DE102010061381A1 - Corrosion test for brake dust and/or road salt influence on vehicle components, involves applying sprayable composition comprising kaolin treated with copper and/or iron powder, and brine, and examining stress corresponding to humidity - Google Patents

Abstract

A sprayable composition is applied to a test sample and the stress effect is examined with standard usage corresponding to period and air humidity. The composition comprises a mixture of solids, in particular, kaolin treated with copper and/or iron powder, and brine.

Description

The invention relates to a corrosion test for a brake dust and / or road salt influence on vehicle parts according to claim 1.

Generic corrosion tests are known from the prior art.

In the WO 2007/28511 A2 For checking new rim coatings, a brake dust test is used in which brake dust is mixed with water. The pore body is then exposed to defined environmental conditions.

The DE 102 41 878 A1 relates to vehicle cleaners which contain one or more selected components with complexing properties, their use for the removal of firmly adhering residues containing metal dust and / or metal abrasion as well as for the cleaning of rims, the production of corresponding vehicle cleaning solutions, and a method for particularly surface-sparing vehicle cleaning.

Particularly in the automotive sector, deterioration of surfaces on external construction and trim parts due to brake dust, which leads to customer complaints, is becoming increasingly common. In order to reduce warranty and goodwill and avoid image damage, it makes sense to check the sensitivity of surfaces with a suitable test method at an early stage of development.

The object of the invention is to propose an improved test method compared to the prior art.

This object is achieved by a corrosion test with the features of claim 1.

Further advantageous features include the subclaims.

According to the invention, a corrosion test is provided for a brake dust and / or road salt influence on vehicle parts, which can be mixed by applying a sprayable test mass to a sample body mixed with solid, in particular kaolin mixed with copper and / or iron powder and / or copper and / or iron. Ions and a saline solution, and testing the action of the order over a period of time and humidity commensurate with practical customer demand. In particular, as a test mass a characteristic brake dust (for example, residues that occur at brake testers) mixed with normalized mud (for example, mixture of kaolin and sand) and salts (NaCl or mixed salt, electrolyte) is provided, which is mixed with water to a slurry, the test mass can then be applied to a specimen (such as test plate or construction or vehicle part) in a defined amount (ratio amount / area).

For example, a mixing ratio of the test mass in the range of 3: 5 (solids mass [g]: saline solution [ml]) is envisaged. This mixing ratio has been proven in attempts to set a well-to-process consistency and should not be changed taking into account the resulting ratio pollutants (salts and metals) to the carrier medium (especially kaolin).

The test mass can be applied, for example, by means of a flat bristle brush (width, for example, between 1 cm and 5 cm) or, preferably, by spraying, such that a closed film is formed on the surface above the surface to be tested. The result (eg layer thickness) is strongly dependent on the nature of the surface (roughness, etc.).

Preferably, the corrosion test takes place at an air humidity of about 80% for a test period in the range of 1 to 6 weeks or about 1000 test hours. In this way it is ensured that the test mass does not dries or runs off. In addition, these conditions correspond to the mean relative humidity range that often occurs in Europe and North America.

For example, the corrosion test can be carried out at a temperature of about 40 ° in a climatic chamber in which the specimens can be stored. A corrosion test carried out in a climatic chamber is subject to optimum test conditions, especially with regard to temperature stability.

For example, the corrosion test can be carried out cyclically. In this case, for example, different test sections (for example, load cycles C and B) can be used for climate load. For example, a week can consist of seven load cycles in the following order:
CBCCCCC (7 days)

In particular, the medium (test mass) is composed of solid (kaolin mixed with copper powder (Cu) and iron powder (Fe) and / or Cu and Fe ions and a salt solution (deionized water with calcium chloride dihydrate and / or copper nitrate). Trihydrate and / or iron chloride hexahydrate), which simulates real brake dust, which can be very undefined.

In the following, some exemplary mixing ratios for differently concentrated media are given. The following mixture examples are always based on the following quantities of salt or metal powder: Salts: Calcium chloride dihydrate 3 g Copper nitrate trihydrate 0.1 g Iron chloride hexahydrate 0.4 g Metal powder (or Cu and / or Fe ions): copper powder 0.1 g iron powder 0.1 g Mixing examples (V00 ... V2): V05 3.75 g Kaolin + 6.25 ml deionized water V04 7.5 g Kaolin + 12.5 ml deionized water V03 15 g Kaolin + 25 ml deionized water V00 30 g Kaolin + 50 ml deionized water V0 60 g Kaolin + 100 ml deionized water V1 90 g Kaolin + 150 ml of deionized water V2 120 g Kaolin + 200 ml of deionized water

With these amounts exemplified here, a very large amount of medium is formed. If less medium is required, all the above quantities should be reduced in the same ratio.

This results in a manageable consistency (spreadable, not too liquid, adherent to surfaces) with the addition of 35 g of saline solution based on 100 g.

A preferred procedure envisages applying the test compound to the sample body by means of a spray gun or spray gun. The test mass is atomized for example by means of compressed air (compressor) and / or a pump and applied to the object to be coated ("sprayed"). Compared to manual application with the brush, the efficiency can be increased by using a spray gun. The atomization of the test mass also allows a much better surface quality to be achieved.

For example, to carry out the corrosion test, a sample body representing the vehicle original part (for example a wheel rim) with previously introduced damages may be provided. For example, the sludge or the test mass can be applied to the damaged (rockfall and / or scratch or notch) sample or component surfaces.

Another procedure provides that for carrying out the corrosion test, a sample body representing the original vehicle part (for example a wheel rim) can be provided without previously introduced damage.

Examples of achievable spray patterns and a spray or spray gun suitable for applying a test compound will now be shown with reference to the individual drawings.

Show it:

1 a schematic representation of a fine spray pattern;

2 a schematic representation of a coarse spray pattern;

3 a schematic representation of an even coarser spray pattern;

4 the exemplary representation of a suitable for applying a test mass spray gun.

The 1 to 3 show examples of achievable spray patterns 1 to 3 , where the 1 a fine spray picture 1 . 2 a rough spray picture 2 such as 3 an even coarser spray pattern 3 represent. With the valve technology of the spray gun, the spray properties are determined. For the different uses or compositions different spray patterns are needed, each with special characteristics. One of the important features is the droplet size, which determines how the sprayed test mass feels and what effect it achieves.

4 shows a suitable for applying a test mass and known from the prior art spray gun 4 ,

• – Zentrale Druckluftversorgung auf 4 bar einstellen
• – Becherinnendruck auf 0,25 bar einstellen (Bezugszeichen 5)
• – Stufenlosen Rund/Breitstrahlregler auf geschlossene Position drehen (Bezugszeichen 6)
• – Gegenmutter der Materialmengenregulierung drehen bis Markierung sichtbar ist (Bezugszeichen 7)
• – Pressluftmikrometer geschlossen bzw. waagerecht (Bezugszeichen 8)

For example, a fine spray pattern gem. 1 To achieve this, it is recommended to set the spray gun as follows:

• - Set the central compressed air supply to 4 bar
• - Set the cup internal pressure to 0.25 bar (reference numeral 5 )
• - Turn stepless round / wide jet regulator to closed position (reference numeral 6 )
• - Turn the counter nut of the material quantity regulator until the marking is visible (reference numeral 7 )
• - Compressed air micrometer closed or horizontally (reference numeral 8th )

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2007/28511 A2 [0003]
• DE 10241878 A1 [0004]

Claims (10)

Corrosion test for a Bremsstaub- and / or Streusalzeinfluss on vehicle parts, characterized by application of a sprayable test mass to a sample body, mixed from solid, especially kaolin mixed with copper and / or iron powder, and a salt solution and testing the impact of the contract on a practical customer demand appropriate period and humidity. Corrosion test according to claim 1, characterized by a mixing ratio of the test mass in the range of 3: 5 (solids mass [g]: saline solution [ml]) Corrosion test according to claim 1 and / or 2, characterized by a humidity in the range of 80% and a test duration in the range of 1 to 6 weeks. Corrosion test according to at least one of the preceding claims, characterized by a corrosion test placed in a climatic chamber with a temperature in the region of 40 °. Corrosion test according to at least one of the preceding claims, characterized by a salt solution of deionized water with calcium chloride dihydrate. Corrosion test according to at least one of the preceding claims, characterized by a salt solution of deionized water with copper nitrate trihydrate. Corrosion test according to at least one of claims 1 to 5, characterized by a salt solution of deionized water with iron chloride hexahydrate. Corrosion test according to at least one of claims 1 to 5, characterized by a solid mass of kaolin mixed with copper powder and / or iron powder and / or copper and / or iron ions, in particular brake dust. Corrosion test according to at least one of the preceding claims, characterized by a vehicle body representing the original sample body with previously introduced damage. Corrosion test according to at least one of Claims 1 to 8, characterized by a sample body representing the original vehicle part without damage previously introduced.

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