Tools and methods for manufacturing the same

Abstract

The present invention relates to a tool comprising a cemented carbide section and a steel section joined by brazing, the steel section having an average hardness of 390-510 HV30. The braze joint comprises a TiC layer of 0.03-5 μm thickness adjacent to the Ti and cemented carbide sections. The tool provides a strong braze joint and a steel section with uniform hardness.

Description

Technical Field

[0001] The present invention relates to a tool including a cemented carbide part and a steel part, wherein the parts are joined by brazing. The present invention also relates to the manufacture of such tools.

Background Art

[0002] Joining steel to cemented carbide by brazing or welding has been known for a long time in the field of tool manufacturing. When joining steel to cemented carbide, there are several problems, for example, differences in CTE (coefficient of thermal expansion), the strength of the brazed joint, and an undesirable hardness profile of the steel.

[0003] There are several solutions that can individually improve each of these problems, but these solutions often cause problems in other areas and not all problems can be solved.

[0004] The principle of brazing is to use a brazing material that joins two parts when heated. There are several ways to heat the brazed joint, and one of the most common methods is induction heating using an induction coil. One of the advantages of using a coil is that only the local area around the brazed joint is heated, leaving the rest of the tool unaffected. However, this local heating can result in an undesirable hardness profile in the steel part and may cause problems when threading or the like provided in the steel part for fixing a rotary insert and other cutting tools.

[0005] Another disadvantage of using a coil for heating is that each tool needs to be handled individually, and a more automated industrial process is preferred.

[0006] Heating the entire steel and cemented carbide parts makes the hardness profile more uniform, but then the elevated temperature affects the entire steel part and thus reduces the overall hardness.

[0007] Another problem that can arise when threading is applied to steel parts to secure cutting tools is wear. Since it is preferable to use the same tool, such as the shank, for a long period of time, cutting tools are replaced frequently, and thread wear can negatively affect the securing of the cutting tool.

[0008] One object of the present invention is to provide a tool having both a robust brazed joint and a steel portion with a uniform hardness profile and high hardness, resulting in improved wear resistance.

[0009] Another object of the present invention is to provide an easy-to-use method for joining steel and cemented carbide, resulting in a high-strength, predictable joint and a steel portion with predictable hardness. [Brief explanation of the drawing]

[0010] [Figure 1] This figure shows an SEM image of a brazed joint according to the present invention at a magnification of 1000. A is the steel portion, B is the brazed joint, C is the cemented carbide portion, and D is the TiC layer. [Figure 2] This figure shows an SEM image of a brazed joint according to the present invention at a magnification of 1500. [Figure 3] This figure shows an SEM image of a brazed joint according to the present invention at a magnification of 10,000, where B is the brazed joint, C is the cemented carbide portion, D is the TiC layer, and E is the Ti accumulation layer. [Figure 4] This figure shows an SEM image at a magnification of 10,000 at the contact surface between the brazed joint and the steel part of the brazed joint according to the present invention. A is the steel part, B is the brazed joint, and F is the TiC layer on the steel surface. [Figure 5] This figure shows the hardness profile of a tool using induction heating. A is the steel part, B is the brazed joint, and C is the cemented carbide. [Figure 6]This diagram shows the steps of the claimed method. A is the step of preparing the cemented carbide part, B is the step of preparing the steel part, C is the step of placing the brazing material between the cemented carbide part and the steel part, D is the brazing step, E is the quenching step, and F is the tempering step. [Modes for carrying out the invention]

[0011] The present invention relates to a tool comprising a cemented carbide portion and a steel portion, wherein the steel portion has a composition of 0.63 to 0.70 wt% C, 1.40 to 1.60 wt% Si, 1.35 to 1.55 wt% Mn, 1.00 to 1.20 wt% Cr, 0.23 to 0.27 wt% Mo, less than 0.25 wt% Ni, less than 0.025 wt% P, less than 0.0015 wt% S, and the remainder Fe. The steel portion has an average hardness between 390 and 510 HV30 with a standard deviation between 0 and 30 HV30. The tool further comprises a brazed joint joining the cemented carbide portion and the steel portion, the brazed joint comprising Ti, and the brazed joint comprising a TiC layer adjacent to the cemented carbide portion with a thickness between 0.03 and 5 μm.

[0012] The cemented carbide parts can be manufactured from any cemented carbide commonly used in the art. The cemented carbide consists of a hard phase embedded in a metallic binder phase matrix.

[0013] In this specification, cemented carbide means that at least 50 wt% of the hard phase is WC.

[0014] Preferably, the amount of the bonding metal phase is between 3 and 20 wt%, more preferably between 4 and 15 wt%, of the cemented carbide. Preferably, the main component of the bonding metal phase is selected from one or more of Co, Ni, and Fe, and more preferably, the main component of the bonding metal phase is Co.

[0015] In this specification, "main component" means that no other elements are added to form the binder phase; however, if other components such as Cr are added, they will inevitably dissolve into the binder during sintering.

[0016] In one embodiment of the present invention, the cemented carbide may also contain other components common in cemented carbide elements, selected from Cr, Ta, Ti, Nb, and V, which exist as elements or as carbides, nitrides, or carbonitrides.

[0017] The steel portion according to the present invention preferably contains 0.63 to 0.70 wt% C, 1.40 to 1.60 wt% Si, 1.35 to 1.55 wt% Mn, 1.00 to 1.20 wt% Cr, 0.23 to 0.27 wt% Mo, less than 0.25 wt% Ni, less than 0.025 wt% P, and less than 0.015 wt% S. The remainder is Fe.

[0018] The average hardness of the steel portion is preferably between 390 and 510 HV30, and more preferably between 420 and 480 HV30. Hardness is measured using a Vickers hardness tester with a load of 30 kgf (kilogram-force) and a loading time of 15 seconds. A 3x3 pattern of indentations was applied to the cross-section of the steel portion. The average value is the average of these measurement points. The standard deviation of the hardness values ​​is preferably between 0 and 30 HV30, and more preferably between 0 and 15 HV30.

[0019] Brazing is a so-called active brazing technique. This means that the joint is formed not only by melting the brazing materials to form a metallic bond, but also by a chemical reaction with one or both of the materials being joined. The reactive element in the brazing material is usually Ti, but elements such as Hf, V, Zr, and Cr are also considered active elements. According to this invention, Ti is the active element.

[0020] In this specification, a brazed joint means the area or mass between a cemented carbide portion and a steel portion that is filled with brazing material and formed during the brazing process; see below.

[0021] The thickness of the brazed joint is preferably between 20 and 200 μm, more preferably between 30 and 100 μm.

[0022] The brazed joint is not a uniform phase. Rather, after brazing, the elements in the brazing material form different phases.

[0023] The brazed joint preferably contains Ti. During brazing, Ti reacts with carbon in the cemented carbide part to form a TiC layer on the contact surface between the brazed joint and the cemented carbide part.

[0024] There are several ways to detect the presence of the TiC layer, depending on the type of equipment used.

[0025] When using a scanning electron microscope (SEM) with a sufficiently high resolution, the TiC layer is clearly visible adjacent to the cemented carbide part. To confirm that it is the TiC layer, SEM-EPMA equipped with EDS or WDS can be used.

[0026] If the SEM used does not have a sufficient resolution to show the TiC layer, the accumulation of Ti and / or C at the contact surface between the brazing material and the cemented carbide can be seen using, for example, SEM-EDS or SEM-EPMA equipped with WDS. The accumulation of Ti is hereinafter referred to as the Ti accumulation layer and is a good indicator that a TiC layer is formed even if it is not visually detected in the SEM image. The Ti accumulation layer is considerably thicker than the actual TiC layer, which may mean that not all Ti forms TiC. The thickness of the Ti accumulation layer is also affected, at least in part, by the analytical method.

[0027] In one embodiment of the present invention, the thickness of the TiC layer is between 0.03 and 5 μm, more preferably between 0.05 and 0.5 μm, and most preferably between 0.05 and 0.25 μm.

[0028] Preferably, the brazed joint further comprises one or more elements selected from Zn, Ag, Cu, Sn, In, Zr, Hf, and Cr. More preferably, from Ag, Cu, and In, and most preferably from Ag and Cu.

[0029] Determining the composition of a brazed joint after brazing is difficult because the elements are not uniformly distributed. Ideally, since the paste or foil is a uniform blend, the easiest method is to examine the brazing material used. Furthermore, the brazed joint may contain small amounts of elements from the materials being joined, such as Co, Ni, Fe, and W from cemented carbide, and Fe and Ni from steel.

[0030] The amounts of Ti and other elements in the brazed joint can also be measured using energy-dispersive X-ray spectroscopy (EDS). However, due to the non-uniform distribution of elements in the brazed joint, many measurement points are required, resulting in a large standard deviation. Preferably, the brazed joint contains, on average, 30-80 wt%, preferably 40-75 wt%, of Ag, 15-65 wt%, preferably 20-40 wt%, of Cu, 0-15 wt%, of In, and 0.3-15 wt%, preferably 0.5-5 wt%, of Ti.

[0031] The brazed joint preferably has a shear strength of at least 130 MPa, preferably at least 140 MPa, and more preferably between 140 and 300 MPa. The shear strength is measured by a shear test.

[0032] At the contact surface between the brazed joint and the steel portion, Ti accumulates in the brazed joint as well, forming a TiC layer. The thickness of this TiC layer at the steel contact surface is preferably between 1 and 10 μm, preferably between 2 and 5 μm, and can be measured, for example, by SEM-EDS.

[0033] The tool may be any tool or part of a tool common in the art, in which a cemented carbide part is joined to a steel part by brazing. Specific examples include drills, end mills, and tool holders such as shanks.

[0034] In one embodiment of the present invention, the tool is a shank used as a tool holder for cutting tools such as insert tools and drill heads. The shank is formed of a cemented carbide portion and a steel portion, the cemented carbide portion being used to generate stability and the steel portion being necessary to generate threads for securing the cutting tool.

[0035] The present invention relates to a method for manufacturing a tool according to the above, comprising the following steps: - The process of preparing the cemented carbide parts; - A process of preparing a steel part having a composition of 0.63~0.70 wt% C, 1.40~1.60 wt% Si, 1.35~1.55 wt% Mn, 1.00~1.20 wt% Cr, 0.23~0.27 wt% Mo, less than 0.25 wt% Ni, less than 0.025 wt% P, less than 0.0015 wt% S, and the remainder Fe. - A process of placing a brazing material containing Ti in an amount of 0.3 to 15 wt% between the cemented carbide part and the steel part, in contact with each other. - A process in which a cemented carbide part and a steel part, with brazing material in between, are subjected to a brazing process in a furnace at a temperature between 800 and 1100°C for a period between 5 and 60 minutes, and the brazing is performed in an inert atmosphere at a pressure between 10 and 400 mBar; - A process of subjecting the cemented carbide and steel parts, which have the brazed material in between, to a quenching process by introducing an inert gas into the furnace at a pressure of at least 400 mBar until the temperature reaches below 200°C after brazing. - A process of subjecting at least the steel part to a tempering process at a temperature between 300 and 700°C for 15 minutes and 3 hours. Includes.

[0036] The cemented carbide and steel parts have the compositions described above. Prior to brazing, the average hardness of the parts may differ from those described above, depending on the grade of the steel and whether or not the steel has been tempered.

[0037] The shape and size of the cemented carbide and steel parts depend on the type of tool to be manufactured.

[0038] The brazing material (also called filler metal or solder) according to the present invention contains, in total, 0.3 to 15 wt%, preferably 1 to 5 wt%, of Ti. The brazing material of the present invention preferably has a solidus temperature between 488 and 1123°C, more preferably between 650 and 850°C. Furthermore, the brazing material of the present invention has a liquidus temperature between 612 and 1180°C, more preferably between 750 and 900°C. In addition to Ti, the brazing material further contains one or more elements selected from Zn, Ag, Cu, Sn, In, Zr, Hf, and Cr, more preferably Ag, Cu, and In, most preferably Ag and Cu.

[0039] In one embodiment of the present invention, the brazing material comprises 30-80 wt%, preferably 40-75 wt%, of Ag; 15-65 wt%, preferably 20-40 wt%, of Cu; 0-15 wt%, of In; and 0.3-15 wt%, preferably 0.5-5 wt%, of Ti.

[0040] In one embodiment of the present invention, the brazing material comprises 55-75 wt% Ag, 20-30 wt% Cu, 0-15 wt% In, and 1-5 wt% Ti, preferably 65-75 wt% Ag, 25-30 wt% Cu, and 1-5 wt% Ti.

[0041] Preferably, the brazing material is provided as foil or paste.

[0042] The brazing material is provided on the joining surface between the cemented carbide portion and the steel portion.

[0043] The thickness of the brazing material before the brazing process depends on the type of material, i.e., foil or paste. When paste is used, sufficient material is applied to cover the surface to be brazed. Typically, the thickness is between 25 and 200 μm, preferably between 50 and 100 μm.

[0044] The part is then placed in a furnace with an inert environment, i.e., a minimum amount of oxygen. Preferably, the brazing temperature in the furnace is between 800 and 1100°C, preferably between 850 and 980°C. The time the part is exposed to the high temperature is between 5 and 60 minutes, preferably between 15 and 45 minutes. If the time at the high temperature is shorter, there is not enough time for the brazed joint to form and for the Ti to react to reach the desired strength of the brazed joint. If the time at the high temperature is longer, a brittle reaction region containing Ti grows uncontrolled, negatively affecting the properties of the joint, such as the shear strength.

[0045] Brazing is carried out in the presence of an inert gas, preferably argon, and preferably at low pressure. Preferably, the pressure is between 10 and 400 mBar, and more preferably between 20 and 200 mBar.

[0046] During brazing in the furnace, a clamping force may be applied to further strengthen the braze. In this specification, clamping force means applying force by pressing the steel portion and the cemented carbide portion against each other, preferably by placing an external weight on the carbide portion. The force acting on the brazed joint due to the weight of the cemented carbide portion or the steel portion depends on which portion is on top of the other, but these values ​​are not included.

[0047] In one embodiment, a clamping force is applied between 0.5 and 10 MPa, preferably between 2 and 8 MPa.

[0048] In one embodiment of the present invention, no tightening force is applied.

[0049] In this specification, quenching means rapidly cooling the cemented carbide and steel parts, which have brazing materials in between, by introducing an inert gas into a furnace after the brazing process. The inert gas may be one of Ar or N2, or a mixture thereof. The temperature must be lowered to below the temperature at which oxidation occurs. Preferably, the temperature in the furnace is lowered to below 200°C, preferably below 150°C, preferably at a rate of at least 30°C / min, more preferably at least 45°C / min. Free cooling in air may then be permitted.

[0050] After brazing, the part is subjected to a tempering process by exposing it to a high temperature between 300 and 700°C, preferably between 400 and 650°C, for a period between 15 minutes and 3 hours. Preferably, tempering is carried out in an inert atmosphere, for example, in Ar and / or N2. The exact time and temperature depend on the desired average hardness level of the steel part.

[0051] The brazing furnace used in this invention may be any furnace capable of providing well-controlled conditions with respect to pressure, heating rate, and cooling rate, as described above. The brazing and tempering processes can be carried out in the same furnace or in two separate furnaces.

[0052] Steel parts are commonly used in machining operations, such as threading. For steel parts to be machineable, their hardness cannot be too high, and to achieve the desired hardness and wear resistance in the final tool, a tempering process can be performed on the steel part before or after machining, depending on the type of steel grade selected.

[0053] In one embodiment of the present invention, tempering is performed directly after the brazing process, and any machining of the steel, such as threading, is performed on the already tempered steel, i.e., after the tempering process.

[0054] In another embodiment of the present invention, tempering is performed after any machining of the steel, such as threading. [Examples]

[0055] Example 1 (The present invention) Steel parts made from bearing steel grade Ovako 677, having a composition of 0.63-0.70 wt% C, 1.4-1.6 wt% Si, 1.35-1.55 wt% Mn, 1-1.2 wt% Cr, 0.23-0.27 wt% Mo, and the remainder Fe, were prepared together with cemented carbide parts having a composition of 10 wt% Co and the remainder WC.

[0056] The brazing material was prepared in paste form in an amount sufficient to cover the surfaces to be joined. The brazing material had a composition of 70 wt% Ag, 28 wt% Cu, and 2 wt% Ti.

[0057] The paste was placed between the steel part and the cemented carbide part, so that both parts were in contact with the paste. The assembled joint was then placed in a vacuum sintering furnace, PVA COV 231, where it was sintered for 10 minutes. -2 First, a vacuum of mBar was achieved to remove all oxygen, and then an inert atmosphere with 50 mBar of Ar gas was introduced. The temperature was first raised to 250°C and held for 5 minutes, then stopped again at 550°C for 5 minutes. The brazing temperature was maintained at 880°C for 30 minutes, and then the parts were quenched by flowing Ar gas into the furnace at a pressure of 600 mBar until the temperature dropped below 150°C.

[0058] After the brazing / quenching process, the brazed parts were subjected to a tempering process to maintain the hardness of the steel. The parts were placed in a furnace and heated to 550°C in an inert atmosphere of 50 mBar Ar for 30 minutes, after which they were cooled.

[0059] In this specification, this sample is referred to as Invention 1.

[0060] Example 2 (Comparison 2) A steel component manufactured in Uddeholm Idun, having a composition of 0.21 wt% C, 0.9 wt% Si, 0.45 wt% Mn, 13.5 wt% Cr, 0.2 wt% Mo, 0.6 wt% Ni, and 0.25 wt% V, with the remainder being Fe, was prepared together with a cemented carbide component having a composition of 10 wt% Co and the remainder being WC.

[0061] The brazing material was prepared in paste form in an amount sufficient to cover the surfaces to be joined. The brazing material had a composition of 70 wt% Ag, 28 wt% Cu, and 2 wt% Ti.

[0062] The paste was placed between the steel and cemented carbide parts, so that both parts were in contact with the paste. The assembled joint was then placed in a vacuum sintering furnace, PVA COV 231, where it was subjected to 10 -2 First, a vacuum of mBar was achieved to remove all oxygen, and then an inert atmosphere with 50 mBar of Ar gas was introduced. The temperature was first raised to 250°C and held for 5 minutes, then stopped again at 550°C for 5 minutes. The brazing temperature was maintained at 880°C for 30 minutes, and then the parts were quenched by flowing Ar gas into the furnace at a pressure of 600 mBar until the temperature dropped below 150°C.

[0063] After the brazing / quenching process, the brazed parts were subjected to a tempering process to maintain the hardness of the steel. The parts were placed in a furnace and heated to 550°C in an inert atmosphere of 50 mBar Ar, held for 30 minutes, then cooled to below 100°C, then heated again to 550°C, held for 30 minutes, and then cooled. Two tempering cycles are recommended for this type of steel. This sample is referred to as Comparative 1 in this specification.

[0064] Example 3 (Comparison) A steel component made from steel 1.6582 (34CrNiMo6) was prepared along with a cemented carbide component having a composition of 10 wt% Co, 0.4 wt% Cr, and the remaining WC.

[0065] The brazing material was Ag49Zn23Cu16Mn7.5Ni4.5 in wire form, applied as a ring with a diameter of 1-2 mm.

[0066] The parts were joined by rapidly heating the brazed joint to 700°C using induction heating with a coil and holding it for 15 seconds. After that, the powder was removed and the tool was allowed to cool to room temperature. Figure 5 shows the hardness values ​​of the steel part, where measurement points are placed along a line measuring the distance from the brazed joint of the steel part, across the brazed joint, to the cemented carbide part.

[0067] In this specification, this sample is referred to as Comparative 2.

[0068] Example 4 (Comparison) A steel portion made from carbon-hardening hot-work steel 1.2344 was prepared along with a cemented carbide portion having a composition of 10 wt% Co, 1 wt% other carbides, and the remainder WC.

[0069] The brazing material was prepared in the form of a foil with a thickness of 100 μm. The brazing metal had a composition of 100 wt% Cu. The melting temperature was 1085°C.

[0070] The foil was placed between the steel and cemented carbide parts, and the assembled joint was placed in the furnace. The temperature was initially raised to 650°C at a rate of 20°C / min and held for 5 minutes. Then the temperature was increased from 650°C to 1100°C at a rate of 10°C / min, which is the brazing temperature T. ろう付け I raised it up to T ろう付け The mixture was held for a residence time of 15 minutes, after which the parts were cooled to 850°C at a cooling rate of 50°C / min. From 850°C, an overpressure of 2 bar and 2500 minutes were applied. -1 The sample was rapidly cooled with N2 using the fan frequency.

[0071] Next, the cemented carbide-steel joint was tempered twice at 630°C for 2 hours each time, together with carbon-hardened hot-worked steel 1.2344.

[0072] In this specification, this sample is referred to as Comparative 3.

[0073] Example 5 Hardness was measured using a Vickers hardness tester, applying loads of 30 kgf (HV30) and 1 kgf (HV1). The load was applied for 15 seconds.

[0074] For Invention 1 and Comparative Example 2, SEM-EDS technology was used to analyze the contact surface between the brazed joint and the cemented carbide. The SEM used was the Oxford Instruments NordlysMax. 2 Equipped with an EBSD detector, Oxford Instruments X-Max N He was VP of Zeiss Sigma, providing EDS systems.

[0075] The thickness of the TiC layer in the brazed joints of Invention 1 and Comparative Example 1 was measured on SEM images at a magnification of 1000. The TiC layer was confirmed by visual appearance in backscattered electron mode. Figures 1 and 2 show SEM images of Invention 1 in which the TiC layer is clearly visible. The TiC layer thickness values ​​shown in Table 1 are all averages of three measurements taken from the center of the brazed joint, i.e., away from the edges.

[0076] Using EDS, Ti accumulation could be observed in SEM images and measured as a Ti accumulation layer. In this specification, the accumulation layer refers to the thickness of the accumulation observed in SEM images and confirmed by EDS; see Figure 3. The values ​​in Table 1 are approximate values ​​from visual inspection of SEM images and are therefore given as widths (intervals). TIFF0007871287000001.tif49170

Claims

1. Cemented carbide parts; The steel portion has a composition of 0.63–0.70 wt% C, 1.40–1.60 wt% Si, 1.35–1.55 wt% Mn, 1.00–1.20 wt% Cr, 0.23–0.27 wt% Mo, less than 0.25 wt% Ni, less than 0.025 wt% P, less than 0.0015 wt% S, and the remainder Fe; and has an average hardness between 390 HV30 and 510 HV30 with a standard deviation between 0 HV30 and 30 HV30; A brazed joint that joins the cemented carbide portion and the steel portion; A tool that includes, A tool wherein the brazed joint contains Ti, and the brazed joint includes a TiC layer adjacent to the cemented carbide portion with a thickness between 0.03 μm and 5 μm.

2. The tool according to claim 1, wherein the steel portion has an average hardness between 420HV30 and 480HV30 with a standard deviation between 0HV1 and 15HV1.

3. The tool according to claim 1 or 2, wherein the brazed joint has a thickness between 20 μm and 200 μm.

4. The tool according to any one of claims 1 to 3, wherein the brazed joint comprises Cu and Ag.

5. The tool according to any one of claims 1 to 4, wherein the brazed joint comprises a composition of 30 to 80 wt% Ag, 15 to 65 wt% Cu, 0 to 15 wt% In, and 0.3 to 15 wt% Ti.

6. A method for manufacturing a tool according to any one of claims 1 to 5, - The process of providing cemented carbide parts; - A step of providing a steel part having a composition of 0.63 to 0.70 wt% C, 1.40 to 1.60 wt% Si, 1.35 to 1.55 wt% Mn, 1.00 to 1.20 wt% Cr, 0.23 to 0.27 wt% Mo, less than 0.25 wt% Ni, less than 0.025 wt% P, less than 0.0015 wt% S, and the remainder Fe; - A process in which a cemented carbide part and a steel part having brazing material in between are subjected to a brazing process in a furnace at a temperature between 800°C and 1100°C for a period between 5 minutes and 60 minutes, wherein the brazing is performed in an inert atmosphere at a pressure between 10 and 400 mBar; - A step of subjecting the cemented carbide and steel parts, which have the brazed material in between, to a quenching process by introducing an inert gas into the furnace at a pressure of at least 400 mBar until the temperature reaches below 200°C after brazing, - A process of subjecting at least the steel part to a tempering process at a temperature between 300°C and 700°C for a period of 15 minutes and 3 hours. Methods that include...

7. A method for manufacturing a tool according to claim 6, wherein the brazing process is performed at a temperature between 850°C and 980°C for a period between 15 minutes and 45 minutes.

8. The inert atmosphere during brazing is Ar and / or N ２ A method for manufacturing the tool according to claim 6 or 7.

9. A method for manufacturing a tool according to any one of claims 6 to 8, wherein the temperature during quenching is reduced at a rate of at least 30°C / min.

10. The inert gas used to flow into the furnace during quenching is Ar or N ２ A method for manufacturing the tool according to any one of claims 6 to 9, wherein the tool is one of the following or a mixture thereof.

11. A method for manufacturing a tool according to any one of claims 6 to 10, wherein the tempering process is carried out at a temperature between 400°C and 650°C for a period between 15 minutes and 3 hours.

12. A method for manufacturing a tool according to any one of claims 6 to 11, wherein the brazing material has a solidus temperature between 488°C and 1123°C and a liquidus temperature between 612°C and 1180°C, and the brazing material further comprises, in addition to Ti, one or more elements selected from Zn, Ag, Cu, Sn, In, Zr, Hf, and Cr.

13. A method for manufacturing a tool according to any one of claims 6 to 12, wherein the brazing material comprises 30 to 80 wt% of Ag, 15 to 65 wt% of Cu, 0 to 15 wt% of In, and 0.3 to 15 wt% of Ti.

14. A method for manufacturing a tool according to any one of claims 6 to 13, wherein a clamping force of 0.5 to 10 MPa is applied during the brazing process.

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