfaces.

[0077] Preferably, the iron (Fe) and boron (B) contents of the copper-zinc alloy are coordinated such that a lower iron (Fe) content results in a higher boron (B) content and a lower boron (B) content results in a higher iron (Fe) content, so that an advantageous grain refinement of the copper-zinc alloy can always be ensured.

[0078] In one embodiment, the component consists of at least 25 wt.% and / or at least 25 vol.%, in particular at least 50 wt.% and / or at least 50 vol.%, in a further development at least 75 wt.% and / or at least 75 vol.%, in particular completely of an alloy according to the first aspect of the invention.

[0079] For the purposes of the present invention, “consists entirely” means that components other than impurities or additives not specifically added may be present in quantities that do not adversely affect the functionality and properties of the alloy.

[0080] The very good castability, good machinability and low tendency to form cavities of the copper-zinc alloys described here facilitates the production or machining of a component that consists at least partially of the copper-zinc alloy described here.

[0081] In one embodiment, the component has one or more passages that carry fluid, in one embodiment liquid, or are provided for this purpose, in particular equipped, or used for this purpose.

[0082] In a further development, the component has one or more passages that carry water, in one version drinking water, or are intended for this purpose, in particular equipped, or used for this purpose.

[0083] Due in part to the very low levels of harmful elements such as lead (Pb), bismuth (Bi) and nickel (Ni), the copper-zinc alloy described here is particularly suitable for use in components that carry water or are in contact with water, as there is no or only a negligible release of potentially harmful elements, ions or compounds from the copper-zinc alloy into the water.

[0084] In a preferred embodiment, the component is a sanitary component, in particular for conveying water in buildings, or a plant component, in particular for conveying liquids and / or gases in industrial plants; in a further development, it is a fitting, in particular a sanitary or plant engineering fitting.

[0085] In one embodiment, the component has at least one actuating element installed or used to change, in one embodiment to reduce, in a further development to block, in particular to shut off, a flow through, in particular a fluid flow through, which has at least one passage.

[0086] In one embodiment, the component has at least one actuating element provided or used for changing, in one embodiment reducing, in a further development blocking, in particular shutting off, a flow through, in particular a fluid flow, of at least two of the several passages and / or at least one actuating element provided or used for changing, in one embodiment reducing, in a further development blocking, in particular shutting off, a flow through, in particular a fluid flow, of at least one of the several passages and at least one further actuating element provided or used for changing, in one embodiment reducing, in a further development blocking, in particular shutting off, a flow through, in particular a fluid flow, of at least one other of the several passages.

[0087] In one embodiment, the component has at least a single- or multi-layer coating; in a further development, it has a single- or multi-layer inner coating and / or a single- or multi-layer outer coating.

[0088] A coating can improve both the mechanical and chemical properties of the component and serves in particular to protect and / or increase the value of the component.

[0089] In one version, the coating can be a galvanic coating, while in a further development, it can be a more complex coating. Galvanic coatings have the advantages, among others, of allowing coating within a wide range of parameters relevant to coatings (e.g., layer thickness or coating density), being cost-effective to produce, offering good corrosion protection, and enhancing the component's appearance.

[0090] Alternatively or additionally, the coating can (also) feature a PVD coating, as part of further training. PVD coatings offer the advantages of excellent mechanical properties, such as good impact and scratch resistance, easy cleaning, high color brilliance, and numerous design and material combination possibilities.

[0091] In one version of the component, the coating is at least partially metallic and / or includes a polymer component.

[0092] Metallic coatings serve, among other things, to improve corrosion resistance.

[0093] A coating containing plastic enables, among other things, the provision of a permanently sterile surface and improved resistance to mechanical stress. In further development, a coating containing plastic or a polymer component can be a lacquer layer, particularly for decorative purposes.

[0094] In one embodiment, a component described herein can be manufactured, in particular produced, using a method described herein.

[0095] The possibility of manufacturing at least part of a component described herein by primary forming with a copper-zinc alloy described herein, or by forming a semi-finished product made of a copper-zinc alloy described herein, means in particular that the component, which consists at least partially of a copper-zinc alloy described herein, can (preferably also) be manufactured using conventional methods for copper-zinc alloys known from the prior art. Therefore, in particular, no or only very minor modifications to existing processes and tools for copper-zinc alloys known from the prior art are necessary for the manufacture of components made of a copper-zinc alloy described herein.

[0096] In one embodiment of the process, the component, preferably after primary forming or shaping, is machined by one or more material separation processes, in a further development by machining processes, in one embodiment with a geometrically defined cutting edge, in a further development comprising sawing, planing, milling, drilling, cutting and / or thread cutting, and / or with a geometrically undefined cutting edge, in one embodiment comprising grinding, polishing, honing, lapping, blasting and / or brushing, and / or coated one or more times.

[0097] By machining the component to separate the material, it can be further processed in a variety of ways and with high accuracy, and if necessary finished or shaped, which improves the manufacturing of a complex component.

[0098] Coating the component can improve its mechanical and chemical properties. Furthermore, it can enhance the component's aesthetic appearance. Examples of implementation

[0099] The following are six exemplary embodiments of specific copper-zinc alloys to illustrate the copper-zinc alloys according to the invention (all values ​​in wt.%): Cu Sn Mn Si P Al Fe B Zn Example 1 60 0,6 0,4 0,6 0,04 0,6 0,1 0,0012 rest Example 2 60 1 0,6 0,2 0,07 0,6 0,07 0,0009 rest Example 3 60 1 1 1,4 0,07 0,6 0,07 0,0009 rest Example 4 60 1 1 1,4 0,1 0,6 0,07 0,0009 rest Example 5 60 0,6 0,4 0,6 0,04 0,05 0,1 0,0012 rest Example 6 62 0,6 0,4 0,6 0,04 0,6 0,1 0,0015 rest

[0100] The exemplary embodiments of specific copper-zinc alloys may also contain 0 to a maximum of 0.1 wt.% lead (Pb), 0 to a maximum of 0.2 wt.% nickel (Ni), 0 to a maximum of 0.05 wt.% bismuth (Bi), and a total of up to a maximum of 0.2 wt.% other components, in particular accompanying elements or impurities in the form of compounds, wherein each component or accompanying element contains a maximum of 0.05 wt.%.

[0101] Exemplary embodiment 1 is characterized by a relatively low phosphorus content of only 0.04 wt.%. The manganese content is also comparatively low at 0.4 wt.%. This ensures a particularly low susceptibility to stress cracking. Furthermore, the manganese phosphides are significantly finer than those found in alloys with higher phosphorus and manganese contents. The reduced grain-refining effect due to the lower phosphorus content and the lower proportion of manganese phosphides is compensated for by a higher boron (B) content, which is also present in the alloy as a grain refiner.

[0102] In contrast to embodiment 1, embodiment 2 has a higher phosphorus and manganese content. To control the phase fraction of phosphides, i.e., manganese phosphides and iron phosphides, embodiment 2 contains a lower amount of iron (Fe). Due to the still higher phase fraction of phosphides compared to embodiment 1 and the associated greater grain refinement, a small amount of boron (B) of only 0.0009 wt.% is included.

[0103] Exemplary embodiment 3 differs from exemplary embodiments 1 and 2 primarily in that it has a significantly higher silicon content of 1.4 wt.%. The manganese content is also somewhat higher at 1 wt.% than in exemplary embodiments 1 and 2. Overall, this alloy exhibits greater grain refinement, which in turn results in improved castability, particularly reduced microporosity, and improved machinability.

[0104] In embodiment 4, the phosphorus content is even further increased compared to embodiment 3. Embodiment 4 exhibits good grain refinement and a related improvement in castability, in particular reduced microporosity, and improved machinability, without showing an increased tendency for stress cracking or a coarsening of the phosphides.

[0105] Exemplary embodiment 5 differs from exemplary embodiments 1 to 4 in that it contains only a greatly reduced content of aluminium (Al) of only 0.05 wt.%, without having to noticeably lose positive properties, in particular very good castability, good machinability and low tendency to form macro-shrinkage cavities.

[0106] Exemplary embodiment 6 differs from exemplary embodiment 1 in that it has a higher copper content of 62 wt.%. Similar to exemplary embodiment 1, the comparatively low phosphorus content of only 0.04 wt.% and the comparatively low manganese content of only 0.4 wt.% ensure a particularly low susceptibility to stress cracking. Likewise, the manganese phosphides are significantly finer than with higher phosphorus and manganese contents. The reduced grain-refining effect due to the lower phosphorus content and the lower phase fractions of manganese phosphides is compensated for by an even higher boron (B) content of 0.0015 wt.%.

[0107] The alloys of embodiments 1 to 6 are all characterized by very good castability, good machinability, and low porosity. This demonstrates that the advantageous properties of the copper-zinc alloys described here, particularly for water-bearing components, occur over relatively wide ranges of alloying element contents. This advantageously means that, during the production of a copper-zinc alloy described here, deviations in the contents of individual alloying elements ("tolerances") do not have a significantly negative effect on the properties and suitability for the intended applications of the copper-zinc alloys according to the invention.

[0108] It shows, in a partially schematic way: Fig. 1a: Microstructure of embodiment 1 of a copper-zinc alloy according to the invention; Fig.1b: Microstructure of embodiment 2 of a copper-zinc alloy according to the invention; Fig. 1c: Microstructure of embodiment 3 of a copper-zinc alloy according to the invention; Fig. 1d: Microstructure of embodiment 4 of a copper-zinc alloy according to the invention; Fig. 1e: Microstructure of embodiment 5 of a copper-zinc alloy according to the invention; Fig. 1f: Microstructure of embodiment 6 of a copper-zinc alloy according to the invention; Fig. 1g: Microstructure of a first reference copper-zinc alloy; Fig. 1h: Microstructure of a second reference copper-zinc alloy; Fig. 1i: Microstructure of a third reference copper-zinc alloy; Fig. 2: a sanitary component according to an embodiment of the present invention in a perspective view; Fig.3: an axial or longitudinal section of the sanitary component of the Fig. 2; Fig. 4: a method for manufacturing a component according to an embodiment of the present invention.

[0109] Fig. Figure 1 shows, by way of example, the different microstructures of embodiment 1 ( Fig. 1a), of embodiment 2 ( Fig. 1b), of embodiment 3 ( Fig. 1c), of embodiment 4 ( Fig. 1d), of embodiment 5 ( Fig. 1e) and embodiment 6 ( Fig. 1f) each of a copper-zinc alloy according to the invention in comparison to a first reference copper-zinc alloy ( Fig. 1g), a second reference copper-zinc alloy ( Fig. 1h) and a third reference copper-zinc alloy ( Fig. 1i). Fig. Figure 1 shows the respective microstructures in the as-cast state, i.e., without any heat treatment being carried out on the samples.

[0110] The first reference copper-zinc alloy consists of 60 wt% copper (Cu), 0.6 wt% aluminum (Al), 0.1 wt% iron (Fe) and 0.0009 wt% boron (B), without containing manganese (Mn), phosphorus (P), tin (Sn) and silicon (Si).

[0111] The second reference copper-zinc alloy, like the first reference copper-zinc alloy, consists of 60 wt.% copper (Cu), 0.6 wt.% aluminum (Al), 0.1 wt.% iron (Fe) and 0.0009 wt.% boron (B) and additionally contains 0.6 wt.% tin (Sn), without containing manganese (Mn), phosphorus (P) and silicon (Si).

[0112] The third reference copper-zinc alloy, like the first and second reference copper-zinc alloys, consists of 60 wt.% copper (Cu), 0.6 wt.% aluminum (Al), 0.1 wt.% iron (Fe) and 0.0009 wt.% boron (B) and additionally contains 0.6 wt.% tin (Sn) and 0.4 wt.% silicon (Si), without containing manganese (Mn) and phosphorus (P).

[0113] Out of Fig. 1a, Fig.1b, Fig. 1c, Fig. 1d, Fig. 1e, Fig. As can be seen from Figure 1f, all embodiments of a copper-zinc alloy according to the invention have a fine microstructure. The microstructures of the embodiments differ only slightly from one another with regard to their grain size. This is significantly different from the microstructures described in Figure 1f. Fig. 1a, Fig. 1b, Fig. 1c, Fig. 1d, Fig. 1e, Fig. The microstructures of the exemplary embodiments of the copper-zinc alloys according to the invention shown in Figure 1f are shown. Fig. 1g, Fig. 1h, Fig. 1i, that the reference copper-zinc alloys have a significantly coarser microstructure.

[0114] Fig. 2, Fig. Figure 3 shows, by way of example, a sanitary component 10 according to an embodiment of the present invention in a perspective view based on a particularly advantageous application ( Fig. 2) or an axial or longitudinal section ( Fig. 3).

[0115] The sanitary component 10 is, by way of example, a mixer (fitting) with a known structure comprising a base body component 4, O-rings 1, 2, an adapter 3 to which at least one hose 5 is or can be connected, a mixing cartridge 6, a flow regulator 7 and a lever component 8.

[0116] The base component 4 is cast from a copper-zinc alloy according to the first aspect of the invention. It has at least one passage 9 for guiding (drinking) water. Additionally or alternatively, the lever component 8 can also be cast from a copper-zinc alloy according to the first aspect of the invention.

[0117] Accordingly, both the base body component 4 (as such) and / or the lever component 8 (as such) as well as the sanitary component 10 (with the base body component 4 and the lever component 8), which has an actuating element in the form of the mixing cartridge 6 for changing a flow through the passage 9 of the (base body component 4 of the) sanitary component 10, can each represent a (sanitary) component according to an embodiment of the present invention.

[0118] For manufacturing, the base body component 4 and / or the lever component 8 (each) are first cast from a copper-zinc alloy according to the first aspect of the invention ( Fig.4: Step S10), wherein the base body component 4 and the lever component 8 can be cast from the same or different copper-zinc alloys, or only one of the base body component 4 and the lever component 8 can be cast from a copper-zinc alloy according to the first aspect of the invention, and the other of the base body component 4 and the lever component 8 can be made from a different material, and subsequently the base body component 4 and / or the lever component 8 (each) is machined by material separation or removal, comprising, for example, milling, drilling, thread cutting, deburring, grinding and / or polishing ( Fig. 4: Step S20). Afterwards, the (respective) component 4 or 8 can be coated, for example with a chrome plating or a paint finish ( Fig. 4: Step S30). A corresponding coating is in Fig.3 is indicated by reference numeral 11. The other components mentioned above (adapter 3, mixing cartridge 6, aerator 7, etc.) can then be mounted. Fig. 4: Step S40).

[0119] Although exemplary versions were explained in the preceding description, it should be noted that a large number of variations are possible.

[0120] In particular, instead of primary forming, in the exemplary embodiment casting, or after this primary forming or casting in step S10, the base body component 4 and / or the lever component 8 can be formed from a semi-finished product made of a copper-zinc alloy according to the first aspect of the invention and optionally subsequently machined by material removal ( Fig. 4: Step S20) and / or coated ( Fig.4: Step S30). In all these cases (manufacturing the base body component 4 includes primary and / or forming and / or manufacturing the lever component 8 includes primary and / or forming), the manufacturing of the sanitary component 10 also includes primary and / or forming at least a part of the sanitary component 10 with or a semi-finished product made of a copper-zinc alloy according to the first aspect of the invention.

[0121] Furthermore, it should be noted that the exemplary embodiments are merely examples and are not intended to restrict the scope of protection, applications, or structure in any way. Rather, the preceding description provides the skilled person with a guideline for implementing at least one exemplary embodiment, whereby various modifications, particularly with regard to the function and arrangement of the described components, can be made without departing from the scope of protection as defined by the claims and these equivalent combinations of features. Reference sign 1, 2 O-rings 3 adapters 4 Basic body component 5 hoses 6 mixing cartridges 7 aerators 8 Lever component 9 Passage 10 Sanitary component 11 Coating S10 step S20 step S30 step S40 step QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] EP 2 964 798 B1

[0009] EP 2 806 044 A2

[0010] EP 572 959A1

[0011] DE 10 2013 004 081 A1

[0012] Cited non-patent literature

[0000] VDG Information Sheet P 201 of May 2002

[0004] DIN standard EN 1982:2017 as of November 2017

[0005]

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