EP0324394A2 - Process and agent for simultaneous vibratory grinding, cleaning and passivation of metallic workpieces - Google Patents

Abstract

The invention relates to a process and agent for the simultaneous vibratory grinding, cleaning and passivation of metallic workpieces using acidic aqueous solutions which contain orthophosphoric acid and/or pyrophosphoric acids and/or water-soluble salts thereof, oligocarboxylic acids and, if required, also surfactants, corrosion inhibitors and other customary active ingredients and/or auxiliaries.

Description

The invention relates to methods and means for simultaneous surface grinding, cleaning and passivating metallic workpieces.

Metallic workpieces or articles of daily use are now largely manufactured by means of industrial mass production in automated processes. The surfaces of such metal parts, which are made of steel, cast iron, copper and its alloys, aluminum and its alloys, zinc, magnesium and other metals, usually have to be subjected to a finishing process before they are sold directly, used as intended or further processed in known finishing processes will.

Metallic workpieces produced by turning, milling, casting or similar metal processing processes often have sharp cut edges or corners or also rough or scale-coated surfaces, so that deburring and rounding of the cut edges and corners, often also smoothing or polishing the entire surface, is required. Especially in processes of further processing, the quality of subsequently applied surface layers on such workpieces depends to a large extent on how good the metallic surface is for the application of such additional ver noble layers is prepared. For example, the galvanic deposition of metals on such surfaces can only proceed satisfactorily if the galvanic deposition process has been preceded by cleaning, descaling and grinding of the surface.

Metal workpieces or molded parts can be processed either by manual mechanical deburring, grinding, sanding, brushing and polishing or by a mechanical-mechanical processing method. The purely manual mechanical processing of large quantities of metallic parts, especially small metallic parts, is hardly acceptable today for reasons of economy. The mechanical-chemical processing, e.g. the so-called "slide grinding" is a process that is carried out in bell apparatus, drum apparatus, vibration machines or centrifugal machines. The workpieces are brought into contact with natural (pebbles, dolomite, quartz, etc.) or synthetic (ceramic or plastic-bonded corundum, aluminum oxide, silicon carbide or boron carbide) abrasives of various shapes under spraying with water-based compositions specially developed for surface grinding. The size and external shape (triangles, cylinders, stars, cones, spheres, etc.) and the roughness of the grinding wheels ("chips") ensure that the metal surfaces are abraded, and possibly polished. Metallic workpieces and / or moldings can be descaled, deburred, ground, smoothed, polished and polished by such a surface grinding.

The chemical treatment agents ("compounds") used in the course of the surface grinding are matched in their composition and their dosage to the metallic surfaces that are to be surface-finished, but must also take into account special features of the special vibratory finishing process. The main tasks of such treatment agents are to ensure good cleaning, dispersing and dirt-carrying capacity, so that oil and grease contamination are emulsified and the abrasion of the abrasive bodies and the workpieces is completely removed and is not deposited on the workpieces. In addition, the agents are intended to prevent corrosion of the metallic workpieces or molded parts and, moreover, to have a favorable influence on the grinding action and / or polishing action during slide grinding. For this it is necessary that the agents do not coat the molded parts with a lubricating layer during grinding, which prevent the gloss effect when polishing the molded parts. In addition, due to their composition, such abrasives can act on the grinding action of the chips, thereby making it possible to deburr and pre-grind the workpieces with the same chips and, after changing the chemical treatment agent, to carry out a fine treatment and polishing.

The agents are usually packaged in such a way that they can be concentrated in liquid form or metered in prediluted by means of automated pumps. Typically, such abrasives react neutral to weakly alkaline in water and contain combinations of washing-active and corrosion-inhibiting substances.

A disadvantage of the products known from the prior art and mostly developed purely empirically is that a differently adjusted agent had to be used for each application, ie each metallic material of the workpieces or molded parts. This necessitated a complete changeover of the vibratory finishing process when changing the workpieces to be machined using the vibratory finishing process. It was also disadvantageous that satisfactory results were only achieved with surface grinding could be achieved if the surfaces of the metallic workpieces or molded parts had been carefully cleaned and passivated before the surface grinding. Machining processes upstream of the actual vibratory grinding were therefore necessary in order to condition the metal surface in the desired shape. In addition to the fact that these upstream processing steps required separate systems and chemicals, the effect of the surface grinding agents and thus also the success of the surface grinding method was regularly adversely affected by the fact that the cleaning agents and passivating agents were introduced into the equipment for surface grinding. As a result, the compounds were only able to develop their effects to a limited extent during slide sleeping.

Surprisingly, it has now been found that when powdery or liquid agents are used, it is possible to combine the individual process steps of surface grinding, cleaning and passivating in one process step by immersion or spraying process and to use only one agent for this which has a cleaning and passivating effect and also promotes the finishing process. This has made it possible to avoid the technical disadvantages of a three-step process using three differently composed solutions.

The invention relates to a method for simultaneous vibratory grinding, cleaning and passivating metallic workpieces, which is characterized in that the workpieces are brought into contact with aqueous solutions having a pH in the range from 1 to 6, the orthophosphoric acid and / or pyrophosphoric acids and / or their water-soluble salts, one or more oligocarboxylic acids, and optionally one or more surfactants, one or more corrosion inhibitors as well as other active ingredients and / or auxiliaries per se common in cleaning, passivating and lubricating abrasives.

The invention also relates to agents for simultaneous vibratory grinding, cleaning and passivating metallic workpieces, the orthophosphoric acid and / or pyrophosphoric acids and / or their water-soluble salts, one or more oligocarboxylic acids, and optionally one or more surfactants, one or more corrosion inhibitors, and optionally further, in Detergents, passivation agents and vibratory abrasives contain active substances and / or auxiliaries which are customary per se and, if appropriate, water.

The method according to the invention and the means used in this method for simultaneous surface grinding, cleaning and passivating metallic workpieces can be applied to metallic workpieces and / or molded parts of the most varied composition. So it is possible in the course of the process workpieces or molded parts made of iron and all its alloys, for example steels of different compositions, cast iron, etc., copper and its alloys, for example brass, bronze etc., aluminum alloys, zinc or magnesium or other metals or Treat alloys. The surprising thing about the present method is that not only the actual mechanical-chemical surface treatment of the surface grinding, which is usually carried out in drums or vibrators, can be carried out using these solutions. Rather, the usually upstream step of cleaning the metallic workpieces or molded parts and passivating the respective metallic surface is carried out with the same solutions in the same process without the need for additional systems or treatment solutions. The respective metallic surface is cleaned, descaled, passivated, deburred, ground, smoothed, polished and polished in one step.

For this purpose, according to the invention, the workpieces are brought into contact with aqueous solutions which have a pH in the range from 1 to 6. Solutions which have a pH in the range from 3.5 to 5 are preferably used. Depending on the system, contact with the workpieces or molded parts takes place by immersion or spraying. The aqueous solutions according to the invention are usually applied in the present process by spraying the workpieces or molded parts in the systems (drums, vibrators, etc.) in which they are moved together with the grinding wheels, with the aqueous solutions and these between the workpieces and run through the grinding wheels to the bottom of the respective system. The solutions are in contact with the grinding wheel surfaces and metallic surfaces. They also remove the dirt detached in the cleaning process and the metal particles and / or abrasive particles detached in the tumble grinding process, are freed of such contaminants after exiting the system and brought back into contact with the workpieces and molded parts.

In the process according to the invention, the workpieces and molded parts are brought into contact with aqueous solutions which contain orthophosphoric acid and / or pyrophosphoric acids and / or their water-soluble salts as one of the essential components. "Pyrophosphoric acids" are understood to mean all those compounds which have arisen from the condensation of several phosphate groups on one another. It corresponds to a preferred embodiment of the process according to the invention that alkali metal salts and / or ammonium salts of orthophosphoric acid and / or pyrophosphoric acids are used as phosphate components. The alkali metal salts are therefore the lithium salts, sodium salts, potassium salts, rubidium salts or cesium salts, of which the potassium salts and especially the sodium salts are preferred due to their ready availability are moving. As ammonium salts, both those with an NH₄⁺ cation and also those ammonium salts which carry one or more organic substituents on the nitrogen atom can be used. Of such organoammonium compounds, those which carry one or more alkyl radicals with a straight-chain or branched chain and 1 to 6 carbon atoms in the alkyl radical are particularly preferred. Of the ammonium salts, the NH₄⁺ salts are particularly preferred and can advantageously be used as phosphate components in the aqueous solutions which are used in the process according to the invention.

In a preferred embodiment of the process according to the invention, the workpieces are brought into contact with acidic aqueous solutions which contain one or more of the phosphate components mentioned in amounts of 0.2 to 10% by weight. The weight data are based on the finished application solution and indicate the active substance content which is used in such application solutions.

The inventive method for simultaneous surface grinding, cleaning and passivating metallic workpieces is further characterized in that the workpieces or molded parts are brought into contact with aqueous solutions which contain one or more oligocarboxylic acids as a further essential component. According to the invention, individual compounds or mixtures of dicarboxylic acids or tricarboxylic acids are preferably used as such. According to a further preferred embodiment of the process, these can be substituted with polar groups in the alkylene radical. Hydroxy groups are primarily suitable as polar substituents. Particular preference is given to using dicarboxylic acids or tricarboxylic acids, tartaric acid or citric acid or mixtures of these two carboxylic acids in the process.

It is a further preferred embodiment of the method to use such aqueous solutions for simultaneous surface grinding, for cleaning and passivation of metallic workpieces, which contain one or more of the carboxylic acid components mentioned in amounts of 0.01 to 1% by weight. As in the case of the phosphate components, this is also based on the active substance content in the finished application solutions.

A further component of the aqueous solutions used in the process according to the invention are, where appropriate, surfactants, it also being possible here for the aqueous solutions to contain one or more surfactants as surface-active components. In preferred embodiments, individual compounds or mixtures of exclusively nonionic surfactants or instead combinations of one or more nonionic surfactants with one or more anionic or alternatively one or more cationic surfactants are suitable. Due to the good cleaning properties and the fact that such solutions promote the tumbling process in a special way, aqueous solutions are particularly preferred in the process according to the invention, the combinations of one or more nonionic surfactants with one or more anionic or alternatively with one or more cationic surfactants contain. Combinations in which nonionic and anionic or alternatively cationic surfactants are present in a ratio of 1: 1 to 10: 1 can be used with particular advantage. The total amounts of the surfactants contained in the aqueous solutions used are in the range from 0 to 2% by weight, preferably in the range from 0.005 to 2% by weight, according to the process of the invention. This information also relates to the active substance content in the application solution.

The process also provides that the aqueous treatment solutions optionally contain one or more corrosion inhibitors. Corrosion inhibitors of this type are to be matched to the metal from which the metallic workpieces or molded parts are made, which are to be cleaned, passivated and, at the same time, subjected to vibratory grinding according to the inventive method. Aqueous solutions are preferably used in which one or more compounds from the group of alkali metal molybdates, preferably sodium molybdates, benzotriazole, tolyltriazole and benzothiazole, are used as corrosion inhibitor components. Corrosion inhibitors of this type, which, like the other components, can be used alone or in combination of several components acting in the same direction, are present in amounts of 0 to 0.02% by weight and preferably in total amounts of 0.001 to 0.02% by weight. -% in front. As with the other components, this information is based on the active substance content in the application solution.

The process can be carried out using such acidic aqueous solutions which, in addition to the components described generally or in more detail above, also contain other active substances and / or auxiliaries which are customary per se. Such active ingredients can be, for example, water hardness stabilizers. Their use is particularly advantageous if the treatment agents were mixed with water in the process, which contains large amounts of hardness formers, in particular alkaline earth metal carbonates. Such water hardness stabilizers are, for example, phosphonic acids or their derivatives, such as, for example, hydroxyethane diphosphonic acid (HEDP) or phosphonobutane tricarboxylic acid (PBTC) or their water-soluble salts, but also ethylenediaminetetraacetic acid or its water-soluble salts, nitrilotriacetic acid and its water-soluble salts or else for such purposes Connections known in the art. These are present in amounts of 0 to 0.2% by weight and preferably - if their co-use is desired - in amounts of 0.01 to 0.2% by weight and allow the use of "hard" in the process according to the invention. Waters.

As already described above, in the process according to the invention, such aqueous solutions are usually brought into contact with the metallic workpieces or molded parts by dipping or spraying. This involves simultaneous surface grinding, cleaning and passivating the surfaces of the workpieces. This is usually carried out at temperatures in the range from 20 to 60 ° C., but preferably at room temperature. The treatment times depend very much on the degree of soiling, the thickness of the burrs or protrusions to be removed, the hardness, size and shape of the abrasive bodies and also on the properties of the aqueous treatment solutions. In preferred embodiments of the method, they are in the range between 10 and 60 minutes. Usually the surface treatment is followed only by a drying process. This drying process can be carried out using conventional aids, such as, for example, corn meal, wood flour, etc., at room temperature using the drum method or using warm air. In special cases, however, a rinse can also be provided before the drying process. This essentially depends on the type of further treatment of the workpieces or molded parts treated according to the method according to the invention.

The invention also includes the means used in the method described in more detail above for simultaneous surface grinding, cleaning and passivating metallic workpieces or molded parts. These contain orthophosphoric acid and / or pyrophosphoric acids and / or their water-soluble salts and one or more oligocarboxylic acids, and optionally one or more surfactants, one or more corrosion inhibitors, as well as other active substances and / or auxiliaries which are customary per se in cleaning, passivating and surface grinding agents. The agents can thus either be packaged in powder form and packaged as such and stirred into water at the application site with little effort, or they are prepared in the form of highly concentrated aqueous solutions and merely diluted at the application site. The former has the advantage that only the pure substance is transported, thus avoiding unnecessary water transport. However, the latter is more advantageous because liquid concentrates can be metered in automatically at the application site by means of metering pumps and thus make handling easier for the user. The aqueous solutions which come on the market in the form of concentrates are homogeneous. Due to the components they contain, aqueous concentrates have a pH in the range from 1 to 6. The pH value is preferably in the range from 3.5 to 5. However, if the pH value is not in this range due to the use of more alkaline components, it can optionally be added by adding non-corrosive acids, preferably for example phosphoric acids, phosphonic acids, phosphonocarboxylic acids or Carboxylic acids. However, a pH adjustment is usually not necessary. The aqueous application solutions are usually used with an active substance content in the range from approximately 0.2 to approximately 14% by weight.

The agents according to the invention for simultaneous surface grinding, cleaning and passivating metallic workpieces contain, as phosphate components, alkali metal salts and / or ammonium salts of orthophosphoric acid and / or pyrophosphoric acids. Preferred phosphate components in the agents according to the invention are acidic sodium phosphates and / or sodium pyrophosphates.

Further essential components of the agents according to the invention are oligocarboxylic acids. From this group, either a single compound or a mixture of several compounds, i.e. a mixture of several dicarboxylic acids or a mixture of several tricarboxylic acids or also a mixture of one or more dicarboxylic acids and tricarboxylic acids may be contained in the compositions. Dicarboxylic acids and / or tricarboxylic acids substituted with polar groups are preferably used. From the group of such compounds, tartaric acid and citric acid are particularly preferred as carboxylic acid components.

Another component of the agents according to the invention are tensides. These can also be represented as individual compounds or in a mixture of several surfactants. The following combinations are preferred as surfactant components in the agents according to the invention: Either one or more nonionic surfactants can be used as surfactant components, or the agents can be combinations of one or more nonionic surfactants with one or more anionic surfactants or alternatively combinations of one or more nonionic surfactants with one or contain more cationic surfactants. In such combinations of several surfactants of different chemical structure, which are particularly advantageous in the agents according to the invention and produce an excellent cleaning effect, combinations of nonionic surfactants with anionic or cationic surfactants in a ratio of 1: 1 to 1:10 are particularly preferred.

A large number of compounds known per se from the prior art as surfactants are suitable as surfactants for the agents according to the invention. For example, addition products of ethylene oxide and / or propylene oxide with fatty alcohols or fatty amines, ie alcohols and / or or amines which carry 6 to 18 carbon atoms in the straight-chain or branched-chain alkyl radical. Polyalkylene glycol ethers of the general formula below are also suitable as nonionic surfactants
R'-O - [(CH₂) _m -O] _n -R˝
in the
R ′ is a straight-chain or branched alkyl radical having 8 to 18 carbon atoms,
R˝ is an alkyl radical with 4 to 8 carbon atoms,
m is a number from 2 to 4 and
n is a number from 7 to 12.

Such polyalkylene glycol ethers are weakly foaming nonionic surfactants, in some cases. even known as a pronounced defoamer and therefore particularly well suited.

If anionic surfactants are used in the agents according to the invention, these can be, for example, fatty alcohol ether sulfate and / or fatty alcohol ether sulfonates derived from the fatty alcohols defined in more detail above. In addition, fatty acids and their water-soluble salts and also naphthalenesulfonic acid or their water-soluble salts are also suitable as anionic surfactants.

Cationic surfactants which are used in the preferred embodiments of the agents according to the invention in combination with nonionic surfactants are usually ammonium compounds which contain one or more alkyl residues, aryl residues or aralkyl residues with more than 6 C atoms. Such ammonium compounds usually have at least one straight-chain alkyl radical with more than 12 C atoms, preferably with 14 to 18 C atoms. The anions of such ammonium salts are usually anions of non-corrosive acids. Examples of such compounds are lauryldimethylbenzylammonium salts, benzyltrimethylammonium salts, trialkylhydroxyalkylammonium salts (such as, for example, butyldimethyl-2-hydroxydodecylammonium benzoate or bis- (benzyldimethyl-2-hydroxydodecylammonium) succinate or N-benzyldimzoium 1-ammonium (1) -hydroxyldimethyl-iodoniumammonium (1-hydroxyldimbenzylammonium) (n-hydroxyldimbenzylammonium) (n-hydroxyldimbenzyl) ammonium (1) as well - and 2-position substituted derivatives).

The agents according to the invention can optionally also contain one or more corrosion inhibitors. These are usually matched to the respective specific application problem and are therefore based on the metallic surfaces that are to be cleaned, passivated and slip-treated. Suitable corrosion inhibitors can also be used with one another, which has the advantage that the agents according to the invention can thereby be used for a larger number of applications. Compounds from the group alkali metal molybdates, preferably sodium molybdates, benzotriazole, tolyltriazole and benzothiazole, are preferably used as corrosion inhibitors.

In addition, agents according to the invention can also contain further active ingredients and / or auxiliaries which are customary in cleaning, passivating and vibratory abrasives. Such additional active ingredients, which are also used in preferred embodiments of the agents according to the invention, are water hardness stabilizers. As such, individual compounds or combinations from the group of the phosphonic acid derivatives (such as, for example, hydroxyethyldiphosphonic acid, phosphonobutane tricarboxylic acid or its water-soluble salts), ethylenediaminetetraacetic acid and its salts and nitrilotriacetic acid and its water-soluble salts can be used.

As already explained in more detail above, the agents according to the invention can be used as powder, i.e. as 100% active substance or as concentrates.

• (a) Orthophosphorsäure und/oder Pyrophosphorsäuren und/oder deren wasserlösliche Salze in Mengen von 50 bis 98 Gew.-%,
• (b) eine oder mehrere Oligocarbonsäure(n) in Mengen von 1 bis 10 Gew.-%,
• (c) gegebenenfalls ein oder mehrere Tensid(e) in Mengen von 0 bis 20 Gew.-%, vorzugsweise von 0,1 bis 20 Gew.-%,
• (d) gegebenenfalls einen oder mehrere Korrosionsinhibitoren in Mengen von 0 bis 0,5 Gew.-%, vorzugsweise von 0,01 bis 0,5 Gew.-%,
• (e) gegebenenfalls weitere, in Gleitschleif-, Reinigungs- und Passivierungsmitteln an sich übliche Wirkstoffe und/oder Hilfsstoffe in Mengen von 0 bis 20 Gew.-%, vorzugsweise von 1 bis 20 Gew.-%.

In a preferred embodiment of the invention, the agents according to the invention are in powder form and have the following composition:

• (a) orthophosphoric acid and / or pyrophosphoric acids and / or their water-soluble salts in amounts of 50 to 98% by weight,
• (b) one or more oligocarboxylic acid (s) in amounts of 1 to 10% by weight,
• (c) optionally one or more surfactant (s) in amounts of 0 to 20% by weight, preferably 0.1 to 20% by weight,
• (d) optionally one or more corrosion inhibitors in amounts of 0 to 0.5% by weight, preferably 0.01 to 0.5% by weight,
• (e) if appropriate, further active substances and / or auxiliaries which are customary per se in surface grinding, cleaning and passivating agents in amounts of from 0 to 20% by weight, preferably from 1 to 20% by weight.

• (a) Orthophosphorsäure und/oder Pyrophosphorsäuren und/oder deren wasserlösliche Salze in Mengen von 10 bis 50 Gew.-%,
• (b) eine oder mehrere Oligocarbonsäure(n) in Mengen von 0,5 bis 5 Gew.-%,
• (c) gegebenenfalls ein oder mehrere Tensid(e) in Mengen von 0 bis 10 Gew.-%, vorzugsweise von 0,2 bis 10 Gew.-%,
• (d) gegebenenfalls einen oder mehrere Korrosionsinhibitoren in Mengen von 0 bis 0,1 Gew.-%, vorzugsweise von 0,01 bis 0,1 Gew.-%,
• (e) gegebenenfalls weitere, in Gleitschleif-, Reinigungs- und Passivierungsmitteln an sich übliche Wirkstoffe und/oder Hilfsstoffe in Mengen von 0 bis 1 Gew.-%, vorzugsweise von 0,05 bis 1 Gew.-%,
• (f) Wasser in solchen Mengen, die die Mengen der oben genannten Komponenten (a) bis (e) zu 100 Gew.-% ergänzen.

In a further, likewise preferred embodiment of the invention, the compositions according to the invention are present as aqueous concentrates, ie that such concentrates also contain water to the active substances, which adds up to 100% by weight of the total amount of all components. These aqueous concentrates have the following composition:

• (a) orthophosphoric acid and / or pyrophosphoric acids and / or their water-soluble salts in amounts of 10 to 50% by weight,
• (b) one or more oligocarboxylic acid (s) in amounts of 0.5 to 5% by weight,
• (c) optionally one or more surfactant (s) in amounts of 0 to 10% by weight, preferably 0.2 to 10% by weight,
• (d) optionally one or more corrosion inhibitors in amounts from 0 to 0.1% by weight, preferably from 0.01 to 0.1% by weight,
• (e) if appropriate, further active substances and / or auxiliaries which are customary in slide grinding, cleaning and passivating agents in amounts of from 0 to 1% by weight, preferably from 0.05 to 1% by weight,
• (f) Water in amounts which add up to 100% by weight of the amounts of components (a) to (e) mentioned above.

Such concentrates are then diluted with additional water at the application site or the powdered products are dissolved in water. As already explained above, the application solutions have an active substance content in the range from approximately 0.2 to approximately 14% by weight. The total amounts of the components specified above in detail are thus mixed with an amount of water which adds up to 100% by weight of the total amount of all components. Depending on the individual components used, pH values are usually in the range from 1 to 6, preferably from 3.5 to 5. If, in the application solutions according to the invention, this pH value is not achieved solely by the specified components, further acids can optionally be added. However, these acids must not be corrosive and preferably come from the group of phosphoric acids, phosphonic acids, phosphonocarboxylic acids and carboxylic acids.

The invention is illustrated by the following examples.

Workpieces or molded parts made of iron, brass, aluminum alloys with the composition AlSi₁₇Cu₄Mg (silumin), bronze, copper, a magnesium alloy with the composition MgMn₂ and Zinc was taken directly from production and cleaned, surface passivated and ground in a single operation in a vibration system using various grinding media (ceramic, plastic-bonded corundum) with the addition of the test solutions described below in the examples. After the one-step surface treatment, the workpieces were partially rinsed with tap water (approx. 15 ° d) and dried with corn grist or warm air (100 ° C). The surfaces were then assessed visually.

example 1

An application solution with the following composition was used:
98% H₂O;
0.63% Na₂H₂P₂O₇;
1.17% NaH₂PO₄;
0.08% citric acid;
0.06% of an adduct of 12 moles of ethylene oxide (EO) with coconut amine;
0.06% of a C₁₂ to C₁₈ fatty alcohol 9.1 EO-butyl ether.

The metal parts were degreased, passivated and deburred at 20 ° C. for 20 minutes under the action of this solution, which had a pH of 3.5. The result of this one-step process showed that very good degreasing and passivation had taken place and that the production-related metal burrs had been completely removed. The steel parts showed a bluish-iridescent passivation layer. The surfaces of the non-ferrous metals were, without exception, bare and smooth and showed no corrosion or contact points.

Even after storage for several weeks in medium humidity, corrosion on the metallic surfaces could not be determined.

At this point, it should be emphasized again that the present process is a one-step process in which, in a practical operation, both degreased and deoxidized / passivated, as well as deburring in vibratory grinding, are possible.

Example 2

In accordance with the procedure described above in Example 1, the moldings were treated with an aqueous solution of the following composition, which had a pH of 3.7:
98.096% H₂O;
1.40% NaH₂PO₄;
0.108% tartaric acid;
0.06% phosphonobutane tricarboxylic acid;
0.20% naphthalenesulfonic acid;
0.012% of an addition product of 12 moles of ethylene oxide (EO) with coconut amine;
0.12% of a C₁₂ to C₁₈ fatty alcohol 9.1 EO-butyl ether and
0.004% Na₂MoO₄.

The moldings were brought into contact with such an aqueous solution (sprayed) at 25 to 30 ° C. for 40 minutes. This showed excellent degreasing, passivation and deburring performance. The steel parts had a bluish-iridescent passivation layer. Molded parts made of brass and copper had a bare surface and were oxide free. Aluminum alloys also had a bare surface.

Example 3

In the manner given in Examples 1 and 2, metallic moldings were brought into contact with aqueous solutions during surface grinding which had the following composition:
94.85% H₂O;
1.57% Na₂H₂P₂O₇;
2.93% NaH₂PO₄;
0.10% citric acid;
0.10% tartaric acid;
0.15% of an addition product of 12 moles of ethylene oxide (EO) with coconut amine;
0.15% of a C₁₂ to C₁₈ fatty alcohol 9.1 EO-butyl ether and
0.15% lauryldimethylbenzylammonium chloride.

As in the preceding examples, the weight data here relate to the active substance content of the respective components in the application solution.

The molded parts or metal surfaces were treated with such a solution at 20 to 30 ° C. for 15 minutes. This showed complete degreasing or cleaning and very good passivation of the metallic surface layer. In addition, slide grinding in the presence of such aqueous solutions led to deburring that fully complied with practical requirements.

The metal pieces or molded parts were rinsed with water and then dried using warm air. After that, steel parts showed a bluish-iridescent passive layer with good long-term rust protection. Molded parts made of brass and buyer were bare and oxide-free on the surface. Molded parts made of aluminum or its alloys remained shiny metallic.

Claims (19)

1. A method for simultaneous vibratory grinding, cleaning and passivating metallic workpieces, characterized in that it is brought into contact with workpieces with aqueous solutions having a pH in the range from 1 to 6
(a) orthophosphoric acid and / or pyrophosphoric acids and / or their water-soluble salts,
(b) one or more oligocarboxylic acids,
(c) optionally one or more surfactants,
(d) optionally one or more corrosion inhibitors and
(e) if appropriate, further active substances and / or auxiliaries which are customary per se in cleaning, passivating and vibratory abrasives
contain. 2. The method according to claim 1, characterized in that the workpieces are brought into contact with aqueous solutions which have a pH of 3.5 to 5. 3. Process according to claims 1 and 2, characterized in that alkali metal salts and / or ammonium salts of orthophosphoric acid and / or pyrophosphoric acids, preferably acidic sodium phosphates and / or sodium pyrophosphates, are used as the phosphate component. 4. The method according to claims 1 to 3, characterized in that one uses the phosphate component (s) in amounts of 0.2 to 10 wt .-%, based on the active substance content in the application solution. 5. The method according to claim 1, characterized in that one or more dicarboxylic acids and / or tricarboxylic acids, preferably with polar groups substituted dicarboxylic acids and / or tricarboxylic acids, particularly preferably tartaric acid and / or citric acid, are used as oligocarboxylic acids. 6. The method according to claims 1 and 5, characterized in that the carboxylic acid component (s) in amounts of 0.01 to 1 wt .-%, based on the active substance content in the application solution, is used. 7. The method according to claim 1, characterized in that one or more nonionic surfactants or combinations of one or more nonionic surfactants with one or more anionic surfactants or with one or more cationic surfactants is used as the surfactant component, the nonionic with anionic or cationic surfactants in Quantity ratio 1: 1 to 10: 1 are available. 8. The method according to claims 1 and 7, characterized in that the surfactant component (s) in total amounts from 0 to 2.0 wt .-%, preferably from 0.005 to 2 wt .-%, based on the active substance content in the application solution, starts. 9. The method according to claim 1, characterized in that one or more compounds from the group of alkali metal molybdates, benzotriazole, tolyltriazole and benzothiazole are used as corrosion inhibitors. 10. The method according to claims 1 and 9, characterized in that the corrosion inhibitor component (s) in total amounts of 0 to 0.02 wt .-%, preferably from 0.001 to 0.02 wt .-%, based on the active substance content in the application solution. 11. The method according to claim 1, characterized in that water hardness stabilizers such as phosphonic acids and / or their derivatives, ethylenediaminetetraacetic acid and its water-soluble salts, or nitrilotriacetic acid and its water-soluble salts, in amounts of 0 to 0.2% by weight, as additional active ingredients, preferably from 0.01 to 0.2% by weight, based on the active substance content in the application solution. 12. Containing agents for simultaneous surface grinding, cleaning and passivating metallic workpieces (a) orthophosphoric acid and / or pyrophosphoric acids and / or their water-soluble salts, (b) one or more oligocarboxylic acids, (c) optionally one or more surfactants, (d) optionally one or more corrosion inhibitors, (e) if appropriate, further active substances and / or auxiliaries which are customary per se in cleaning, passivating and sliding abrasives and (f) optionally water. 13. Composition according to claim 12, containing as phosphate component alkali metal salts and / or ammonium salts of orthophosphoric acid and / or pyrophosphoric acid (s), preferably acidic sodium phosphates and / or sodium pyrophosphates. 14. Composition according to claim 12, containing as oligocarboxylic acid one or more dicarboxylic acid and / or tricarboxylic acids, preferably dicarboxylic acids and / or tricarboxylic acids substituted with polar groups, particularly preferably tartaric acid and / or citric acid. 15. Composition according to claim 12, containing one or more nonionic surfactants or combinations of one as a surfactant component or more nonionic surfactants with one or more anionic surfactants or with one or more cationic surfactants, the nonionic surfactants with anionic or with cationic surfactants being present in a ratio of 1: 1 to 10: 1. 16. Composition according to claim 12, containing as corrosion inhibitors one or more compounds from the group alkali metal molybdates, benzotriazole, tolyltriazole and benzothiazole. 17. Composition according to claim 12, containing water hardness stabilizers as additional active ingredients. 18. Composition according to claims 12 to 17, containing (a) orthophosphoric acid and / or pyrophosphoric acids and / or their water-soluble salts in amounts of 50 to 98% by weight, (b) one or more oligocarboxylic acids in amounts of 1 to 10% by weight, (c) optionally one or more surfactants in amounts of 0 to 20% by weight, preferably 0.1 to 20% by weight, (d) optionally one or more corrosion inhibitors in amounts of 0 to 0.5% by weight, preferably 0.01 to 0.5% by weight, (e) optionally further active substances and / or auxiliaries which are conventional per se in cleaning, passivating and vibratory abrasives in amounts of from 0 to 20% by weight, preferably from 1 to 20% by weight. 19. Composition according to claims 12 to 17, containing (a) orthophosphoric acid and / or pyrophosphoric acids and / or their water-soluble salts in amounts of 10 to 50% by weight, (b) one or more oligocarboxylic acids in amounts of 0.5 to 5% by weight, (c) optionally one or more surfactants in amounts of 0 to 10% by weight, preferably 0.2 to 10% by weight, (d) optionally one or more corrosion inhibitors in amounts from 0 to 0.1% by weight, preferably from 0.01 to 0.1% by weight, (e) if appropriate, further active substances and / or auxiliaries which are customary in cleaning, passivating and vibratory abrasives in amounts of from 0 to 1% by weight, preferably from 0.05 to 1% by weight, (f) water in amounts which add up to 100% by weight of the total amounts of components (a) to (e).