Alloy, fine blanking tool, powder pressing tool, stamping tool and cutting tool

Abstract

This invention relates to an alloy comprising, in weight percent (wt.%), the following: C 0.3 to 0.8, Si 0.1 to 1.8, Mn 0.1 to 1.3, Mo 15 to 23, B 1.1 to 2.8, Cr 2 to 9, Co 4 to 12, elements as appropriate, and the balance Fe excluding impurities.

Description

Technical Field

[0001] This invention relates to a wear-resistant steel alloy. The alloy is doped with boron and molybdenum to form hard phase particles. This invention also relates to precision blanking tools, powder pressing tools, stamping tools, or cutting tools comprising this alloy. Prior Technology

[0002] Nitrogen and vanadium alloyed powder metallurgy (PM) tool steels have gained considerable attention due to their unique combination of high hardness, high wear resistance, and excellent corrosion resistance. These steels have a wide range of applications, with the primary failure mechanisms being adhesive wear or abrasion. Typical applications include blanking and forming, precision blanking, cold extrusion, deep drawing, and powder pressing. Basic steel compositions are atomized, nitrided, and then the powder is packed into a cladding and subjected to hot isostatic pressing (HIP) to produce isotropic steels. High-performance steels produced in this manner are described in WO 00 / 79015 A1.

[0003] Despite the known attractive properties of steel, continuous efforts are made to improve tool materials in order to further enhance the surface quality of manufactured products and extend tool life. Specifically, good resistance to corrosion and wear is required under harsh working conditions. In many applications, materials must also be corrosion-resistant.

[0004] Wear-resistant alloys doped with boron to form hard phase particles are also known in this technology. US4318733 discloses commercial tool steels modified with 0.1 to 1.5 wt.% B. WO2016100374 A1, WO2018232618 A1, CN104846364 A and CN102619477 A are other examples of boron-doped tool steels. Lentz et al. (Steel Research International, 2020, Vol. 91, No. 5) have published results on the microstructure and properties of boron alloy tool steels containing Mo.

[0005] WO2016099390 A1 discloses a wear-resistant alloy containing boron and molybdenum, comprising a double boride of type M2M'B2, where M and M' represent various boride metals, with M being Mo and M' being Fe and / or Ni. According to WO2016099390 A1, the preferred maximum content of Co is 2%, due to Co's high cost and increased difficulty in waste disposal, and it is said that the intentional addition of Co is unnecessary. Summary of the Invention

[0006] The objective of this invention is to develop alloys with improved properties for advanced forming applications, such as precision stamping. Steels should also be better suited for gear cutting tools and end mills.

[0007] Another objective of this invention is to provide an alloy produced by powder metallurgy (PM) that has improved wear resistance in relation to both abrasive and adhesive wear.

[0008] By providing an alloy having the composition and microstructure as described in the claims, the aforementioned objectives and additional advantages are achieved to a significant extent.

[0009] The invention is defined in the scope of the patent application. Simple Explanation of the Diagram

[0010] [Figure 1] shows the microstructure of the alloy under soft annealing conditions. [Figure 2] shows the microstructure of the alloy after hardening and tempering. [Figure 3] shows the microstructure of the cast sample of the present invention. [Figure 4] shows the microstructure of the cast reference steel. Implementation

[0011] This invention relates to an alloy comprising a hard phase mainly composed of multiple borides of type M2M'B2. However, the borides may contain one or more of a large number of other boride-forming elements, such as Cr, Mo, W, Ti, V, Nb, Ta, Hf, and Co.

[0012] However, in the following text, the double boride will be referred to as Mo 2FeB 2, because the alloy is Fe-based. However, the boride may also contain Ni and one or more of the elements mentioned above that form borides.

[0013] The size of hard phase particles can be determined by microscopic image analysis. The size obtained is the equivalent circle diameter (ECD), which corresponds to the diameter of a circle with the same projected area as the particle.

[0014] The following briefly explains the importance of individual elements, their interactions, and the limitations on the chemical composition of the claimed alloy. Throughout the specification, all percentages of the steel's chemical composition are given in weight percent (wt.%). Upper and lower limits for individual elements can be freely combined within the limits set forth in the claims. For all values ​​given in this application, the arithmetic precision may be increased by one or two decimal places. Therefore, a value reported as, for example, 0.1% may also be expressed as 0.10% or 0.100%. The amounts of each phase are given in volume percent (vol.%). Upper and lower limits for individual elements can be freely combined within the limits set forth in the claims. [Carbon] (0.3 to 0.8%)

[0015] Carbon is essential for the hardening of tool steels. Preferably, the carbon content is such that 0.4 to 0.6% C dissolves in the matrix at the Worsfield tempering temperature, thereby producing a high-strength matrix after quenching. The Worsfield tempering temperature is preferably 1050 to 1120°C. In any case, the carbon content should be controlled to limit the amount of carbides in types M23C6, M7C3, M6C, M2C, and MC. The upper limit is 0.8%, and it can be set to 0.75%, 0.70%, 0.65%, 0.60%, or 0.55%. [Chromium] (2 to 9%)

[0016] Chromium is typically present in Fe-based alloys to provide sufficient hardenability. To achieve good hardenability, at least 2% Cr, preferably 2.5%, 3%, 3.5%, or 4% Cr, needs to be dissolved in the matrix. Cr is preferably above 3% to provide good hardenability in large cross-sections during heat treatment. Excessive chromium content can lead to the formation of undesirable carbides, such as M7C3. Additionally, it can increase the tendency for residual austenite in the microstructure. Lower limits can be set at 3.0%, 3.2%, 3.4%, 3.6%, 3.8%, 4.0%, or 4.2%. Upper limits can be set at 7.0%, 6.5%, 6.0%, 5.4%, or 4.6%. [Molybdenum] (15% to 25%)

[0017] Mo is the primary element for the formation of hard borides. In this invention, a large amount of molybdenum is used to obtain the desired precipitate of 15 to 35 vol.% boride, Mo₂FeB₂. Molybdenum should be present in an amount of at least 15%. The lower limit can be 16%, 17%, or 18%. The upper limit is 25% to avoid brittleness problems. The upper limit can be set to 24%, 23%, or 22%.

[0018] It has been reported that a Mo content of at least 10% has a beneficial effect on hardenability and achieves a good secondary hardening response (Lentz et al., Iron & Steel Research International, 2020, Vol. 91, No. 5). For this reason, it is preferable that the amount of Mo remaining in the matrix after quenching at 1100°C is 1.5% to 2.5%. However, excessive Mo dissolved in the matrix after hardening may lead to an excessive amount of residual woesfield iron and a decrease in hardness. Therefore, it is necessary to balance the Mo content with the Mo-containing hard boride phase, such that the matrix contains no more than 4% or 3.5% dissolved Mo, preferably no more than 3.2% Mo. The preferred range for dissolved Mo can be set to 2.1% to 3.1%. Therefore, the Mo / B ratio can be preferably adjusted to the range of 6 to 18, preferably 8 to 15, and more preferably 9 to 12. Another reason for balancing the Mo / B ratio is to avoid excessive molybdenum, which can lead to the formation of the hexagonal phase M₂C, where M is mainly Mo and / or V. M6C can also be formed, where M is mainly Mo and / or V. The amount of M6C and / or M2C can be limited to ≤5 vol%, preferably ≤4 vol.%, more preferably ≤3, or even further such as ≤1.5 vol.%, ≤1 vol.%, or ≤0.5 vol.%. [Boron] (1.1 to 2.8%)

[0019] Boron, as a nonmetallic element forming the hard phase, should be at least 1.1% to provide a minimum of 15% hard phase Mo₂FeB₂. The amount of B is limited to 2.8% to prevent the alloy from becoming brittle. The lower limit can be set at 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, or 2.0%. The upper limit can be set at 2.7%, 2.6%, 2.5%, 2.4%, 2.3%, or 2.2%. [Tungsten] (≤ 5%) []

[0020] Tungsten can be present in amounts up to 5%. Tungsten functions similarly to Mo. However, to achieve the same effect, twice the amount of W (by weight of Mo) must be added. Tungsten is expensive and also complicates the processing of scrap metal. Therefore, the maximum permitted amounts are limited to 3%, 2.5%, 2%, 1.9%, 1.8%, 1.7%, 1.6%, 1.5%, 1%, 0.5%, or 0.3%. Vanadium (≤ 5%) []

[0021] Vanadium forms uniformly distributed primary and secondary precipitated carbides of the MC type. In the steel of the present invention, M is mainly vanadium, but may contain certain amounts of Cr and Mo. The maximum addition of V is limited to 5%, and the preferred maximum amount is 1.5%. However, in the case of the present invention, V is mainly added to obtain the desired composition of the steel matrix before hardening. The addition can therefore be limited to 1.0%, 0.9%, 0.8%, 0.7%, 0.6% or 0.5%. The lower limit can be set to 0.05%, 0.1%, 0.12%, 0.14%, 0.16%, 0.15% or 0.2%. The preferred range is 0.1 to 0.5% V. [niobium] [(]≤ 5% [)] []

[0022] Niobium is similar to vanadium due to the formation of molybdenum (MC). However, to achieve the same effect, twice the amount of Nb (in weight percent of V) must be added. Nb also produces a more angular shape in the MC. Therefore, the maximum amount of Nb added is limited to 5%, with a preferred maximum of 1.5%. Upper limits can be set at 1%, 0.5%, 0.3%, 0.1%, or 0.05%. [Silicone] (0.1 to 1.8%)

[0023] Silicon can be used for deoxidation. Si also increases carbon activity and is beneficial for processability. To achieve good deoxidation, the Si content is preferably adjusted to at least 0.1%. Therefore, Si is preferably present in an amount of 0.1% to 1.5%. The lower limit can be set at 0.15%, 0.2%, 0.25%, 0.3%, 0.35%, or 0.4%. However, Si is a strong ferrite forming agent and should be limited to 1.8%. The upper limit can be set at 1.5%, 1%, 0.8%, 0.7%, or 0.6%. The preferred range is 0.2% to 0.8%. [Manganese] (0.1 to 1.3%)

[0024] Mn acts as a formant for ferrosilicon and increases the solubility of nitrogen in the alloy. Therefore, Mn can be present in a maximum amount of 1.3%. Manganese helps improve the hardenability of steel and, together with manganese sulfide, helps improve machinability by forming manganese sulfide. Manganese can therefore be present in a minimum content of 0.1%, preferably at least 0.2%. At higher sulfur contents, manganese prevents hot brittleness in steel. The upper limits can be set at 1.2%, 1.0%, 0.8%, or 0.6%. However, the preferred ranges are 0.2 to 0.8% and 0.2 to 0.6%. [Nickel] (≤ 10%) []

[0025] Nickel is added intentionally, but may be selected as appropriate, but in amounts up to 10%. Nickel shares many properties with Fe and can therefore partially replace iron in steel. Ni may preferably be intentionally added in amounts not exceeding 10%, 8%, 7%, or 5%. It imparts good hardenability and toughness to steel. Excessive Ni content may induce Vostian iron, a phase not desired according to the present invention. Due to cost, the nickel content is preferably limited. If not intentionally added, up to 3% Ni can be tolerated as an impurity. The upper limit may be set at 2%, 1.0%, or 0.3%. [iron] []

[0026] Iron is used as a surplus. [Copper] (≤ 5.0%) []

[0027] Cu is an element chosen on a case-by-case basis, which can help increase the hardness and corrosion resistance of steel. Upper limits can be 4%, 3%, 2%, 1%, 0.9%, 0.7%, 0.5%, 0.3%, or 0.1%. However, once copper is added, it is impossible to extract copper from steel. This greatly complicates waste disposal. For this reason, copper is generally not intentionally added. [Cobalt] (4 to 12%)

[0028] Co is present in amounts not exceeding 12%. Co dissolves in iron and strengthens it, while also imparting high-temperature strength. Co increases the Ms temperature and allows for higher quenching temperatures, and it is known to increase the red hardness in high-speed steel. Co enhances the Curie temperature, reduces diffusivity, and decreases the coarsening rate of carbide and / or nitride hard particles. Therefore, it is believed that Co increases tempering resistance. Co can partially replace Fe in Mo₂FeB₂ borides. Experiments have unexpectedly shown that the addition of Co increases the size of the primary boride, Mo₂FeB₂. The increased boride size can be beneficial to wear resistance. The addition of Co further inhibits the formation of woesfield iron. However, Co is expensive. The upper limit can therefore be set at 11%, 10%, or 9%. The lower limit can be 4%, 5%, 6%, or 7%. [Phosphorus] (≤0.1%)

[0029] Phosphorus (P) is an impurity element and a solid solution reinforcing element. However, P tends to separate grain boundaries, reducing cohesion and thus toughness. Therefore, P is usually limited to ≤0.05%. [Sulfur] (≤ 0.5%)

[0030] Sulfur (S) helps improve the machinability of steel. However, higher sulfur contents pose a risk of hot brittleness. Furthermore, high sulfur content may negatively impact the fatigue properties of steel. Therefore, steel should contain ≤ 0.5%, preferably ≤ 0.1%, and more preferably ≤ 0.03%. [Nitrogen] (≤ 0.5%)

[0031] Nitrogen is a component to be selected as appropriate. N can exist in solid solutions, but can also be found in hard phase particles along with B and C. The upper limits are 0.4%, 0.3%, 0.2%, 0.15%, 0.1%, 0.05% and 0.03%. [Aluminum] (≤0.1%)

[0032] Al can be added to deoxidize the alloy. The upper limit is 0.1%, but it can be set to 0.08%, 0.06%, or 0.05%.

[0033] The lower limit for deoxygenation can be set to 0.005%, 0.01%, or 0.03%.

[0034] In detail, steel can be used in additive manufacturing (AM) in powder form using commercially available units for laser melting or electron beam melting. Therefore, steel can be used to provide a wear-resistant cladding on substrates. Powder can also be used for flame spraying, surface hardening treatments, and the like. Examples of suitable additive manufacturing methods include, but are not limited to: Selective laser melting (SLM), Direct Metal Deposition (DMD), Direct Metal Laser Sintering (DMDS), and electron beam additive manufacturing.

[0035] The alloy is composed of the following components, expressed in weight percent (wt.%): C 0.3 to 0.8 Si 0.1 to 1.8 Mn 0.1 to 1.3 Mo 15 to 23, B 1.1 to 2.8 Cr 2 to 9 Co 4 to 12 Choose according to the situation. V ≤5、 Nb ≤5、 Cu ≤5 W ≤5、 S ≤0.5 N ≤ 0.5 Al ≤0.1 Ni ≤10、 The remaining Fe after removing impurities.

[0036] Alloys can be produced by powder metallurgy, preferably by gas atomization. microstructure

[0037] The gas-atomized alloy may contain 15 to 35% by volume of at least one of borides, nitrides, carbides, and / or combinations thereof as hard phase particles. Preferably, at least 60% of the hard phase particles consist of Mo₂FeB₂ or Mo₂NiB₂, and at least 90% of the hard phase particles are smaller than 5 μm. More preferably, at least 50% of the hard phase particles have a size in the range of 0.3 to 3 μm. It is also more preferably that the Mo / B ratio is adjusted to the range of 6 to 18, and the matrix of the alloy contains no more than 4% Mo.

[0038] The steel composition and heat treatment can be selected to give the steel a tempered martensitic matrix. The amount of residual martensitic iron in the martensitic matrix can be limited to 10 vol.%, 5 vol.%, or 2 vol.%. The alloy can be prepared under hardening and tempering conditions to be free of residual martensitic iron. Hard phase particles can be embedded in the martensitic matrix.

[0039] Therefore, the microstructure under hardening and tempering conditions can include the following components, expressed in vol%: Hard phase particles 15 to 35 Residual ferrous iron ≤10 The remaining amount is recycled from the hemp field.

[0040] Hard phase particles and tempered ferroalloys can be determined, for example, using a scanning electron microscope (SEM) at 1500x magnification. Residual ferroalloys can be determined using an X-ray diffractometer according to ASTM E975-13.

[0041] Under hardening and tempering conditions, the alloy can achieve a hardness greater than 65 HRC. The hardness is affected by the Worsfield ferroplating conditions during hardening and tempering. A hardness of at least 68 HRC, preferably at least 69 HRC, and most preferably at least 70 HRC can be achieved. Rockwell hardness can be determined using ASTM E18-00.

[0042] Under hardening and tempering conditions, the alloy can exhibit a compressive yield strength exceeding 3000 MPa. Preferably, it is in the range of 3200 to 4000 MPa, more preferably 3500 to 3900 MPa. The modulus of elasticity can exceed 230,000 MPa, more preferably 240,000 to 270,000 MPa. These equivalent values ​​can be derived from the methods described in ASTM E9-19 and ASTM E 111-17.

[0043] Under soft annealing conditions, the alloy can have a hardness ranging from 250 to 400 HB, preferably from 300 to 350 HB. Brinell hardness can be determined by ASTM E10-15.

[0044] Alloys can be manufactured by atomizing molten material with gas.

[0045] The powder can be sieved (e.g., <500 μm) and filled in a steel cladding, and subjected to hipping at a temperature in the range of 1000 to 1300 °C, preferably 1100 to 1200 °C. The holding time can be, for example, 1 to 3 hours, and the pressure can be, for example, 90 to 150 MPa. The cooling rate can be < 10 °C / s, typically 1 °C / s. The steel can be forged at 1000 to 1200 °C, followed by soft annealing at 800 to 1000 °C, typically about 900 °C, reduced to 600 to 800 °C by a cooling rate of 5 to 20 °C / h, and then free-cooled in air. Example 1

[0046] Alloy A is melted and subjected to gas atomization.

[0047] The atomized alloy has the following composition, expressed as a percentage by weight: C 0.51 Si 1.06 Mn 0.29 Cr 4.21, Mo 17.34, B 1.59、 Ni 0.04 V 0.26、 W 0.06 Cu 0.13 Co 8.52, N 0.02、 P 0.013 S 0.009, Fe, excluding impurities.

[0048] The powder was sieved to <500 μm, filled in a steel sheath, and subjected to hipping at 1150°C for 2 hours at a pressure of 110 MPa. The cooling rate was <1°C / s. The resulting material was then forged to a size of 20 × 30 mm at 1100°C. Soft annealing was performed at 900°C, followed by a cooling rate of 10°C / h to 750°C, and then free-cooling in air. Under soft annealing conditions, the hardness was measured to be 335 HB. Figure 1 shows the microstructure under soft annealing conditions at 2000x magnification.

[0049] Hardening was achieved by ferroplating at 1100°C for 30 minutes in a vacuum furnace, followed by high-pressure gas quenching with nitrogen. The steel was tempered three times at different temperatures, each time for 1 hour (3 × 1 h). The hardness test results after tempering are provided in Table 1. The ductility, compressive yield strength, and modulus of elasticity of the steel tempered at 520°C and 560°C were determined, and the results are shown in Table 1. For all tempering temperatures, the amount of residual ferroplatin in the ferroplatin matrix was determined to be less than 2 vol.%. Figure 2 shows the microstructure at 1500x magnification after three temperings at 560°C. The microstructure contains 23% hard phase particles from the tempered ferroplatin matrix. Tempering temperature (°C) Hardness (HRC) Extensibility (J) Compressive yield strength Rc 0.2 (MPa) Elastic modulus (MPa) 510 69.8 520 70.0 12.7 3768 245630 530 69.7 540 69.0 550 68.5 560 68.0 14.9 3654 249847 570 67.0 Table 1. Hardness changes with tempering temperature after hardening at 1100℃.

[0050] Therefore, tempering at approximately 520°C is recommended for optimal abrasion resistance and highest compressive strength, and tempering at approximately 560°C is recommended if higher ductility is required. Example 2

[0051] Alloy B is melted and subjected to gas atomization.

[0052] The powder was sieved to <500 μm, filled in a steel sheath, and subjected to hipping at 1100°C for 4.5 hours at a pressure of 100 MPa. The cooling rate was <1°C / s. The resulting material was forged into rods with a diameter of 142 mm at 1100°C. Soft annealing was performed at 900°C, followed by a cooling rate of 10°C / h to 750°C, and then free-cooling in air.

[0053] Hardening was achieved by ferroplating at 1100°C for 30 minutes in a vacuum furnace, followed by high-pressure gas quenching with nitrogen. The steel was then tempered three times at 560°C for 1 hour each time (3 × 1 h).

[0054] The atomized alloy has the composition in weight percent according to Table 2B. Commercial alloys CPM® 15V and Vanadis® 8 were added as references. CPM® 15V and Vanadis® 8 were heat-treated according to Table 3. alloy C Si Mn Mo B Cr Co V Fe B 0.51 0.46 0.29 18.2 1.89 4.18 8.75 0.28 margin CPM® 15V 3.4 0.9 0.5 1.3 - 5.25 - 14.5 margin Vanadis® 8 2.3 0.4 0.4 3.6 - 4.8 - 8.0 margin Table 2

[0055] Abrasion resistance was tested by contacting SiO2 paper and Al2O3 paper using a modified pin-disc method. Weight loss per minute was measured. The results are shown in Table 3. alloy Heat treatment Hardness HRC Mg / min SiO 2 Mg / min Al₂O₃ B 1100℃+560℃ / 3×1h 68.5 1.1 32.2 CPM® 15V 1120℃+540℃ / 3×2h 61.4 2.7 36.0 Vanadis® 8 1100℃+540℃ / 3×1h 62.2 10.3 83.6 Table 3

[0056] As can be seen, the alloy of this invention has significantly better wear resistance compared to commercial-grade CPM® 15V and Vanadis® 8. Example 3

[0057] The effect of cobalt addition was investigated. Cast samples of alloy B and reference alloy C were produced according to Table 4. The only difference between alloys B and C was the cobalt content. C Si Mn Mo B Cr Co V Fe B 0.5 0.5 0.3 18.3 1.9 4.2 8.8 0.3 margin C 0.5 0.5 0.3 18.3 1.9 4.2 - - margin Table 4

[0058] Figure 3 reveals the microstructure of alloy B, which was hardened in a vacuum furnace at 1100°C for 30 minutes, followed by high-pressure gas quenching with nitrogen, and then tempered three times at 525°C for 1 hour each time. The hardness before and after tempering was 70 HRC. The magnification in the figure is 500x.

[0059] Figure 4 reveals the microstructure of alloy C, which was hardened in a vacuum furnace at 1100°C for 30 minutes, followed by high-pressure gas quenching with nitrogen and then tempered three times at 525°C for 1 hour each time. The hardness before tempering was 69 HRC and the hardness after tempering was 66 HRC. The magnification in the figure is 500x.

[0060] As can be seen from the comparison between B and C, the addition of cobalt not only improves hardness but also tempering resistance. Furthermore, a comparison between Figures 3 and 4 visually reveals that the addition of cobalt significantly increases the size of the major borides in alloy B. It is believed that the increased hardness and size of the major borides are the main reasons for the high wear resistance of alloy B. Industrial applicability

[0061] The alloys of this invention are suitable for a wide range of applications. Specifically, the steel is suitable for applications requiring extremely high wear resistance and / or resistance to adhesive wear, such as precision stamping. The alloys are further suitable for cutting tools, such as grinding and thread-cutting tools, specifically end mills, gear cutting tools, and thread cutters. Another example of a cutting tool is a veneer cutter. The alloys are further suitable for stamping, including laminating dies. The alloys are further suitable for powder pressing tools.

[0062] none

Claims

1. An alloy comprising, in weight percent (wt.%), the following: C 0.3 to 0.8, Si 0.1 to 1.8, Mn 0.1 to 1.3, Mo 15 to 23, B 1.1 to 2.8, Cr 2 to 9, Co 4 to 12, V ≤5, Nb ≤5, Cu ≤5, W ≤5, S ≤0.5, N ≤0.5, Al ≤0.1, Ni ≤10, with the balance being Fe excluding impurities, wherein the alloy has a hardness of at least 68 HRC after hardening and tempering.

2. The alloy of claim 1 contains at least one of the following components in weight percent (wt.%): C 0.4 to 0.6, Si 0.2 to 1.3, Mo 16 to 23, B 1.2 to 2.4, Cr 3 to 8, Co 6 to 12, V ≤1.5, Nb ≤1.5, W ≤1, S ≤0.05, Ni ≤5.

3. The alloy as claimed in item 1, comprising the following in weight percent (wt.%): C 0.45 to 0.65, Si 0.4 to 1.2, Mn 0.2 to 0.5, Mo 15 to 23, B 1.4 to 2.2, Cr 3 to 6, Co 7 to 10, V 0.05 to 0.5, Ni ≤1.

4. The alloy of claim 1, wherein the alloy is subjected to hardening and tempering conditions and its hardness is at least 69 HRC.

5. The alloy of claim 4, wherein the alloy has a hardness of at least 70 HRC.

6. The alloy of claim 2, wherein the alloy is subjected to hardening and tempering conditions and its hardness is at least 69 HRC.

7. The alloy of claim 6, wherein the alloy has a hardness of at least 70 HRC.

8. The alloy of claim 3, wherein the alloy is subjected to hardening and tempering conditions and its hardness is at least 69 HRC.

9. The alloy of claim 8, wherein the alloy has a hardness of at least 70 HRC.

10. An alloy as claimed in any one of claims 1 to 9, wherein the alloy satisfies at least one of the following conditions: the alloy contains 15 to 35% by volume of hard phase particles, the hard phase particles contain at least one of borides, nitrides, carbides and / or combinations thereof, at least 90% of the hard phase particles are less than 5 μm in size, and at least 50% of the hard phase particles are in the range of 0.3 to 3 μm in size and at least 60% of the hard phase particles are composed of Mo2FeB2 or Mo2NiB, the matrix of the alloy contains no more than 4% Mo, and the alloy contains no more than 5% residual austenite.

11. A precision stamping tool comprising an alloy as claimed in any one of claims 1 to 10.

12. A powder pressing tool comprising an alloy as claimed in any one of claims 1 to 10.

13. A stamping tool comprising an alloy as claimed in any one of claims 1 to 10.

14. A cutting tool comprising an alloy as claimed in any one of claims 1 to 10.

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