Vehicle brake components and their manufacturing methods

Abstract

This invention relates to a component of an automotive brake system having a metal substrate with surfaces (5a, 5b) to which a coating (B) is provided for increased wear resistance. The coating comprises an intermediate layer (Z) on the substrate (2) and a cover layer (D) on the intermediate layer (Z), the cover layer being composed of a stainless steel matrix (E) and hard material particles (HP) embedded therein. To further optimize the performance of this component, the invention specifies that the average particle diameter of the hard material particles (HP) in the stainless steel matrix (E) embedded in the cover layer (D) is 10 μm to 125 μm, and that each hard material particle (HP) has an unmelted core region (K) composed of unaffected material of the hard material particles (HP), which is at least segmentally surrounded by a mixing region (M) formed by the material of the stainless steel matrix (E) and the corresponding hard material particles (HP), through which the hard material particles (HP) are respectively bonded to the stainless steel matrix (E) material. The invention also provides a method for producing such a coated component.

Description

Technical Field

[0001] The present invention relates to a component of a vehicle brake having a metal substrate having a surface having a coating to increase its wear resistance, the coating comprising an intermediate layer on the substrate and a cover layer on the intermediate layer, the cover layer being composed of a stainless steel matrix and hard material particles embedded therein.

[0002] Similarly, the present invention relates to a method for producing a component for a vehicle brake, wherein an intermediate layer is formed on the substrate surface of the component, and a cover layer formed of a stainless steel matrix and hard material particles embedded therein is subsequently formed on the intermediate layer by a further laser cladding welding process, wherein in the laser cladding welding process, a laser beam moves across stainless steel powder applied to the free surface of the intermediate layer. Background Technology

[0003] A component of this type, designed as an internally ventilated brake disc, is known in DE 10 2008 053 ​​637 B4. In this brake disc, the friction surface formed on the friction ring of the brake disc, upon which the brake pads press during braking, is covered with a double-layer coating. The intermediate layer is applied directly to the friction surface of the brake disc substrate and serves to bind the outer coating layer located thereon and to dissipate heat energy introduced into the outer layer during braking. The intermediate layer is composed of a zinc-based and / or nickel-based alloy, while the outer coating layer is a carbide layer or a metal matrix composite layer. The thickness of the coating is adapted to the geometry of the internally ventilated disc by making the coating thickness above the cooling channels of the brake disc greater than the thickness above the noppen or plate that separates the cooling channels.

[0004] DE 10 2005 008 569 A1 also describes a brake disc with a two-layer coating applied to its friction surface. These coatings are produced by coating powder. The coating powder is composed of a nickel- or nickel-cobalt-based matrix, into which hard material particles, such as WC or TiO2, are added to adjust the required hardness. The coating powder is applied to the surface of the brake disc to be coated by high-speed flame spraying, where a thin intermediate layer is first sprayed, followed by a thicker topcoat layer. A heat treatment is then performed, in which the previously sprayed coating is melted to create a material bond with the brake disc substrate made of gray cast iron. Here, the toughness and hardness of each layer are coordinated, ensuring adhesion of the topcoat layer through the intermediate layer.

[0005] As can also be seen from US 5,407,035 A, the coating on the friction surface of the brake disc is formed in at least two layers, such that the bonding of the overlay layer thereon is achieved through an intermediate layer located on the brake disc substrate, wherein the thickness of the intermediate layer is significantly less than the thickness of the overlay layer.

[0006] A component and method of the type shown in the opening are known from WO 2020 / 043712 A1. In this case, the component known in this disclosure includes a metal substrate having a surface with a coating to increase its wear resistance. The coating includes an intermediate layer on the substrate and a cover layer on the intermediate layer, wherein the intermediate layer has higher toughness than the cover layer, and the cover layer has higher hardness than the intermediate layer. To simplify the manufacture of such a component and improve its wear resistance, the intermediate layer is composed of a nickel alloy or a chromium alloy, with a nickel or chromium content exceeding 50% by weight, and hard material particles may be selectively added to the intermediate layer to improve wear resistance. On the other hand, the cover layer is formed from a stainless steel matrix with hard material particles embedded therein, wherein the thermal conductivity of the substrate is 1.5 to 3 times greater than that of the intermediate layer, and the thermal conductivity of the cover layer is 2 to 4.5 times greater than that of the substrate, wherein the thickness ratio Vd = Dd / Dz formed by the thickness Dz of the intermediate layer and the thickness Dd of the cover layer applies: Vd ≥ 1.5.

[0007] For the application of a capping layer, WO 2020 / 043712A1 specifies a high-speed laser cladding welding method as described in DE102011100456B4. In this method, a molten pool containing at least one molten filler material is formed on the surface to be coated by irradiating the molten pool with a laser beam. This is achieved by melting the filler powder through the laser beam, wherein the filler material is melted by the laser beam at a certain distance from the molten pool and fed into the molten pool in a completely molten form. During this process, the molten pool and the focal point of the laser beam move parallel to each other at a speed of at least 20 m / min relative to the surface to be coated, and the powder density is adjusted so that the laser power of the laser beam in the molten pool is less than 60% of the laser power before the laser beam contacts the powder. By using such a method, a particularly dense adhesion between the intermediate layer and the capping layer can be achieved, thereby minimizing the risk of delamination between the capping layer and the intermediate layer or the entire coating and the substrate to a certain extent. The decisive advantage of the method known from DE 10 2011 100 456 B4 is that the filler material is fed into the molten pool in an aggregated state, and the molten pool is aggregated on the surface of the part. This eliminates the time required to melt the powder particles in the molten pool. This, in turn, reduces the time required for layer formation, thereby allowing for a significant increase in processing speed. Summary of the Invention

[0008] The objective is proposed within the context of existing technology, namely, to realize a braking component of the type mentioned at the beginning and explained in detail above, which has further optimized usage characteristics compared with existing technology.

[0009] In addition, a method should be specified that enables the reliable manufacture of such components.

[0010] This invention achieves this objective through a component of a vehicle brake.

[0011] The method for producing such a component according to the present invention is given below.

[0012] Advantageous designs of the present invention are explained in detail below together with the general concept of the invention.

[0013] Accordingly, the component of the vehicle brake according to the invention includes a metal substrate having a surface having a coating to increase its wear resistance, the coating including an intermediate layer on the substrate and a cover layer on the intermediate layer, the cover layer being composed of a stainless steel matrix and hard material particles embedded therein.

[0014] According to the present invention, the average particle diameter of the hard material particles in the stainless steel matrix embedded in the cover layer is 10 μm to 125 μm, wherein the hard material particles have an unmelted core region composed of unaffected material of the hard material particles, which is at least segmentally surrounded by a mixing region formed by the material of the stainless steel matrix and the material of the corresponding hard material particles, the hard material particles being respectively bonded to the stainless steel matrix material through the mixing region.

[0015] In the method for producing vehicle brake components according to the present invention, an intermediate layer is manufactured on the surface of the component's substrate in a first step, and a cover layer consisting of a stainless steel matrix and embedded hard material particles is formed on the intermediate layer by a laser cladding welding process in a second step. In the laser cladding welding process, a laser beam moves across stainless steel powder applied to the free surface of the intermediate layer. Here, during the manufacture of the cover layer, the laser intensity is 0.1-2.5 kW / mm². 2 The laser beam is directed at the stainless steel powder applied to the intermediate layer. Simultaneously, the laser beam is configured such that the diameter of the spot on which the laser beam strikes the applied stainless steel powder and melts the powder into a molten pool is 2.5-15 mm. Finally, according to the invention, hard material particles with an average particle diameter of 15 μm to 125 μm are added to the molten pool formed in this manner.

[0016] This invention is based on the understanding that hard material particles in a stainless steel matrix of a coating layer have a core region that bonds with the stainless steel matrix through a surrounding mixing zone, thereby ensuring optimal retention of the hard material particles within the stainless steel matrix. Simultaneously, according to the invention, the hard material particles present in the stainless steel matrix can optimally support the hardness of the coating layer because their core region retains its original hardness before the introduction of the coating layer. Therefore, the coating layer in which the hard material particles are fixed in a material-fit manner according to the invention makes the best contribution to the wear resistance and effectiveness of brake components coated with the coating system according to the invention.

[0017] Therefore, in the capping layer according to the invention, there is an intermediate layer between the hard material particles and the surrounding stainless steel matrix material, the composition of which differs from both the composition of the hard material particles and the composition of the stainless steel matrix. This mixed layer, composed of a mixture of stainless steel matrix and hard material particles, and typically surrounding the core of the hard material particles, is formed when the hard material particles are partially melted during laser beam processing for the production of the capping layer, thereby allowing the molten material of the stainless steel matrix and the molten material of each respective hard material particle to flow into each other, thus forming the mixed layer. According to the invention, on the one hand, by embedding only sufficiently large particles in the stainless steel matrix of the capping layer, and on the other hand, by limiting the laser energy density required for the hard material particles to embed in the stainless steel matrix according to the method of the invention, the formation of the mixed layer is facilitated, while reliably preventing the complete melting of the hard material particles.

[0018] Therefore, the hard material particles embedded in the coating layer according to the present invention do not completely melt but are retained in their core region, which maximizes robustness and thus maximizes the effectiveness of the coating formed according to the present invention.

[0019] Accordingly, according to the present invention, the parameters of the laser cladding welding process used for producing the capping layer are selected such that the localized heat input by the laser beam into the stainless steel powder applied to the intermediate layer for forming the capping layer is sufficient to melt the powder in the region of the laser spot, i.e., the region hit by the laser beam. However, this is simultaneously limited in such a way that the melting of the hard material particles introduced into the molten pool formed in the laser spot is restricted to the peripheral region of the hard material particles. In this way, a dense material bond of the hard material particles is established through the mixing zone formed by the melting peripheral region of the hard material particles and the adjacent molten stainless steel matrix, while the core region of the hard material particles remains in the state when the hard material particles are introduced into the molten pool.

[0020] Simultaneously, the laser intensity and the diameter of the laser spot striking the stainless steel powder are coordinated to ensure that the melt formed therein remains molten for as long as possible, despite the supply of hard material particles. Therefore, the hard material particles introduced into the molten pool have sufficient time to distribute uniformly within the molten pool before solidification.

[0021] Therefore, the component with the coating according to the invention is characterized in that hard material particles are located in the coating layer in a uniformly distributed manner. This, in turn, contributes to the uniform distribution of high wear resistance on the surface covered by the coating layer in the component according to the invention.

[0022] If the maximum laser intensity of the laser beam used to generate the capping layer is 1.2 KW / mm 2Therefore, optimized manufacturing results can be achieved in the method according to the present invention.

[0023] In this case, considering the size of the laser spot falling on the stainless steel powder forming the coating matrix according to the present invention, the laser power of the laser beam used to produce the coating layer is 6-25KW, which can achieve the laser intensity specified according to the present invention.

[0024] Another modifiable variable that can influence the laser intensity, and thus the localized heat input in the spot region where the laser beam falls on the powder forming the stainless steel matrix, is the diameter of the laser spot. According to the invention, this diameter is 2.5-15 mm, with a diameter of at least 8 mm proving particularly suitable in practical tests, while a spot diameter of up to 12.5 mm can achieve optimal processing results.

[0025] The thickness of the coating applied according to the invention after polishing is typically 50-200 μm, especially 50-150 μm, with a coating thickness of 80-140 μm proving particularly advantageous in practical tests. On the other hand, the thickness of the coating in the unpolished state is typically 50-300 μm.

[0026] In principle, the intermediate layer provided according to the invention can be applied to the respective surfaces of the component to be coated by any thermal application process, such as cladding welding, spray welding, or plasma welding. The techniques required in this regard are largely known from the prior art. For example, the high-speed laser cladding welding method mentioned in DE 10 2011100 456B4 above is suitable for this purpose.

[0027] The intermediate layer can be made of steel already used for this purpose in existing technologies, especially stainless steel, which has sufficient toughness. An example of such stainless steel is 316L steel standardized according to the American AISI / ASTM standards.

[0028] The intermediate layer provided in the coating according to the invention achieves several functions. On the one hand, it compensates for unevenness and depressions, such as holes or cracks, present on the surfaces of the respective components covered by the coating. On the other hand, the intermediate layer absorbs and compensates for stress caused by temperature.

[0029] To meet these requirements, the intermediate layer can have a thickness of 50-200 μm, especially 50-150 μm, with an intermediate layer thickness of 80-140 μm proving particularly advantageous in actual tests.

[0030] According to the invention, the matrix of the coating is formed of stainless steel. These stainless steels particularly include austenitic stainless steels. For example, stainless steel suitable for this purpose is standardized as material number 1.4404, or as number series 316-431L according to American standards AISI / ASTM. Steels with reduced or ineffective nickel content are particularly preferred.

[0031] The hard material particles embedded in the capping matrix ensure the required hardness and the associated wear resistance of the capping layer. Suitable hard material particles for this purpose are, in particular, metallic, covalent, or ionic carbides. According to the invention, the hard materials present in the capping layer and selectively located in the intermediate layer particularly include tungsten carbide, chromium carbide, titanium carbide, vanadium carbide, or silicon carbide. When the volume percentage of hard material particles embedded in the capping steel matrix accounts for 20-70% of the total volume of the capping layer, an optimal ratio of matrix material to hard material particles is achieved in terms of the performance characteristics of the capping layer. Higher hard material content degrades the strength and heat transfer properties of the capping layer. At lower hard material content, the required hardness cannot be achieved.

[0032] When introduced into the capping layer, the hard material particles embedded in the stainless steel matrix of the capping layer according to the present invention have an average particle size of 15-135 μm. In the embedded state, the hard material particles remain unchanged, and the unmelted core region still has a diameter of 15-125 μm. In practical tests, it has proven particularly useful if the average particle diameter of the hard material particles embedded in the stainless steel matrix of the capping layer is at most 105 μm. According to the present invention, hard material particles with a wide range of particle size profiles can therefore be processed. This makes the production of the capping layer according to the present invention particularly cost-effective. For more stringent requirements, the particle size of the hard material particles can be more strictly screened. For example, it is advantageous to add hard material particles with an average particle size of at least 20 μm, especially at least 35 μm or at least 45 μm, to the capping layer. Therefore, the average particle diameter of the hard material particles introduced into the coating layer according to the present invention is preferably 20-105 μm, more preferably 35-105 μm, 45-105 μm, or 20-60 μm, wherein particularly good results are expected when using hard material particles with an average particle size of 35-60 μm, especially 45-60 μm. Hard material particles of 20-60 μm, especially 35-60 μm or 45-60 μm are particularly suitable for applications where the laser spot diameter does not exceed 8 mm, while particle sizes of 35-105 μm, especially 45-105 μm, are suitable for processing with a spot diameter ≥ 8 mm.

[0033] Due to the embedding of hard material particles according to the invention, the coating layer according to the invention has a hardness of 700 HV10 to 1250 HV10 as determined according to DIN EN ISO 6507-1. Typically, the coating layer according to the invention has a hardness of 850-1050 HV10.

[0034] Here, since the hard material particles embedded in the cover layer are uniformly distributed according to the present invention, the component according to the present invention is characterized in that the difference between the minimum value Hmin of the surface hardness determined on the free surface of the cover layer and the maximum value Hmax of the surface hardness determined on the free surface of the cover layer is at most 250HV10, especially 100HV10 (i.e. [Hmax-Hmin]≤100HV10).

[0035] The present invention is particularly effective in the following cases: the component coated according to the invention is the friction ring of a brake disc, and the coated surface is a friction surface existing on the friction ring, which is acted upon by an actuating device with brake pads during braking. Here, the friction ring can be a separately manufactured component of the brake disc, connected to a corresponding support portion of the brake disc in a specific assembly step, as in the case of a so-called "assembled brake disc" or a brake disc where the support portion is cast onto the friction ring in a separate working step, or the friction ring is cast onto the support portion in a separate working step. Similarly, the friction ring can, of course, also be part of a brake disc integrally formed, particularly by casting technology, where the support portion and the friction ring are connected to each other as a single piece.

[0036] If the free surface of the coating applied according to the present invention is found to have excessive roughness or unevenness, the relevant surface can be ground to achieve sufficient smoothness and roughness. In the case where the surface of the coating according to the present invention is the friction surface of a brake disc, the target value is an average roughness Ra of 1-3.2 μm, particularly 1.4-1.7 μm, as determined according to DIN EN ISO 4288, and the smoothness deviation is at most 20 μm.

[0037] The material constituting the matrix of the component according to the invention is typically a metal casting material, which allows the matrix to be produced using casting techniques. This particularly includes iron or aluminum casting materials, which have particularly good thermal conductivity, meeting the requirements of the invention, and are especially suitable for the production of friction rings.

[0038] To maintain the molten pool formed by stainless steel powder on a stainless steel matrix within the laser spot for as long as possible, it can be advantageous to preheat the part to a preheating temperature of 100-700°C before the laser beam strikes it. This delays heat loss from the molten pool to the part substrate, thus slowing down the solidification of the substrate material of the coating layer.

[0039] For preheating, the component can be heated as a whole in a suitable oven. For larger components or components where only certain surface sections require coating, preheating can also be limited to the surface sections requiring coating. In this case, adjacent surface sections can be heated sequentially before coating. Induction heating is particularly suitable for this purpose. It has proven particularly practical if localized induction heating is performed separately before the laser spot, that is, if the component is sequentially and locally heated before the laser beam in sections where the stainless steel powder is subsequently melted by the laser beam.

[0040] Preheating temperatures of 250-350°C have proven particularly suitable for the purposes of this invention. Preheating also helps reduce stress between the capping layer and the intermediate layer, as well as between the intermediate layer and the substrate. Attached Figure Description

[0041] The invention will now be explained in more detail with reference to one or more embodiments. (See figures:)

[0042] Figure 1 A cross-sectional view of a motor vehicle brake disc along its axis of rotation XX is shown;

[0043] Figures 2-4 The image shows a grinding disc with a coating formed on the brake disc, transverse to the circumference of the brake disc. Detailed Implementation

[0044] The brake disc 1, which is a component in the sense of the present invention, has a base 2, which is designed in a conventional manner and cast from a cast iron material known for this purpose, with the DIN-EN designation EN-JL1040.

[0045] The brake disc 1 has a cup-shaped support portion 3 and a friction ring 4 cast on it, shown here as being made of solid material, but it can also be designed in a conventional way as an internally ventilated friction ring 4.

[0046] The friction ring 4 has annular friction surfaces 5a and 5b on its end face with the normal to the axis of rotation XX, respectively, in the same conventional manner.

[0047] In the substrate 2 prepared for coating, the friction surfaces 5a and 5b are prepared by cutting in a manner known per se after the substrate 2 is cast, so that they have an average roughness depth Rz of 20 μm on the upper side.

[0048] A coating B consisting of an intermediate layer Z and a cover layer D is applied to the friction surfaces 5a and 5b of the substrate 2, which are thus processed.

[0049] The intermediate layer Z is made of commercially available powdered stainless steel, such as the stainless steel material mentioned above, which is standardized as 316L. The thickness Dz of the intermediate layer Z is 120-140 μm.

[0050] To apply the intermediate layer Z, the brake disc is positioned horizontally in a clamping device (not shown here), which can be rotated about the rotation axis XX of the brake disc 1 by a rotary drive device (also not shown here). The intermediate layer Z is then produced by laser cladding welding. For this purpose, a laser beam device (laser head diameter = 5 mm, not shown here) is placed in a starting position at the inner diameter of the friction ring 4, and the brake disc 1 rotates at a speed of 60 revolutions per minute. Starting from the starting position, the laser moves radially along the outer circumference of the friction ring at a speed of 10 m / min. During startup, the laser is activated and deactivated when the outer diameter is reached. With the start of laser irradiation, powdered steel material for the intermediate layer Z is added to the area swept by the laser beam in the manner described in DE102011100456B4.

[0051] The intermediate layer Z compensates for the unevenness of the friction surfaces 5a and 5b and seals the hole 6. Therefore, after the intermediate layer Z is applied, there is a smooth surface on the side away from the substrate 2, which is best suited for applying the cover layer D.

[0052] In three tests, the covering layer D was applied as follows to three brake discs 1 that were each covered with the intermediate layer Z in the manner described above:

[0053] HP hard material particles, which are tungsten carbide particles, are provided.

[0054] The average particle diameter of the hard material particles HP is 25-60 μm.

[0055] A layer of powder is applied to a brake disc 1 that is rotatably clamped, similar to the application of an intermediate layer Z. The powder consists of stainless steel standardized as material number 1.4404 according to the Stahl Eisen-Liste.

[0056] The laser beam was directed onto the powder. In Experiments 1 and 2, the laser beam struck the powder layer sections located below it with a spot diameter of 2.9 mm. In Experiment 3, the laser beam struck the powder layer sections located below it with a spot diameter of 1.2 mm.

[0057] In Experiment 1, the laser intensity was 0.2 KW / mm. 2 In Experiment 2, the laser intensity was 2.20 KW / mm². 2 In Test 3, which is not based on the present invention, the laser intensity was 3.50 KW / mm. 2 .

[0058] By rotating the brake disc 1 around the rotation axis XX, the powder layer moves under the laser beam, so that the laser spot moves through the powder layer in sequence until the stainless steel powder is completely melted and solidified again after the corresponding number of rotations, thus forming the stainless steel matrix E of the covering layer D.

[0059] A certain amount of hard material particles HP is introduced into a molten pool formed of stainless steel powder in a laser beam spot. The amount is determined such that a steel melt exists in the molten pool, wherein the steel melt consists of up to 40% hard material particles HP and the remainder stainless steel melt.

[0060] The coating D manufactured in this way has a thickness Dd of 250 μm and a surface hardness of 950-1500 HV10.

[0061] A grinding disc oriented transversely to the circumferential direction is manufactured on the brake disc 1 coated in this manner. Figure 2 (Experiment 1) Figure 3 (Experiment 2) and Figure 4 As shown in (Experiment 3).

[0062] Figures 2-4 The diagram shows the cast iron material G of the brake disc 1, the intermediate layer Z on the cast iron material G, and the cover layer D on the intermediate layer Z, in which hard material particles HP are embedded.

[0063] The hard material particles HP each have a clearly identifiable internal core region K, which is not melted and is therefore in the state when the hard material particles HP are introduced into the molten pool generated by the stainless steel powder through a laser beam during the production of the capping layer D.

[0064] The core region K of the hard material particles HP is surrounded by a mixing zone M, in which the material of the hard material particles HP is mixed with the stainless steel material of the stainless steel matrix E of the covering layer D. Through the mixing zone M, the hard material particles HP are bonded to the stainless steel matrix E through their core region K.

[0065] It can be seen that, in the experiment conducted according to the present invention, i.e. with a laser intensity of 0.1 ≤ laser intensity ≤ 2.5, the core region K of the hard material particles HP exists in the stainless steel matrix E in a well-defined form.

[0066] Conversely, in Test 3, which did not meet the requirements of the present invention due to excessively high laser intensity, the hard material particles HP existed in a molten and severely deformed form, thus failing to conform to their original state as supplied, both in shape and performance. Figure 3 The area visible as black dots is entirely composed of a mixing zone, in which the fully molten hard phase material is mixed with the stainless steel material of the stainless steel matrix E.

[0067] Explanation of reference numerals in the attached figures

[0068] 1 brake disc

[0069] 2. Brake disc base 1

[0070] 3 Brake disc support part 1

[0071] 4. Friction ring of brake disc 1

[0072] Friction surfaces 4 of friction rings 5a and 5b

[0073] 6 holes

[0074] B coating

[0075] D coating layer B

[0076] Thickness of Dd capping layer D

[0077] Thickness of the intermediate layer Z in Dz

[0078] Stainless steel matrix of E-coating layer D

[0079] G brake disc 1 cast iron material

[0080] HP Hard Material Particles

[0081] The core area of ​​K hard material particles

[0082] The rotating shaft of X brake disc 1

[0083] Intermediate layer of Z coating B

[0084] M surrounds the hybrid layer of hard material particles HP

Claims

1. A component of a vehicle brake, the component having a metallic substrate having surfaces (5a, 5b) wherein a coating (B) is provided on the surfaces to increase their wear resistance, the coating comprising an intermediate layer (Z) on the substrate (2) and a cover layer (D) on the intermediate layer (Z), the cover layer being composed of a stainless steel matrix (E) and hard material particles (HP) embedded therein, characterized in that, The hard material particles (HP) embedded in the stainless steel matrix (E) of the cover layer (D) have an average particle diameter of 10 μm to 125 μm, and the hard material particles (HP) have an unmelted core region (K) composed of unaffected material of the hard material particles (HP), which is at least segmentally surrounded by a mixing region (M) formed by the material of the stainless steel matrix (E) and the material of the corresponding hard material particles (HP), the hard material particles (HP) being bonded to the stainless steel matrix (E) material through the mixing region respectively.

2. The component according to claim 1, characterized in that, The stainless steel matrix (E) of the covering layer (D) is formed of stainless steel with material number 1.4404, or stainless steel with number series 316-431L as standardized by American standard AISI / ASTM.

3. The component according to any one of the preceding claims, characterized in that, The cover layer (D) has a hardness of 850-1050 HV10.

4. The component according to claim 3, characterized in that, The difference between the minimum surface hardness Hmin and the maximum surface hardness Hmax determined on the free surface of the capping layer (D) is at most 100HV10.

5. A method for producing vehicle brake components, wherein in a first step, an intermediate layer (Z) is formed on the surface of a substrate (2) of a component (1), and in a second step, a cover layer (D) formed of a stainless steel matrix (E) and hard material particles (HP) embedded therein is produced on the intermediate layer (Z) by a laser cladding welding process, wherein in the laser cladding welding process, a laser beam moves across stainless steel powder applied to the free surface of the intermediate layer (Z), characterized in that, During the manufacturing process of the capping layer (D), the laser intensity is 0.1-2.5 KW / mm. 2 The laser beam is directed at the stainless steel powder applied to the intermediate layer (Z), so that the laser beam hits the applied stainless steel powder and the diameter of the spot in which the stainless steel powder melts into a molten pool is 2.5-15 mm, and the hard material particles (HP) with an average particle diameter of 15 μm to 135 μm are added to the molten pool formed in this way.

6. The method according to claim 5, characterized in that, The average particle diameter of the hard material particles (HP) in the stainless steel matrix (E) embedded in the cover layer (D) is up to 105 μm.

7. The method according to claim 6, characterized in that, The average particle diameter of the hard material particles (HP) in the stainless steel matrix (E) embedded in the cover layer (D) is up to 60 μm.

8. The method according to any one of claims 5 to 7, characterized in that, The hard material particles (HP) embedded in the stainless steel matrix (E) of the cover layer (D) have an average particle diameter of at least 20 μm.

9. The method according to claim 8, characterized in that, The hard material particles (HP) embedded in the stainless steel matrix (E) of the cover layer (D) have an average particle diameter of at least 45 μm.

10. The method according to claim 5, characterized in that, The maximum laser intensity of the laser beam used to generate the capping layer (D) is 1.2 kW / mm². 2 .

11. The method according to claim 5, characterized in that, The laser power of the laser beam used to produce the capping layer (D) is 6-25KW.

12. The method according to claim 5, characterized in that, Before the laser beam strikes, the component is preheated to a preheating temperature of 100-700°C.

13. The method according to claim 12, characterized in that, The entire component is preheated to the preheating temperature before the stainless steel powder is applied.

14. The method according to claim 12, characterized in that, The component is locally preheated to a preheating temperature in a section where the stainless steel powder is subsequently melted by a laser beam.

15. The method according to claim 14, characterized in that, The component is preheated before the laser beam.

16. The method according to any one of claims 12 to 15, characterized in that, Preheating is performed using induction heating.

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