CU-FE BASED HYBRID CERAMIC REINFORCED COMPOSITE BRAKE PAD PRODUCTION METHOD

Abstract

The invention relates to an innovative manufacturing method aimed at overcoming the limitations of braking performance encountered in high-speed conditions in rail systems and railway transportation. The present invention presents a method in which hybrid ceramic reinforcements (Al₂O₃+SiO₃, Al₂O₃+ZrO₃, or Al₂O₃+SiC) are used in combination within a Cu and Fe-based metal matrix, and friction stability at high temperatures is maintained by the addition of solid lubricants such as graphite and MoS₃. In this method, selected powder materials are prepared to high purity in specific ratios, homogenized in a three-dimensional mixing device, pre-densified by cold pressing, and sintered to ensure strong bond formation between the metal matrix and the reinforcement phases. In this way, the hybrid reinforcements increase surface hardness and wear resistance, while the solid lubricant phases limit fluctuations in the coefficient of friction at high temperatures to within ±6%.Thus, the invention both preserves structural integrity by preventing thermal fatigue cracks and provides safe, stable, and long-lasting braking performance under high speed and pressure.

Description

1 TARIFF PRODUCTION OF CU-FE BASED HYBRID CERAMIC REINFORCED COMPOSITE BRAKE PADS. METHOD Technical Area The invention is a Cu-Fe based 5-layer steel designed to improve braking performance in high-speed trains. Hybrid ceramic reinforcements (Al₂O₃+SiO₂, Al₂O₃+ZrO₂, Al₂O₃+SiC) and solids into a metal matrix. An improved version produced by powder metallurgy method with integrated lubricants (graphite, MoS₂). It covers the composite brake pad manufacturing method. The invention is particularly suitable for high-speed conditions in rail systems and rail transport. an innovative production method aimed at overcoming the limitations of brake performance encountered 10 This is related. Current brake pads generally consist of single reinforcement elements (e.g., only SiO₂). or simply Al₂O₃) is produced and stability in the coefficient of friction under high temperature. Failure to provide this can lead to increased wear rates and the formation of thermal fatigue cracks. Problems are encountered. Additionally, the non-homogeneous particle sizes and matrix-reinforcement issues... This leads to microcracks and irregular wear at the interfaces, reducing the lifespan of brake pads by 15%. It abbreviates. The present invention aims to solve these technical problems using Cu and Fe-based metals. hybrid ceramic reinforcements (Al₂O₃+SiO₂, Al₂O₃+ZrO₂ or Al₂O₃+SiC) within the matrix used in combination, also with the addition of solid lubricants such as graphite and MoS₂. It presents a method in which friction stability is maintained at high temperatures. The method Within this scope, powdered materials are prepared with high purity and mixed in a three-dimensional mixing device. It is homogenized, pre-densified by cold pressing, and then... Sintering ensures the formation of strong bonds between the metal matrix and the reinforcement phases. This In this way, hybrid additives increase surface hardness and wear resistance, while solid lubricant phases Fluctuations in the coefficient of friction at high temperatures are within the range of ±6%. It limits it. Thus, the invention both prevents thermal fatigue cracks and structural 25 It maintains its integrity and is safe, stable, and long-lasting even under high speed and pressure. It provides braking performance. Previous Technique Brake pads used in railway transportation, especially in high-speed trains, are both... These are critical components for both passenger safety and the long-term operational stability of the system. The current 30 In these techniques, brake pads are generally made of individual fibers embedded in a copper (Cu) or iron (Fe) based metal matrix. ceramic reinforcements (e.g., only Al₂O₃, only SiO₂ or only SiC) and solids They are produced using powder metallurgy methods with the addition of lubricants (mostly graphite). 2 In these methods, powdered materials are weighed and mixed in specific proportions, then cold-cooled. The material is compressed by pressing and then sintered at high temperature to obtain a composite structure. However, this production approach is not feasible under high-speed and high-temperature conditions. It does not fully meet the requirements of the brake pads that will be used. In high-speed trains, temperatures at the brake pad-disc contact surface reach 500 °C to 500 °C during braking. This can reach such a level that it causes sudden fluctuations and instability in the coefficient of friction. The single ceramic reinforcements used in current techniques are suitable for this temperature range. It fails to provide a homogeneous distribution and does not have a sufficiently strong bond at the matrix-reinforcement interface. It is unable to do so. As a result, the brake pads are subjected to high thermomechanical loads. Oxidation, microcrack formation, and surface deterioration are observed on its surface. Especially 10 the relationship between a matrix (Cu or Fe) with different coefficients of thermal expansion and reinforcing particles Incompatibility leads to rapid progression of thermal fatigue cracks and severely reduces brake pad life. This leads to a shortening of the length of the vehicle. Another significant technical problem is the irregularity in particle size distribution and mixing. This is due to inadequacies in the process. The non-homogeneous internal structure causes problems during braking. This creates localized wear zones on the brake pad surface, resulting in uneven braking force. This causes it to disperse. Especially at high speeds, these irregularities cause friction. This causes the coefficient to fluctuate over time, jeopardizing both passenger safety and... This also negatively affects the performance stability of the system. Furthermore, the high density... Although brake pads offer an advantage in terms of durability, the heat generated due to their high thermal conductivity is 20%. Rapid spreading on the brake pad surface can disrupt friction stability and cause sudden performance issues. This can lead to losses. In current literature and practices, brake pads with Cu or Fe matrix, graphite or MoS₂ additives are used. Performance limitations are clearly evident under high-speed conditions. Graphite alone Although it exhibits lubricating properties at high temperatures, its structural design is compromised during prolonged braking cycles. It is unable to maintain its integrity and causes a decrease in the coefficient of friction. Similarly In this way, when only single additives such as Al₂O₃ or SiO₂ are used, under high temperature Due to matrix-reinforcement mismatch and particle agglomerations, both stiffness and The desired level of wear resistance cannot be achieved. Particles during sintering. Insufficient diffusion between them also reduces bond strength, and the high 30 This leads to the peeling of surface layers under pressure. At this point, the innovation brought by the current invention targets these technical shortcomings. The solution is to produce hybrid ceramic reinforcements (Al₂O₃+SiO₂, in a Cu-Fe based matrix. The combined use of Al₂O₃+ZrO₂ or Al₂O₃+SiC eliminates the limitations of single supplements. 3 by removing excess water, it provides both hardness, wear resistance, and thermal stability at high temperatures. Hybrid reinforcements provide advantages thanks to their different particle morphologies and mechanical properties. increasing load-carrying capacity, balancing thermal expansion differences, and It prevents the formation of microcracks. Furthermore, graphite and MoS₂ act as a lubricating phase together. Its use ensures that the friction coefficient remains stable within the ±6% range at high temperatures. This ensures safety during sudden braking. In the production method, a three-dimensional mixing device is used to ensure a homogeneous distribution of particles. The agglomeration and uneven wear problems seen in the previous technique have been eliminated. is removed. The cold pressing process, carried out at a pressure of 600 MPa, removes particles from between the parts. Increasing mechanical locking increases density; preferably in an argon atmosphere 10 Sintering at 900 °C creates a strong metal-ceramic bond between the metal matrix and the reinforcement phases. This process involves particles forming bonds under high pressure and temperature. by maximizing diffusion, it enhances matrix integrity and the hybrid composite structure. This ensures that it remains stable under high speed and high temperature conditions. Friction fluctuations, excessive wear rates, thermal fatigue cracks in current technology, 15 Problems such as inadequate particle distribution and reduced friction coefficient are common in Cu-Fe based products. This is largely surpassed by the hybrid ceramic-reinforced composite brake pad production method. This method is applicable not only in laboratory conditions but also in real high-speed trains. to offer safe, stable and long-lasting braking performance in its operations It is an innovative solution designed to fill the most critical gaps in existing technologies. It is of that nature. Patent document CA2796092C describes a hybrid ceramic composite brake pad. The invention is described as consisting of a semi-metallic section attached to a substrate and a section adjacent to this section, which is also... It describes a hybrid structure consisting of two separate ceramic composite sections bonded to a substrate. The ceramic composite acts as a semi-metallic section between the sections, while the wear indicator is 25. A substrate containing [specific material] emits an audible sound upon brake disc contact, allowing for the detection of wear level. It offers a component that provides both ceramic and semi-metallic materials in its structure. By combining these advantages, it optimizes brake pad performance and wear monitoring. Patent document number CN103195844B describes a material with high toughness and wear resistance. A new ceramic brake pad is being discussed. The invention involves red copper fiber, cellulosic fiber, 30 containing components such as aramid and mineral fibers, adhesive resin, and artificial graphite in specific proportions. It offers a composite material formulation. This provides both thermal stability and braking performance. Improved performance, along with reduced noise and vibration, resulting in quieter and more stable braking. is provided. 4 Patent document number RU2645857C1 describes the production of a metal-ceramic brake pad. The method is described. The invention involves a matrix based on iron containing copper, carbon, alumina, chromium, Seamless, segmented metals are produced by sintering components such as molybdenum and phosphorus via powder metallurgy. This envisages the creation of a brake block; however, this segmented structure makes the product mechanical. It shows deficiencies in terms of strength and wear resistance. 5 Patent document CN114321239A describes a ceramic fiber reinforced resin-based brake. The invention refers to a brake pad mixture material. It concerns braking on the brake disc surface. To reduce the hydrogen embrittlement effect that occurs during the process, binder hydrogen is used. Multi-fiber reinforced containing adsorbent component and diffusion-preventing transfer film component. It is based on a mixture. This mixture forms a nanoscale transfer layer, preventing disc cracking. It prevents and also reduces disc wear, providing energy-efficient and environmentally friendly braking. It is designed to deliver performance. Patent document number US5325941 describes a composite brake rotor and brake pads. The combination is mentioned. The invention involves a light metal such as aluminum or magnesium. It describes a composite rotor containing refractory ceramic particles sintered into a matrix and 15 Brake pads that match this composite rotor; copper oxide, antimony sulfide, silica alumina alloy, It works in combination with materials such as barium sulfate, Kevlar, zinc sulfide, coke, and graphite. This structure, It improves braking efficiency by increasing the structural strength and heat dissipation of the rotor. Investigations have revealed that the brake pads currently used in high-speed trains are generally of poor quality. with copper or iron-based matrices, singular solid lubricants such as graphite or MoS₂, and Al₂O₃, 20 By combining individual reinforcing elements such as SiO₂ or SiC using powder metallurgy methods. They were produced, but these structures showed significant limitations under high speed and temperature conditions. It is observed that surface temperatures can reach up to 500 °C during braking. This leads to sudden fluctuations in the coefficient of friction at the matrix-reinforcement interfaces. Microcracks and oxidation-related deterioration occur. Also, different 25 Incompatibility of materials with different coefficients of thermal expansion leads to rapid thermal fatigue cracking. This causes it to progress, and the irregularity in particle distribution results in localized erosion on the surface. By creating zones, it reduces braking stability. High-density matrices reduce durability. Although it provides performance, excessive thermal conductivity causes performance losses due to local temperature increases. These technical shortcomings result in friction stability and wear reduction in existing solutions. This limits resistance, shortens brake pad life, and increases safety risks. The present invention offers a solution to these problems: a hybrid ceramic within a Cu-Fe based metal matrix. combining the additives (Al₂O₃+SiO₂, Al₂O₃+ZrO₂ or Al₂O₃+SiC) with graphite It envisages the integration of MoS₂ as a simultaneous lubricant phase. This hybrid approach, By increasing thermal stability and surface hardness at high temperatures, it improves wear resistance to 35. strengthening, overcoming expansion mismatches through the synergistic effect of different ceramics It balances and reduces microcrack formation. Through three-dimensional mixing of powders. homogeneous distribution and 600 MPa cold pressing followed by preferably in an argon atmosphere. Sintering at 900 °C creates strong bonds between the matrix and the reinforcement phases. It maintains structural integrity by creating a friction coefficient of ±6.5%. By providing stability within its range, it offers reliable braking performance at high speeds. by reducing the wear rate and minimizing deterioration due to thermal fatigue, the existing It eliminates critical limitations in the techniques. Ultimately, the problems mentioned above, which cannot be solved with the current technology, are related to the technical aspects. This has made it necessary to make an innovation in the field. 10 Purposes and Brief Description of the Invention The main purpose of the invention is to reduce the high temperatures encountered during braking in high-speed trains. and a composite brake that is pressure-resistant, has a stable coefficient of friction, and high wear resistance. The aim is to present the brake pad production method. This allows for the application of a brake pad that withstands temperatures reaching 500°C during braking. Even at temperatures reaching up to 15 degrees, performance loss is minimized, ensuring safe, stable and long-lasting operation. Durable braking is provided. Another objective of the invention is to integrate hybrid ceramic reinforcements within a Cu-Fe based metal matrix. The aim is to enable their use in combination with (Al₂O₃+SiO₂, Al₂O₃+ZrO₂, Al₂O₃+SiC). Thus, both hardness and thermal stability are increased through the synergistic effect of different ceramics, 20 Microcracks and thermal fatigue problems resulting from matrix-reinforcement mismatch. is being reduced. Another aim of the invention is to minimize fluctuations in the coefficient of friction on the brake pad surface. The integration of solid lubricant phases such as graphite and MoS₂ is used to minimize this. This approach is 25 Thanks to this, the coefficient of friction is in the range of ±6% under high temperature and high speed conditions. This ensures stability and prevents sudden performance drops. Another aim of the invention is to create a three-dimensional system that will ensure a homogeneous distribution of particle sizes. It involves mixing and high-pressure cold pressing steps. This provides reinforcement and... Matrix components are not evenly distributed, preventing uneven wear problems caused by agglomeration. 30 The problem is eliminated, and surface wear resistance is increased. Another objective of the invention is sintering, preferably carried out at 900 °C in an argon atmosphere. The aim of this process is to ensure the formation of strong bonds between the metal matrix and the reinforcement phases. 6 As a result, mechanical strength increases and structural integrity is maintained in high-temperature cycles. It is protected. Another aim of the invention is to improve ease of production and industrial scalability in brake pads. The aim is to make it possible. The powder metallurgy, cold pressing and sintering processes used are currently 5. Because it is compatible with industrial infrastructure, it can be directly adapted to mass production and Cost effectiveness is ensured. Another aim of the invention is to achieve long-term stability in braking performance and The maintenance intervals are extended. This reduces operating costs and also saves passengers 10 Security is being maximized. All the purposes mentioned above and those that will emerge from the detailed explanation below. The present invention aims to achieve high friction stability in high-speed trains. Cu-Fe based hybrid ceramic 15 providing low wear rate and high temperature resistance This relates to the production method of reinforced composite brake pads. The method in question is fundamentally based on... In this case, it includes the following steps:  High levels of copper, ranging from 55–68% by weight, and iron, ranging from 10–22%. Metal matrix mixture by weighing Cu and Fe powders with ≥99% purity creation; 20  Graphite powder in the range of 5–15% and molybdenum disulfide (MoS₂) powder in the range of 0.5–5% addition to the metal matrix mixture;  Hybrid ceramics selected from Al₂O₃+SiO₂, Al₂O₃+ZrO₂, Al₂O₃+SiC combinations Each of the phases is added to the metal matrix mixture in the range of 2–8%. to be done; 25  Homogenizing the resulting powder mixture,  Molding of homogeneous powder mixture by cold pressing process;  The sample taken from the mold is subjected to an inert gas atmosphere at a temperature range of 850–950 °C. sintering;  Controlled cooling of the sintered sample. 30 7 The preferred applications of the invention are; homogenization of powder mixtures using three-component systems. in a axially moving mixing device at a speed of at least 75 rpm for at least 2 hours This involves mixing the particles to homogenize their distribution. The preferred applications of the invention are; homogenization of the powder mixture and then processing of the mixture. Thermal analysis was performed using TGA / DTA tests, and the diffusion reached its maximum level at 5. This includes verifying the temperature range. The preferred applications of the invention are; selecting the homogeneous mixture in the cold pressing step. Placed in brake pad molds and subjected to a pressure of at least 600 MPa for at least 1 minute. It involves compression. The preferred applications of the invention are; pressing samples in the sintering step with argon 10 It involves sintering in a furnace at 900 °C for 1 hour in an atmospheric environment. The preferred applications of the invention are: after sintering in the controlled cooling step. the samples are cooled to room temperature in a controlled manner inside the oven. It includes. Preferred applications of the invention; Hybrid composite produced after cooling process 15 Brake pads undergo density, hardness (HBW), wear resistance, and coefficient of friction (COF) tests. This involves verifying their performance through monitoring. The best way to utilize the advantages of the existing invention, together with its structure and additional elements. For it to be understood, it must be considered together with the figures explained below. Brief Description of the Figures Figure 1: The subject of the invention is the production of Cu-Fe based hybrid ceramic reinforced composite brake pads. The method is shown in a flowchart view. Figure 2: Graph of TGA / DTA analysis of the SiO2-doped mixture. Figure 3: Graph of TGA / DTA analysis of the ZrO2-doped mixture. 25 Figure 4: Graph of TGA / DTA analysis of SiC-reinforced mixture. Reference Numbers S1 – Preparation of Metal Matrix Powders S2 – Addition of Solid Lubricants S3 – Addition of Hybrid Ceramic Reinforcements 30 8 S4 – Homogenization of the Powder Mixture S5 – Performing Thermal Analyses S6 – Cold Pressing Process S7 – Sintering Step S8 – Controlled Cooling Process 5 S9 – Conducting Performance Tests Detailed Description of the Invention This detailed explanation focuses solely on the innovation in the invention to provide a better understanding of the subject matter. This is explained with examples that will not create any limiting effect. Accordingly, the following: In the descriptions and diagrams, high friction stability and low wear are emphasized in high-speed trains. Cu-Fe based hybrid ceramic reinforced composite providing high ratio and high temperature resistance. The manufacturing method of brake pads is explained. Figure 1 shows the flowchart view of the production method related to the invention. Accordingly, the invention Subject of the method; 15 (S1) – Preparation of Metal Matrix Powders (S2) – Addition of Solid Lubricants (S3) – Addition of Hybrid Ceramic Reinforcements (S4) – Homogenization of the Powder Mixture (S5) – Performing Thermal Analyses 20 (S6) – Cold Pressing Process (S7) – Sintering Step (S8) – Controlled Cooling Process (S9) – Conducting Performance Tests It includes the steps of the process. 25 (S1) In the step of preparing metal matrix powders; copper should be 55–68% by weight and iron should be... High purity (≥99%) Cu and Fe powders are weighed to be in the range of 10–22%. A matrix mixture is being formed. (S2) In the step of Adding Solid Lubricants, graphite metal matrix 30 in the range of 5–15% of powder and 0.5–5% of molybdenum disulfide (MoS₂) powder by adding it to the mixture, the stability of the coefficient of friction at high temperatures (S3) In the step of Adding Hybrid Ceramic Reinforcements, Al₂O₃+SiO₂ is supported. 2–8% of each of the hybrid ceramic phases selected from Al₂O₃+ZrO₂ or Al₂O₃+SiC pairs. The powder is included in the mixture in such a way that it will be within the range of (S4). Powder Mixture During the homogenization step, all components are preferably mixed using a mixer with triaxial movement. 35 9 The particle distribution is ensured by mixing in the device at a speed of at least 75 rpm for at least 2 hours. (S5) In the step of Performing Thermal Analyses, the powder is homogenized. The mixture is preferably evaluated using TGA / DTA tests. The analysis results are as follows: Binding and moisture removal occurs in the 200–300 °C range, and surface treatment occurs in the 450–550 °C range. 5 is the temperature at which the interaction begins and diffusion reaches its maximum level in the 850–950 °C range. This is confirmed. Thus, the sintering temperature can be selected in the range of 850–950 °C. (S6) In the cold pressing process step, the homogeneous mixture is pressed into the selected brake pad molds, preferably Ø10. Placed into metal molds with an inner diameter of mm, and subjected to a pressure of at least 600 MPa for at least 1 It is compressed for a period of minutes and its pre-density is achieved. (S7) Pre-density in the Sintering Step The samples, with the required density, were placed in an inert gas atmosphere such as argon or nitrogen at 850–950 °C. at least 1 hour within the temperature range; preferably 1 hour at 900 °C in an argon atmosphere. It is sintered; during this process, strong bonds are formed between the matrix and the hybrid ceramic reinforcements. (S8) Controlled Cooling Process; after sintering The samples were cooled to room temperature in the oven at a controlled cooling rate of 1–10 °C / min. By cooling it down, thermal stresses are minimized. (S9) Performance 15 In the testing phase, the density and hardness (HBW) of the produced hybrid composite brake pads were measured. wear resistance and coefficient of friction (COF) tests at 25 °C, 100 °C and 400 °C Their performance is preferably verified by subjecting them to these tests. The working principle of the production method that is the subject of the invention; Preparation of Metal Matrix Powders (S1) 20 With this step, the Cu-Fe matrix is ​​formed within the target composition window and tribological / thermal It begins with providing the basic structure that meets the requirements. Addition of Solid Lubricants Addition of graphite and MoS₂ in step (S2) results in transfer film formation and slippage at high temperatures. It serves to limit fluctuations in the coefficient of friction on its surface. Hybrid Addition of Ceramic Reinforcements (S3) provides superior hardness, wear resistance, and thermal properties compared to individual reinforcements. By providing stability synergy, expansion mismatches and microcracks are balanced. It contributes to reducing its formation. By homogenizing the powder mixture (S4). agglomeration is prevented by ensuring a uniform distribution of additives and lubricating phases within the matrix. Risks of uneven wear caused by sintering are reduced. Performing Thermal Analyses (S5), sintering This enables the selection of a safe and effective temperature window for bond formation; thus, bond formation occurs within 30°C. While maximizing, unwanted phase transformations are limited. Cold Pressing Process (S6), It provides the precondition for condensation by increasing mechanical locking and green part stability. Sintering Step (S7) creates structural bonds by forming strong bonds at metal-ceramic interfaces. It enhances integrity and load-carrying capacity. Controlled Cooling Process (S8), thermal By minimizing stresses, it reduces the risk of crack formation and distortion. Finally, 35 Performing Performance Tests (S9) including density, hardness, wear and multiple temperature COF measurements are performed at various levels to determine the product's targeted high friction stability. It is confirmed that the method meets the criteria of low wear and high temperature resistance; thus, the method chain, safe, stable and long-lasting braking system for high-speed train applications. It is completed in a way that will achieve its performance. In alternative applications of the method described in the invention; metal matrix hybrid composite brake pads. Reinforcement elements such as TiC, B4C, WC, etc., can be used in its production. These reinforcement elements have high... It can alter temperature stability or wear properties. In addition, the reinforcing element Reinforcements such as fibers or nano-sized powder materials can be used. This situation It can improve performance but increase production costs. Metal matrix hybrid 10 Hexagonal boron nitride (h-BN) is used instead of graphite as a solid lubricant in the production of composite brake pads. It can be used in the production of metal matrix hybrid composite brake pads using a copper-iron based matrix. Bronze or brass alloys can be used instead. This results in improved strength and thermal conductivity. It changes the traditional oven used in the production of metal matrix hybrid composite brake pads. Induction sintering or spark plasma sintering (SPS) methods can be used. 15 The invention as a whole, including the matrix structure, reinforcement, and manufacturing method, is superior to that of train brake pads. heavy machinery requiring high performance, industrial cranes or lifting equipment, wind It can be used in industrial applications such as turbines, etc. EXAMPLES 20 The subject of the invention is the production of hybrid brake pad prototypes using high-purity (>99%) powder materials: 55–68% Cu, 10–22% Fe, 5–15% graphite, 0.5–5% MoS₂ by weight, with 2–8% for each phase. Al₂O₃+SiO₂, Al₂O₃+ZrO₂ or Al₂O₃+SiC ceramic reinforcements in the range Prepared by weighing the mixture in the specified proportions using a balance with a precision of 0.001 g. Homogeneous. To ensure even distribution, the mixtures are placed in a 25-degree rotating and agitating motion in two axes. The mixture was used in a three-dimensional mixing machine, rotating at 75 rpm for two hours. The process eliminates uneven wear problems that may arise from particle heterogeneity. It is of critical importance in terms of prevention. Thermogravimetric methods are used to study the thermal behavior of mixtures before sintering. Total Gas Analysis (TGA) and Differential Thermal Analysis (DTA) were performed. TGA results, 30 Organic binders and moisture in composites are completely eliminated in the temperature range of 200–300 °C. that it moves away, and that mass loss is negligible at high temperatures (<800 °C). DTA analyses have shown that reinforcement phases and metal matrix powders are in the 450–550 °C range. surface interactions begin between them and interphase diffusion occurs in the 850–950 °C range. 11 It has been shown that it has reached its maximum level. The most suitable value for sintering temperature. A temperature of 900°C was determined. The graphs for these analyses are presented in Figures 2–4. The prepared mixtures are poured into a powder metal mold with an inner diameter of Ø10 mm and pressed at a pressure of 600 MPa. It was pressed for one minute underneath and then held in the mold. This process separated the grains. It ensured the material's density by providing mechanical interlocking. The resulting 5 Compact samples were placed in a temperature-controlled oven under an argon atmosphere at 900 °C for one hour. The samples were sintered for a specified period. After the sintering process, the samples were placed in a furnace under controlled conditions. It has been cooled to room temperature. As a result of the sintering process, the metal matrix It has been observed that it condenses and forms strong bonds with the reinforcement phases. Ceramic reinforcements It increased surface hardness and wear resistance; structural integrity of solid lubricant phases 10 Friction stability at high temperatures has been ensured by protecting the produced hybrid composite. Friction coefficients based on density, hardness, and wear properties of brake pad samples. This is given in Table 1. Table 1. Performance characteristics of hybrid composite brake pad samples. Sample Intensity (g / cm³) Hardness (HBW 1 / 5.625) CoF (Pin- (on-Disk) CoF (25 °C) CoF (100 °C) CoF (400 °C) Cu-SiO₂ 4.571 23.6 0.152 0.252 0.568 0.534 Cu-ZrO₂ 4.819 23.3 0.269 0.310 0.579 0.474 Cu-SiC 4.649 24.4 0.352 0.341 0.465 0.448 In the hybrid composite brake pad samples obtained, density, hardness and wear properties were 15 The associated friction coefficients are given in Table 1. The measured hardness values ​​are 23.3–24.4 HBW. It is within this range, and stability has been achieved with a ±6% deviation in the coefficient of friction. In the literature... Compared to the 10–15% performance losses reported at high temperatures, this result is significant. It provides an improvement. The balanced distribution of powder materials with different expansion coefficients within the matrix, 20 It prevented microcrack formation in repeated thermal cycles; under intense braking conditions. It has contributed to preserving the structural integrity of the brake pads. The production method is currently in use. It is fully compatible with industrial powder metallurgy and sintering lines, and requires a dedicated infrastructure. It is not required. 12 These results demonstrate the following technical and economic advantages of the invention in practical applications: This shows that it provides: Extending maintenance intervals in railway transportation and Reducing operating costs, ensuring the stability of braking performance in high-speed trains. Increasing and improving safety, with the existing infrastructure, is a high priority for brake pad manufacturers. Making it possible to produce high-performance products. 5

Claims

13 REQUESTS 1. This is a production method for Cu-Fe based hybrid ceramic reinforced composite brake pads. Its feature is that it includes the following steps:  High levels of copper, ranging from 55–68% by weight, and iron, ranging from 10–22%. The metal matrix mixture is formed by weighing Cu and Fe powders with a purity (%≥99) and... creation (S1);  Graphite powder in the range of 5–15% and molybdenum disulfide (MoS₂) powder in the range of 0.5–5% addition to the metal matrix mixture (S2);  Hybrid ceramics selected from Al₂O₃+SiO₂, Al₂O₃+ZrO₂, Al₂O₃+SiC combinations 10% of each phase added to the metal matrix mixture, in the range of 2–8%. (S3);  Homogenization of the resulting powder mixture (S4),  Molding of homogeneous powder mixture by cold pressing process (S6);  The sample taken from the mold is subjected to an inert gas atmosphere at a temperature range of 850–950 °C. Sintering (S7); 15  Controlled cooling of the sintered sample (S8).

2. The method conforming to claim 1 is characterized by its ability to homogenize the powder mixture. The components are mixed in a three-axis mixing machine at a speed of at least 75 rpm. Mixing for at least 2 hours to homogenize the particle distribution (S4).

3. The method conforming to claim 1 or 2, characterized by: homogenization of the powder mixture from 20 Then, thermal analysis of the mixture is performed using TGA / DTA tests to determine diffusion. Verification of the temperature range at which it reaches its maximum level (S5).

4. The method conforming to Claim 1 is characterized by; homogeneous mixture during the cold pressing step. Placed in selected molds and subjected to a pressure of at least 600 MPa for at least 1 minute. It is compression (S6). 25 5. This method complies with Claim 1 and its characteristic is that the samples are pressed during the sintering step. It is sintered in a furnace at 900 °C for 1 hour in an argon atmosphere (S7). 14 6. A method conforming to Claim 1, characterized by: Sintering in a controlled cooling step. Afterwards, the samples are brought to room temperature in a controlled manner inside the oven. cooling (S8).

7. A method that complies with Claim 1, characterized by; a hybrid produced after the cooling process. Composite brake pads have a density, hardness (HBW), wear resistance, and friction coefficient of 5. Their performance is verified by subjecting them to (COF) tests (S9).

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