Brake system

Abstract

To provide a friction lining that can ensure a sufficiently large friction value when combined with an Al-containing brake disc or the like. The present invention relates to the use of a friction lining containing more than 5% by weight of aluminum in the form of aluminum metal or in the form of an aluminum alloy as a friction lining for an aluminum-containing brake disc or rotor.

Description

[Technical field]

[0001] The present invention relates to a friction lining and a corresponding friction lining mixture, which is particularly suitable for use in disc brakes having aluminum brake discs or rotors. In particular, the present invention relates to the use of an aluminum-containing friction lining in combination with an aluminum-containing brake disc or rotor. [Background technology]

[0002] In the course of a significant increase in the use of vehicles with recuperation, especially passenger cars, the idea of ​​using aluminum as a material for brake discs or as a component of brake discs has been attracting attention again in the automotive industry. The use of aluminum in brake discs not only offers weight advantages, since the thermal loads on the brake discs of said vehicles no longer reach the values ​​in conventional drives.

[0003] The prior art describes various friction lining formulations that are said to be suitable for use in combination with aluminum brake discs.

[0004] For example, DE 69403791 T2 describes a friction lining composition for rotors made of aluminum-metal matrix composites, which prevents the rotor from collapsing during braking. In this case, it is furthermore to be adjusted to an average friction coefficient of 0.38 to 0.42. The friction lining mixture contains 2 to 12% by weight of porous copper powder in order to reduce wear between the aluminum rotor and the friction lining.

[0005] DE 69513634 T2 describes a friction lining mixture for the same sector, which must contain 5-80% by volume of finely dispersed aluminium oxide with a special particle size.

[0006] WO 94 / 15112 relates to a brake lining for disc brakes having aluminium brake discs, the composition of which is said to be determined so that the friction value remains constant at a high value up to a temperature of 400°C and decreases significantly in the range up to 450°C.

[0007] Aluminum-containing friction linings are also known in the prior art.

[0008] WO2015 / 193361A1 describes a copper-free friction material containing 5-9.75% fibers of an Al-Mg alloy, such as AlMg5.

[0009] DE 19828301 A1 relates to friction linings which contain 0.5 to 15% by weight of an Al-Zn alloy, for example AlZn5, and therefore have anticorrosive properties.

[0010] KR1020010091694 describes a friction lining which may contain more than 90% by mass of Al metal (powder) and / or Al alloys.

[0011] Finally, CN104265816 describes a friction lining with 20-30 mass% Al alloy and silicon carbide (SiC), where the Al alloy is used as a replacement for steel fibers in the friction lining mixture, resulting in improved friction, wear and temperature properties. [Prior art documents] [Patent documents]

[0012] [Patent Document 1] DE69403791T2 [Patent Document 2] DE69513634T2 [Patent Document 3] WO94 / 15112 [Patent Document 4] WO2015 / 193361A1 [Patent Document 5] DE19828301A1 [Patent Document 6] KR1020010091694 [Patent Document 7] CN104265816 Summary of the Invention [Problem to be solved by the invention]

[0013] In summary, it can be seen that copper-containing friction linings are generally proposed in the prior art for use in combination with aluminum brake discs or rotors. However, copper is classified by various environmental authorities as a heavy metal and therefore as not environmentally compatible, so that a trend towards copper-free brake or friction linings can be seen. However, copper-free friction linings show very low friction values ​​against aluminum discs, usually around 0.3.

[0014] The above Al-containing friction linings are described for use in combination with conventional brake discs (cast iron, steel), the use of aluminum or aluminum alloys being intended to provide, for example, a replacement for steel fibers in such linings or to improve the anticorrosive properties of said linings.

[0015] Finally, it is generally known in the art that friction linings used for use with cast iron rotors cannot be used on the aluminum base layer of the rotor because the wear material of such friction linings will damage the aluminum base layer of the rotor, so that ultimately a stable friction coefficient is not achieved.

[0016] The object of the present invention is therefore to provide friction linings or friction lining formulations (or compositions) which ensure (guarantee) sufficiently high friction values ​​in combination with Al-containing brake discs or rotors and at the same time do not have or only have to a significantly reduced extent the disadvantages of prior art friction linings with regard to wear, abrasion and temperature properties. [Means for solving the problem]

[0017] According to a first aspect of the invention, an aluminium-containing brake disc or Aluminum-containing Rotor and the brake disc or the rotor. For and a friction lining, The friction lining comprises: Contains more than 5% by mass of aluminum in the form of an aluminum alloy thing , The aluminum alloy has the formula Al x Z y where Z is Mg and / or Ti, and x and y each represent a range of 10% by mass to 90% by mass. Characterized by: Brake system is provided (form 1) 。 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] A preferred embodiment of the invention is now presented. (Mode 1) See the first aspect of the present invention above. (Form 2) Form 1 Brake system In the above, the friction lining preferably contains 5 to 30 mass % of aluminum, or 5 to 25 mass % of aluminum, or 10 to 20 mass % of aluminum. (Form 3) Form 1 or 2 Brake system In the above, the aluminum alloy preferably contains, as Z, in addition to Mg and / or Ti, one or more of the following metals: Si, Ba, Sr, Ca, Be, Zr, Cr, Fe, Sn, and Bi. (Form 4) Form 1 or 2 Brake systemIn the above, the Al alloy is preferably a binary Al-Mg alloy or an Al-Ti alloy. (Form 5) Form 3 Brake system In the above, the Al alloy is preferably a ternary or quaternary alloy containing Mg and / or Ti and in which y is the sum of the proportions of a plurality of components Z. (Form 6) Form 4 Brake system In the above, the Al alloy is preferably AlTi10 or AlMg50. (Form 7) Any of forms 1 to 6 Brake system In the above, the Al alloy is preferably present and used in the form of particles. (Form 8) Form 7 Brake system In the above, the particles preferably have a particle size of 100 to 700 μm. (Form 9) Any of forms 1 to 8 Brake system In the brake disc or The above The rotor preferably contains 20 to 60% by volume, or up to 40% by volume, of aluminum. 。

[0019] In the sense of the present invention, the term aluminum-containing brake disc or rotor is generally understood as a brake disc or rotor which contains or consists of aluminum in the form of metal or in the form of an aluminum alloy. What are considered to be newer materials for brake discs and rotors are the so-called aluminum-metal matrix composites (Al-MMC), which are a type of aluminum alloy with particulate or fibrous reinforcements. These reinforcements / components significantly increase the strength and hardness of aluminum-based alloys. In this case, SiC (10-90% by volume) is preferably used as the reinforcing material, but aluminum oxide and other ceramic materials can be used as well.

[0020] The concentration of aluminium in prior art brake discs, which can also be used in the present invention, is typically between 20 and 60% by volume (calculated as metallic aluminium), in particular around 40% by volume.

[0021] The object of the present invention is achieved by using aluminum and / or its so-called compounds, in particular aluminum alloys, in the manufacture of friction linings. In this case, aluminum as metal (e.g. as unalloyed metal powder) is preferably used as a friction lining component. In the case of aluminum alloys, slightly alloyed Al alloys are preferred. In this case, wear-resistant Al alloys can have a positive effect on the friction behavior of friction linings constructed in this way. This applies in particular to alloys with improved temperature stability.

[0022] In this case, an aluminum concentration of at least 5% to 30% by weight is preferred, but higher aluminum concentrations are also possible. The weight percent designation here relates to the proportion of aluminum (expressed as metal, Al alloys converted accordingly to the Al content) in the finished friction lining mixture, from which the friction lining is subsequently produced according to the usual methods known in the prior art. The preferred concentration of aluminum in the friction lining is 5-25% by weight, in particular 10-20% by weight.

[0023] Preferred friction linings according to the invention contain metallic aluminum (unalloyed), especially in the form of a powder, and / or in the form of aluminum alloy(s).

[0024] It has been found (by the present invention) that Al alloys with magnesium (Mg) or titanium (Ti) are particularly suitable for solving the object of the present invention. Other alloying partners, such as silicon (Si), are also suitable in principle. This can be a binary, ternary or quaternary alloy system, of which binary aluminum alloys are particularly preferred. Al x Zy It has been found (by the present invention) that these binary systems of the type (Z is preferably Mg or Ti, x=10-90% by weight and y=10-90% by weight) are particularly preferred. Here, mention may be made, inter alia, of alloys such as AlTi10 and AlMg50.

[0025] The alloy according to the invention contains one or more of the following metals: Mg, Ti, Si, Ba, Sr, Ca, Be, Zr, Cr, Fe, Sn, Bi, but always aluminum. The friction lining mixture according to the invention can also contain a powder of a metal mixture containing the above mentioned components. The production of the alloy is carried out by melting and homogenizing the components into a finely dispersed system. Many such alloys are available on the market.

[0026] The proportion of the alloys according to the invention in the friction lining mixture or in the finished friction lining can preferably be 5-30% by weight, in particular 10-20% by weight. These alloys can be used in all existing friction linings. A special adaptation of the other components of the friction lining to the alloys described here is therefore not essential. In prior art mixtures, for example, only the Zn or Zn alloy components are preferably replaced by the alloys according to the invention. The mass proportion of the Al alloys in the friction lining mixture depends on the desired Al content, taking into account any additionally present Al metal (powder).

[0027] The alloy according to the invention is preferably introduced into the friction lining mixture in the form of a powder or in the form of particles. It is also possible to contain tin sulfide as lubricant in a mass proportion of approximately 0.5 to 10 mass %, preferably approximately 2 to 8 mass %.

[0028] For the production of friction linings, the aluminum alloy, preferably present in the form of strands (pellets) or blocks, is first liquefied (melted) and then sprayed (atomized) through a nozzle to produce substantially spherical particles, which are then mixed with a conventional friction material mixture or with the components of a conventional friction lining mixture and pressed at known temperatures and pressures to produce the friction linings.

[0029] However, it is also possible to form powdery particles directly from the alloy melt, for example by jetting from a nozzle or by centrifugal radiation spraying through the edge of a rotating disk. The particle size of the alloy according to the invention is preferably in the range of 100 μm to 700 μm. Aluminum alloys in the form of particles with further metals, for example Al / Mg alloys, are also available on the market.

[0030] As fillers for the friction lining according to the invention, metal oxides, metal silicates and / or metal sulfates can be included, either alone or in combination with other fillers. The fibrous material is preferably composed of aramid fibers and / or other organic or inorganic fibers. As metals, besides aluminum alloys, it is also possible to include, for example, steel wool and / or copper wool.

[0031] As lubricant, preferably tin sulfide is used in a mass proportion of 0.5 to 10% by weight, preferably 2 to 8% by weight, which can be added to the friction lining mixture, for example as a powder.

[0032] The alloy according to the invention can be used in principle in any friction lining mixture. The production of the friction lining according to the invention can be carried out according to traditional and known methods from the prior art, in particular by mixing all the starting components and pressing the friction lining mixture thus obtained at increased pressure and increased temperature. In this case, the Al alloy is fed as a powder together with the other mixture components to a mixer in a typical application and is thus homogeneously distributed in the friction material during the mixing process of the alloy particles. This further means that during the friction process when the corresponding brake lining is used, new Al-containing material always appears on the surface of the friction lining. Thus, during the use cycle of the friction lining, uniform or constant conditions always prevail on its surface.

[0033] By using the friction lining according to the invention, in combination with an Al-containing brake disc or rotor, sufficiently high friction values, for example 0.35 to 0.4, can be achieved while at the same time reducing wear at the brake disc / rotor. EXAMPLES

[0034] The friction material mixture according to the invention can have, for example, the following composition: Raw material mass% Aluminum-Mg / Ti alloy 10~20 (>5% Al by mass) Aluminum oxide 0.5~2 Mica powder 5~8 Barite 5~30 Iron oxide 5~15 Tin sulfide 2~8 Graphite 2~6 Coke powder 10~20 Aramid fiber 1~25 Resin filler powder 2~6 Adhesive resin 3~7

[0035] Furthermore, the mixture according to the invention can contain, in addition to aluminum (as metal or in the form of an alloy), for example also steel / steel wool, copper and / or copper alloys.

[0036] The present invention therefore relates to the use of Al alloys and Al metals according to the invention for friction linings to be used in combination with aluminium-containing brake discs and rotors.Furthermore, the present invention relates to the use of brake linings according to the invention for the above-mentioned purposes and to braking systems comprising friction or brake linings according to the invention and said brake discs or rotors.

[0037] Hereinafter, possible configurations of the invention will be described. [Appendix 1] Use of a friction lining containing more than 5% by mass of aluminum in the form of aluminum metal or in the form of an aluminum alloy as a friction lining for an aluminum-containing brake disc or rotor. [Appendix 2] In the above-mentioned use, the friction lining contains 5 to 30 mass % of aluminum, particularly preferably 5 to 25 mass % of aluminum, and particularly preferably 10 to 20 mass % of aluminum. [Appendix 3] In the above use, the aluminum alloy contains, in addition to Al, one or more of the following metals: Mg, Ti, Si, Ba, Sr, Ca, Be, Zr, Cr, Fe, Sn, and Bi. [Appendix 4] As a component of a friction lining for an aluminum-containing brake disc or rotor, x Z y The above-mentioned use of an Al alloy, wherein Z is Mg and / or Ti and / or Si, and x and y each represent a range of 10 mass % to 90 mass %. [Appendix 5] In the above use, the Al alloy is a binary Al-Mg alloy or an Al-Ti alloy. [Appendix 6] In the above use, the Al alloy is a ternary or quaternary alloy containing Mg and / or Ti and / or Si, and y is the sum of the proportions of multiple components Z. [Appendix 7] In the above use, the binary Al alloy is AlTi10 or AlMg50. [Appendix 8] In the above uses, the Al alloy is present and used in the form of particles. [Appendix 9] In the above use, the particles have a size (particle size) of 100 to 700 μm. [Appendix 10] In the above use, the brake disc or rotor contains aluminum in an amount of 20 to 60% by volume, in particular up to about 40% by volume. [Appendix 11] A brake system including the above friction lining and brake disc. [Appendix 12] Friction linings for aluminium-containing brake discs or rotors, containing more than 5% by mass of aluminium in the form of aluminium metal or in the form of an aluminium alloy. [Appendix 13] In the above friction lining, the friction lining contains 5 to 30 mass % of aluminum, or 5 to 25 mass % of aluminum, or 10 to 20 mass % of aluminum. [Appendix 14] In the above friction lining, the aluminum alloy contains, in addition to Al, one or more of the following metals: Mg, Ti, Si, Ba, Sr, Ca, Be, Zr, Cr, Fe, Sn, and Bi. [Appendix 15] In the above friction lining, the Al alloy is represented by the formula Al x Z y where Z is Mg and / or Ti and / or Si, and x and y each represent a range of 10 mass % to 90 mass %. [Appendix 16] In the above friction lining, the Al alloy is a binary Al-Mg alloy or an Al-Ti alloy. [Appendix 17] In the above friction lining, the Al alloy is a ternary or quaternary alloy containing Mg and / or Ti and / or Si, and y is the sum of the proportions of a plurality of components Z. [Appendix 18] In the above friction lining, the binary Al alloy is AlTi10 or AlMg50. [Appendix 19] In the above friction lining, the Al alloy is present and used in the form of particles. [Appendix 20] In the above friction lining, the particles have a particle size of 100 to 700 μm. [Appendix 21] In the above friction lining, the brake disc or rotor contains aluminum in an amount of 20 to 60% by volume, or up to 40% by volume. [Appendix 22] A brake disc including the above friction lining. [Appendix 23] A brake system including the above brake disc.

Claims

1. 1. A braking system comprising an aluminium-containing brake disc or an aluminium-containing rotor and a friction lining for said brake disc or rotor, comprising the friction lining contains more than 5% by weight of aluminum in the form of an aluminum alloy; The aluminum alloy has the formula Al ｘ Z ｙ where Z is Mg and / or Ti, and x and y each represent a range of 10% by mass to 90% by mass. A brake system characterized by:

2. 2. The brake system of claim 1, The friction lining contains 5 to 30% by mass of aluminum, or 5 to 25% by mass of aluminum, or 10 to 20% by mass of aluminum. A brake system characterized by

3. 3. The brake system according to claim 1, The aluminum alloy contains, in addition to Mg and / or Ti as Z, one or more of the following metals: Si, Ba, Sr, Ca, Be, Zr, Cr, Fe, Sn, and Bi. A brake system characterized by

4. 3. The brake system according to claim 1, The aluminum alloy is a binary Al-Mg alloy or an Al-Ti alloy. A brake system characterized by

5. 4. The brake system according to claim 3, The aluminum alloy is a ternary or quaternary alloy containing Mg and / or Ti, and y is the sum of the proportions of a plurality of components Z. A brake system characterized by

6. 5. The brake system according to claim 4, The aluminum alloy is AlTi10 or AlMg50. A brake system characterized by

7. In the brake system according to any one of claims 1 to 6, The aluminum alloy is present and used in particulate form. A brake system characterized by

8. 8. The brake system according to claim 7, The particles have a particle size of 100 to 700 μm. A brake system characterized by

9. In the brake system according to any one of claims 1 to 8, The brake disc or rotor contains 20 to 60% by volume, or up to 40% by volume, of aluminum. A brake system characterized by