Isothermal forging high-temperature die material for aero-engine and preparation method thereof

Abstract

This invention proposes a high-temperature isothermal forging die material for aero-engines and its preparation method, relating to the field of alloy smelting. The material comprises the following elements: C 0.06-0.17%, Cr 3.0-6.0%, Co 9.0-11.0%, W 14.0-17.0%, Mo 1.0-2.5%, Ta 2.5-4.0%, Nb 1.3-2.5%, Al 5.0-6.3%, Ti 1.1-1.7%, B 0.01-0.02%, Zr 0.03-0.08%, Re 0.20-0.75%, Mg 0.001-0.01%, Ce 0.001-0.01%, Y 0.001-0.01%, with the balance being Ni. By adding the high-melting-point solid solution strengthening element Re, the active element Mg, and the rare earth elements Ce and Y, the strength and plasticity of the alloy are improved, extending its service life.

Description

Technical Field

[0001] This invention relates to the field of alloy smelting, and more specifically, to a high-temperature isothermal forging die material for aero-engines and its preparation method. Background Technology

[0002] Isothermal forging is a precision forging technique. Its core lies in keeping the mold and the billet at the same constant temperature. By utilizing the superplastic conditions that occur when the metal material is under appropriate high temperature and stress for a long time through creep, or by utilizing materials that are sensitive to strain rate and phase transformation materials, thin-walled, high-ribbed, complex-shaped or difficult-to-deform metals can be formed.

[0003] Currently, commonly used isothermal forging die materials are K403 and K4002 alloys. These alloys can only meet the requirements for use at 1050℃ and cannot meet the isothermal forging requirements at 1100℃ and above. Although N3 alloy meets the isothermal forging requirements at 1100℃, its plasticity is relatively low, and the dies are prone to cracking after long-term use. Summary of the Invention

[0004] The purpose of this invention is to provide a high-temperature isothermal forging die material for aero-engines. This alloy material incorporates high-melting-point solid solution strengthening elements Re, active elements Mg, and rare earth elements Ce and Y, which further improves the strength and plasticity of the alloy at 1100℃ and extends the service life of the isothermal forging die.

[0005] Another objective of this invention is to provide a method for preparing high-temperature isothermal forging die materials for aero-engines, by adding raw materials and refining alloys in batches to improve the high-temperature strength and toughness of the materials.

[0006] The technical problem solved by this invention is achieved by the following technical solution.

[0007] On one hand, embodiments of the present invention provide a high-temperature isothermal forging die material for aero-engines, comprising the following elements by mass percentage: C 0.06-0.17%, Cr 3.0-6.0%, Co 9.0-11.0%, W 14.0-17.0%, Mo 1.0-2.5%, Ta 2.5-4.0%, Nb 1.3-2.5%, Al 5.0-6.3%, Ti 1.1-1.7%, B 0.01-0.02%, Zr 0.03-0.08%, Re 0.20-0.75%, Mg 0.001-0.01%, Ce 0.001-0.01%, Y 0.001-0.01%, balance is Ni.

[0008] In some embodiments of the present invention, the following elements are included by mass percentage: C 0.11%, Cr 4.2%, Co 10.2%, W 15.6%, Mo 1.9%, Ta 3.1%, Nb 1.8%, Al 5.3%, Ti 1.5%, B 0.015%, Zr 0.04%, Re 0.25%, Mg 0.0015%, Ce 0.0015%, Y 0.0015%, balance Ni.

[0009] In some embodiments of the present invention, the percentage by mass includes the following elements: C 0.08%, Cr 5.8%, Co 9.8%, W 16%, Mo 2.5%, Ta 2.5%, Nb 2.1%, Al 6.0%, Ti 1.1%, B 0.01%, Zr 0.08%, Re 0.75%, Mg 0.001%, Ce 0.001%, Y 0.001%, balance Ni.

[0010] In some embodiments of the present invention, the elemental sources of the above-mentioned material raw materials include the following raw materials: Graphite, elemental chromium, elemental cobalt, elemental tungsten, elemental molybdenum, elemental tantalum, elemental niobium, elemental aluminum, elemental titanium, ferroboron, elemental zirconium, elemental rhenium, elemental nickel, NiMg alloy, NiCe alloy, NiY alloy.

[0011] On the other hand, embodiments of the present invention provide a method for preparing isothermal forging high-temperature die material for aero-engines, comprising: S1, clean the magnesium oxide crucible of the vacuum induction furnace, add the first raw material to the magnesium oxide crucible in batches, and heat it with a power of 200-800KW to clean it; S2, after the first raw material has been completely dissolved, keep it at 1550±10℃ for 10-20 minutes to refine the alloy; S3, reduce power to 150-280KW, cool for 75 minutes, stir, then reduce power to 0KW and cool for 35-50 minutes; S4. Add Ti-containing raw materials to the magnesium oxide crucible, increase the power to 300KW, keep it warm for 3 minutes, then add Al-containing raw materials, keep it warm for 5 minutes, stir for 8 minutes, then add B-containing raw materials, Zr-containing raw materials, NiMg, NiCe, and NiY, keep it warm for 5 minutes, stir for 8 minutes, then reduce the power to 0KW and cool down. S5. When the temperature drops to 1470±30℃, increase the power to 300-400KW, and at this power, pour the alloy liquid in the magnesium oxide crucible into the ingot mold. After cooling for 30 minutes, remove it from the furnace to obtain the material.

[0012] In some embodiments of the present invention, in step S1, the pressure inside the vacuum induction furnace during cleaning is ≤20Pa.

[0013] In some embodiments of the present invention, in step S2, the pressure inside the vacuum induction furnace is ≤10 Pa.

[0014] In some embodiments of the present invention, the first raw material is a raw material containing elements of C, Cr, Co, W, Mo, Ta, Nb, and Re.

[0015] In some embodiments of the present invention, in step S1, the first raw material is added to the magnesium oxide crucible in three batches. The first heating power after the first batch of raw material is added is 200-500KW; the second heating power after the second batch of raw material is added is 300-600KW; and the third heating power after the third batch of raw material is added is 400-800KW. The first heating power is less than the second heating power and the third heating power.

[0016] Compared with the prior art, the embodiments of the present invention have at least the following advantages or beneficial effects: The mold alloy material provided in this embodiment of the invention incorporates high-melting-point solid solution strengthening element Re, active element Mg, and rare earth elements Ce and Y, which further improves the strength and plasticity of the alloy at 1100℃ and extends the service life of isothermal forging dies.

[0017] In preparing the alloy material of the present invention, melting is carried out in a vacuum induction furnace. First, raw materials C, Cr, Co, W, Mo, Ta, Nb, and Re are added and refined at 1550±10℃. Then, the temperature is lowered and cooled. After cooling, the temperature is slowly raised and raw materials Ti, Al, B, Zr, NiMg, NiCe, and NiY are added in batches to further improve the strength and toughness of the alloy. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is the test report for the comparative alloy of this invention; Figure 2 This is the test report 1 for Embodiment 1 of the present invention; Figure 3 This is the test report 2 for Embodiment 1 of the present invention; Figure 4 This is the test report 1 for Embodiment 4 of the present invention; Figure 5 This is test report 2 for embodiment 4 of the present invention; Figure 6 This is the test report 1 for Embodiment 3 of the present invention; Figure 7 This is the test report 2 for Embodiment 3 of the present invention; Figure 8 This is the test report 3 for Embodiment 3 of the present invention. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0021] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to specific embodiments.

[0022] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0023] Example 1 Prepare the raw materials according to the following element ratios: C 0.11%, Cr 4.2%, Co 10.2%, W 15.6%, Mo 1.9%, Ta 3.1%, Nb 1.8%, Al 5.3%, Ti 1.5%, B 0.015%, Zr 0.04%, Re 0.25%, Mg 0.0015%, Ce 0.0015%, Y 0.0015%, balance Ni.

[0024] The alloy material of this embodiment was prepared according to the following method: S1. Clean the magnesium oxide crucible of the vacuum induction furnace. Add the first raw material to the magnesium oxide crucible in three batches. After the first batch of raw material is added, power is supplied and the heating power is adjusted to 300KW. After the second batch of raw material is added, the power is increased to 400KW. After the third batch of raw material is added, the power is increased to 500KW. The mixture is then completely melted into a liquid state. The pressure inside the vacuum induction furnace is ≤20Pa.

[0025] S2, after the first raw material has been completely purified, increase the power to 800KW, heat to 1550±10℃, hold for 20min, and refine the alloy; the pressure in the vacuum induction furnace is ≤20Pa.

[0026] S3, reduce power to 150KW, cool for 75 minutes, stir for 8 minutes, then reduce power to 0KW and stop power supply, cool for 50 minutes; the pressure inside the vacuum induction furnace is ≤10Pa.

[0027] S4, then alloying: Add Ti-containing raw materials to the magnesium oxide crucible, turn on the power and increase the power to 300KW, hold for 3 minutes, then add Al-containing raw materials, hold for 5 minutes, stir for 8 minutes, then wrap B-containing raw materials, Zr-containing raw materials, NiMg, NiCe, and NiY in aluminum foil, add them to the magnesium oxide crucible, hold for 5 minutes, stir for 8 minutes, then turn off the power and reduce the power to 0KW, and cool down; S5. When the temperature drops to 1470±30℃, increase the power to 300KW, and at this power, pour the molten alloy from the magnesium oxide crucible into the baked ingot mold. After cooling for 30 minutes, remove it from the furnace to obtain the material. Send the material to a third-party testing institution for testing; the test report is as follows... Figure 2-3 As shown.

[0028] Example 2 Prepare the raw materials according to the following element ratios: C 0.08%, Cr 5.8%, Co 9.8%, W 16%, Mo 2.5%, Ta 2.5%, Nb 2.1%, Al 6.0%, Ti 1.1%, B 0.01%, Zr 0.08%, Re 0.75%, Mg 0.001%, Ce 0.001%, Y 0.001%, balance Ni.

[0029] Its preparation method is the same as that of Example 1.

[0030] Example 3 Prepare the raw materials according to the following element ratios: C 0.11%, Cr 4.1%, Co 10.2%, W 12.1%, Mo 1.7%, Ta 4%, Nb 1.9%, Al 6.2%, Ti 1.3%, B 0.015%, Zr 0.06%, Mg 0.002%, Ce 0.002%, Y 0.001%, balance Ni.

[0031] The preparation method is the same as that in Example 1. The material was sent to a third-party testing institution for testing, and the test report for the alloy is as follows: Figure 6-8 As shown, it should be noted that because Mg, Ce, and Y are particularly reactive elements with high vapor pressures, they are basically not left after smelting, making them difficult to detect in analytical results.

[0032] Example 4 The difference from Example 1 is that in this example, the Re content is 0.5%, while the proportions of the remaining elements and the alloy preparation method are the same as in Example 1. The material was sent to a third-party testing institution for testing, and the test report is as follows: Figure 4-5 As shown.

[0033] Comparative Example The difference between this comparative example and Example 1 is that the elemental composition is different; it does not contain 0.25% Re. The proportions of the remaining elements and the alloy preparation method are the same as in Example 1. The material was sent to a third-party testing institution for testing, and the test report is as follows: Figure 1 As shown.

[0034] For the above embodiments and comparative examples, the raw materials of each element in their alloys are shown in Table 1.

[0035] Table 1 Raw Materials

[0036] Experimental Example For the alloy materials of Examples 1 and 4, and the comparative examples, a creep rupture test was conducted using the standard HB5150-1996. The test temperature was 1100℃ and the stress was 70 MPa. The results are shown in Table 1.

[0037] Table 1. Test results of each alloy

[0038] Table 1 shows that adding a certain amount of Re to the base alloy can improve the strength and toughness of the alloy at 1100℃.

[0039] In summary, the mold alloy material provided in this embodiment of the invention incorporates high-melting-point solid solution strengthening element Re, active element Mg, and rare earth elements Ce and Y, further improving the alloy's strength and plasticity at 1100℃ and extending the service life of isothermal forging dies. In preparing the alloy material of this invention, melting is carried out in a vacuum induction furnace. First, raw materials C, Cr, Co, W, Mo, Ta, Nb, and Re are added, and refining is performed at 1550±10℃. Then, the temperature is lowered and cooled, followed by a slow reheating, and raw materials Ti, Al, B, Zr, NiMg, NiCe, and NiY are added in stages to further improve the alloy's strength and toughness.

[0040] The embodiments described above are some, but not all, embodiments of the present invention. The detailed description of the embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. A high-temperature isothermal forging die material for aero-engines, characterized in that, Measured as a percentage by mass, including the following elements: C 0.06-0.17%, Cr 3.0-6.0%, Co 9.0-11.0%, W 14.0-17.0%, Mo 1.0-2.5%, Ta 2.5-4.0%, Nb 1.3-2.5%, Al 5.0-6.3%, Ti 1.1-1.7%, B 0.01-0.02%, Zr 0.03-0.08%, Re 0.20-0.75%, Mg 0.001-0.01%, Ce 0.001-0.01%, Y 0.001-0.01%, balance Ni.

2. The isothermal forging high-temperature die material for aero-engines according to claim 1, characterized in that, Measured as a percentage by mass, including the following elements: C 0.11%, Cr 4.2%, Co 10.2%, W 15.6%, Mo 1.9%, Ta 3.1%, Nb 1.8%, Al 5.3%, Ti 1.5%, B 0.015%, Zr 0.04%, Re 0.25%, Mg 0.0015%, Ce 0.0015%, Y 0.0015%, balance Ni.

3. The isothermal forging high-temperature die material for aero-engines according to claim 1, characterized in that, The percentage by mass includes the following elements: C 0.08%, Cr 5.8%, Co 9.8%, W 16.0%, Mo 2.5%, Ta 2.5%, Nb 2.1%, Al 6.0%, Ti 1.1%, B 0.01%, Zr 0.08%, Re 0.75%, Mg 0.001%, Ce 0.001%, Y 0.001%, balance Ni.

4. The isothermal forging high-temperature die material for aero-engines according to claim 1, characterized in that, Including the following raw materials: Graphite, elemental chromium, elemental cobalt, elemental tungsten, elemental molybdenum, elemental tantalum, elemental niobium, elemental aluminum, elemental titanium, ferroboron, elemental zirconium, elemental rhenium, elemental nickel, NiMg alloy, NiCe alloy, NiY alloy.

5. A method for preparing a high-temperature isothermal forging die material for aero-engines as described in any one of claims 1-4, characterized in that, Includes the following steps: S1, clean the magnesium oxide crucible of the vacuum induction furnace, add the first raw material to the magnesium oxide crucible in batches, and heat it with a power of 200-800KW to clean it; S2, after the first raw material has been completely dissolved, keep it at 1550±10℃ for 10-20 minutes to refine the alloy; S3, reduce power to 150-280KW, cool for 75 minutes, stir, then reduce power to 0KW and cool for 35-50 minutes; S4. Add Ti-containing raw materials to the magnesium oxide crucible, increase the power to 300KW, keep it warm for 3 minutes, then add Al-containing raw materials, keep it warm for 5 minutes, stir for 8 minutes, then add B-containing raw materials, Zr-containing raw materials, NiMg, NiCe, and NiY, keep it warm for 5 minutes, stir for 8 minutes, then reduce the power to 0KW and cool down. S5. When the temperature drops to 1470±30℃, increase the power to 300-400KW, and at this power, pour the alloy liquid in the magnesium oxide crucible into the ingot mold. After cooling for 30 minutes, remove it from the furnace to obtain the material.

6. The method for preparing high-temperature isothermal forging die material for aero-engines according to claim 5, characterized in that, In step S1, the pressure inside the vacuum induction furnace during cleaning is ≤20Pa.

7. The method for preparing high-temperature isothermal forging die material for aero-engines according to claim 5, characterized in that, In step S2, the pressure inside the vacuum induction furnace is ≤10Pa.

8. The method for preparing high-temperature isothermal forging die material for aero-engines according to claim 5, characterized in that, The first raw material is a raw material containing elements C, Cr, Co, W, Mo, Ta, Nb, and Re.

9. The method for preparing high-temperature isothermal forging die material for aero-engines according to claim 5, characterized in that, In step S1, the first raw material is added to the magnesium oxide crucible in three batches. The first heating power after the first batch of raw material is added is 200-500KW; the second heating power after the second batch of raw material is added is 300-600KW; and the third heating power after the third batch of raw material is added is 400-800KW. The first heating power is less than the second heating power and the third heating power.

Images