High-strength ferro-nickel alloy and preparation method thereof

Abstract

The invention relates to the technical field of alloy materials, and provides a high-strength nickel-iron alloy and a preparation method thereof.The high-strength nickel-iron alloy is composed of, by mass, 25%-35% of Fe, 10%-15% of Cr, 1.3%-2.3% of Ti, 1.2%-1.8% of Co, 0.5%-2.5% of Al, 0.8%-1.2% of Mo, 0.3%-0.6% of Ge, 1%-1.5% of W, 0.02%-0.08% of Ta, 0.1%-0.5% of Si, 0.1%-0.3% of Ce, 0.01%-0.03% of C, 0.004%-0.006% of B and the balance Ni and inevitable impurities. According to the technical scheme, the problem that the strength of the ferro-nickel alloy in the related technology is low is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of alloy materials, and specifically, to a high-strength nickel-iron alloy and a preparation method thereof. Background Art

[0002] Nickel-iron-based alloys have been applied in many fields due to the cost advantage of iron and some properties of nickel, such as aerospace, automobile manufacturing, power equipment, etc. However, the problem of their low strength has been a concern. When the nickel content is within a specific range, although some properties of the alloy can be improved, such as corrosion resistance, magnetism, etc., its strength may be weakened. And if the content and distribution of other elements in the alloy are not properly controlled, it is easy to cause a decrease in the strength of the alloy. At the same time, for the process parameters in the production and processing process, such as melting temperature and time, casting cooling rate, hot working deformation amount and temperature, etc., if any link is not well controlled, it may cause defects inside the alloy, such as pores, shrinkage porosity, cracks, etc., seriously damaging the strength performance of the nickel-iron-based alloy.

[0003] Therefore, it is necessary to obtain a high-strength nickel-iron alloy to expand the application potential of nickel-iron alloys. Summary of the Invention

[0004] The present invention provides a high-strength nickel-iron alloy and a preparation method thereof, which solve the problem of low strength of nickel-iron alloys in the related art.

[0005] The technical solution of the present invention is as follows: The present invention provides a high-strength nickel-iron alloy, which is composed of the following components in mass percentage: Fe 25% - 35%, Cr 10% - 15%, Ti 1.3% - 2.3%, Co 1.2% - 1.8%, Al 0.5% - 2.5%, Mo 0.8% - 1.2%, Ge 0.3% - 0.6%, W 1% - 1.5%, Ta 0.02% - ٠.08%, Si 0.1% - 0.5%, Ce 0.1% - 0.3%, C 0.01% - 0.03%, B 0.004% - 0.006%, and the balance is Ni and unavoidable impurities.

[0006] As a further technical solution, it is composed of the following components in mass percentage: Fe 25% - 35%, Cr 10% - 15%, Ti 1.3% - 2.3%, Co 1.2% - 1.8%, Al 0.5% - 2.5%, Mo 0.8% - 1.2%, Ge 0.3% - 0.6%, W 1% - 1.5%, Ta 0.02% - 0.08%, Si 0.1% - 0.5%, Ce 0.1% - 0.3%, C 0.01% - 0.03%, B 0.004% - 0.006%, and the balance is Ni and unavoidable impurities, and 20.8% ≤ (Mo + Ge + W) / Ta ≤ 36%.

[0007] When these elements are combined in a specific proportional relationship of "20.8% ≤ Mo + Ge + W / Ta ≤ 36%", the strengthening effects among the elements can reach a better synergistic state. The strengthening effects of several elements are matched, making the movement of dislocations in the alloy more strongly hindered, thereby further improving the alloy strength.

[0008] The present invention also provides a method for preparing a high-strength nickel-iron alloy for preparing the high-strength nickel-iron alloy, comprising the following steps: S1. Weigh raw materials according to the components of the high-strength nickel-iron alloy, melt, cast, and hot-roll to obtain a billet; S2. Heat-treat the billet to obtain a nickel-iron alloy.

[0009] As a further technical solution, the temperature of the melting is 1450 - 1550 °C and the time is 2 - 3 h.

[0010] As a further technical solution, the temperature of the hot-rolling is 1000 - 1100 °C and the time is 15 - 25 min.

[0011] As a further technical solution, during the heat treatment, the temperature is raised at a heating rate of 25 - 30 °C / min to 1050 - 1090 °C, then held for 10 - 20 min, quenched for the first time, the temperature is raised at a heating rate of 12 - 16 °C / min to 800 - 900 °C, then held for 5 - 10 min, quenched for the second time, the temperature is raised at a heating rate of 5 - 10 °C / min to 480 - 560 °C, then held for 20 - 30 min, and cooled to room temperature.

[0012] In order to enable nickel-iron alloys to be used more durably in fields with severe wear such as machining and mining, and to reduce equipment replacement and maintenance caused by wear, the present invention adopts a unique three-stage heat treatment process to improve the wear resistance of nickel-iron alloys. First, it is heated to 1050 - 1090 °C at a heating rate of 25 - 30 °C / min and held for 10 - 20 min before the first quenching, so that carbides are fully and evenly dissolved in the austenite matrix, providing a good basis for subsequent microstructure transformation. At the same time, problems such as uneven microstructure transformation or insufficient carbide dissolution are avoided under this heating rate and holding time. Subsequently, it is heated to 800 - 900 °C at a heating rate of 12 - 16 °C / min, held for 5 - 10 min, and then the second quenching is carried out, which helps the austenite to fully transform into fine and uniform martensite. The high strength and hardness of martensite provide a good wear-resistant basis for the alloy. Finally, it is heated to 480 - 560 °C at a heating rate of 5 - 10 °C / min, held for 20 - 30 min, and during the process of cooling to room temperature, the quenching stress is effectively eliminated, and at the same time, fine and dispersed carbides are precipitated, further strengthening the alloy and enhancing its wear resistance. Through the heat treatment process of controlling the heating rate, temperature and holding time, the microstructure transformation inside the nickel-iron alloy is comprehensively and precisely regulated.

[0013] As a further technical solution, each of the first quenching and the second quenching independently includes one of water quenching and salt quenching.

[0014] As a further technical solution, the first quenching is salt quenching; the second quenching is water quenching.

[0015] As a further technical solution, the temperature of the first quenching is 180 - 200 °C and the time is 10 - 15 min.

[0016] The temperature of the second quenching is 150 - 350 °C and the time is 14 - 24 min.

[0017] During the heat treatment of nickel-iron alloys, salt quenching is adopted and the salt quenching temperature is controlled, which improves the wear resistance of nickel-iron alloys. After heat treatment, nickel-iron alloys exhibit lower wear loss. During the salt quenching process, the uniform and efficient heat transfer characteristics of the salt bath significantly improve the degree of microstructure homogenization of the alloy during the heating stage, avoiding performance unevenness caused by local overheating or insufficient heating. At the same time, through the precise control of the salt bath composition and temperature, it can promote the formation of a fine and stable microstructure in the alloy during the cooling stage, such as refining grains and optimizing the distribution of second-phase particles. These improvements in the microstructure greatly enhance the alloy's ability to resist wear.

[0018] As a further technical solution, the temperature of the first quenching is lower than the temperature of the second quenching.

[0019] The working principle and beneficial effects of the present invention are as follows: In the present invention, by sharing Mo 0.8% - 1.2%, Ge 0.3% - 0.6%, W 1% - 1.5%, and Ta 0.02% - 0.08% in a specific proportion, a significant improvement in the strength of nickel - iron alloy is achieved. Different from the prior art which only focuses on the effects of common elements or a single uncommon element on the strength improvement of nickel - iron alloy, the present invention adopts the synergistic strengthening mechanisms of several elements such as Mo, Ge, W, and Ta. Mo hinders dislocation movement through solid - solution strengthening and increasing the recrystallization temperature; Ge refines grains to increase the hindrance to dislocation movement; W generates lattice distortion due to its large atomic radius to improve strength; Ta forms a dispersion - strengthened phase to hinder dislocations. When these elements co - exist, the strengthening phases formed by Mo, W, and Ta are more evenly distributed due to the grain refinement by Ge, and the strengthening effects are superimposed. Compared with the prior art that only uses a single element for strengthening, this multi - element synergistic effect greatly improves the alloy strength, enabling the nickel - iron alloy to withstand greater loads in fields such as construction and mechanical manufacturing that require bearing large external forces, reducing problems such as deformation and damage caused by insufficient strength, and extending the service life. Specific Embodiments

[0020] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection of the present invention.

[0021] Embodiment 1 A high - strength nickel - iron alloy is composed of the following components by mass percentage: Fe 25%, Cr 10%, Ti 1.3%, Co 1.2%, Al 0.5%, Mo 0.8%, Ge 0.3%, W 1%, Ta 0.02%, Si 0.1%, Ce 0.1%, C 0.01%, B 0.004%, and the balance is Ni and inevitable impurities; A preparation method of the high - strength nickel - iron alloy includes the following steps: S1. Weigh the raw materials according to the components of the high - strength nickel - iron alloy, carry out smelting at 1450 °C for 3 h, cast, and hot - roll at 1000 °C for 25 min to obtain a billet; S2. Heat - treat the billet to obtain the nickel - iron alloy; during heat - treatment, heat it at a heating rate of 25 °C / min to 1050 °C, hold for 20 min, water - quench for 10 min, heat it at a heating rate of 12 °C / min to 800 °C, hold for 10 min, water - quench for 14 min, heat it at a heating rate of 5 °C / min to 480 °C, hold for 30 min, and then cool to room temperature.

[0022] Embodiment 2 High-strength nickel-iron alloy, consisting of the following components by mass percentage: Fe 35%, Cr 15%, Ti 2.3%, Co 1.8%, Al 2.5%, Mo 1.2%, Ge 0.6%, W 1.5%, Ta 0.08%, Si 0.5%, Ce 0.3%, C 0.03%, B 0.006%, the balance being Ni and unavoidable impurities; Preparation method of high-strength nickel-iron alloy, comprising the following steps: S1. Weigh raw materials according to the components of the high-strength nickel-iron alloy, melt them at 1550 °C for 2 h, cast them, and hot-roll them at 1000 °C for 15 min to obtain a billet; S2. Heat-treat the billet to obtain a nickel-iron alloy; during heat treatment, heat it up to 1090 °C at a heating rate of 30 °C / min, hold for 10 min, water-quench for 15 min, heat it up to 900 °C at a heating rate of 16 °C / min, hold for 5 min, water-quench for 24 min, heat it up to 560 °C at a heating rate of 10 °C / min, hold for 20 min, and cool to room temperature.

[0023] Example 3 High-strength nickel-iron alloy, consisting of the following components by mass percentage: Fe 28%, Cr 12.5%, Ti 1.9%, Co 1.65%, Al 1.2%, Mo 0.8%, Ge 0.3%, W 1%, Ta 0.02%, Si 0.3%, Ce 0.2%, C 0.02%, B 0.005%, the balance being Ni and unavoidable impurities; Preparation method of high-strength nickel-iron alloy, comprising the following steps: S1. Weigh raw materials according to the components of the high-strength nickel-iron alloy, melt them at 1500 °C for 2.5 h, cast them, and hot-roll them at 1050 °C for 20 min to obtain a billet; S2. Heat-treat the billet to obtain a nickel-iron alloy; during heat treatment, heat it up to 1060 °C at a heating rate of 25 °C / min, hold for 15 min, water-quench for 12 min, heat it up to 850 °C at a heating rate of 15 °C / min, hold for 8 min, water-quench for 20 min, heat it up to 510 °C at a heating rate of 6 °C / min, hold for 25 min, and cool to room temperature.

[0024] Example 4 The difference between this embodiment and Embodiment 3 lies only in the high-strength nickel-iron alloy, which is composed of the following components by mass percentage: Fe 28%, Cr 12.5%, Ti 1.9%, Co 1.65%, Al 1.2%, Mo 1.2%, Ge 0.6%, W 1.5%, Ta 0.08%, Si 0.3%, Ce 0.2%, C 0.02%, B 0.005%, and the balance is Ni and unavoidable impurities.

[0025] Embodiment 5 The difference between this embodiment and Embodiment 3 lies only in the high-strength nickel-iron alloy, which is composed of the following components by mass percentage: Fe 28%, Cr 12.5%, Ti 1.9%, Co 1.65%, Al 1.2%, Mo 0.9%, Ge 0.5%, W 1.4%, Ta 0.072%, Si 0.3%, Ce 0.2%, C 0.02%, B 0.005%, and the balance is Ni and unavoidable impurities.

[0026] Embodiment 6 The difference between this embodiment and Embodiment 3 lies only in the high-strength nickel-iron alloy, which is composed of the following components by mass percentage: Fe 28%, Cr 12.5%, Ti 1.9%, Co 1.65%, Al 1.2%, Mo 1%, Ge 0.6%, W 1.2%, Ta 0.035%, Si 0.3%, Ce 0.2%, C 0.02%, B 0.005%, and the balance is Ni and unavoidable impurities.

[0027] Embodiment 7 The difference between this embodiment and Embodiment 6 lies only in the heat treatment. After heating to 1060°C at a heating rate of 25°C / min, hold for 15 min, perform salt quenching at 200°C for 12 min, heat to 850°C at a heating rate of 15°C / min, hold for 8 min, perform water quenching for 20 min, heat to 510°C at a heating rate of 6°C / min, hold for 25 min, and then cool to room temperature.

[0028] Embodiment 8 The difference between this embodiment and Embodiment 6 lies only in the heat treatment. After heating to 1060°C at a heating rate of 25°C / min, hold for 15 min, perform salt quenching at 200°C for 12 min, heat to 850°C at a heating rate of 15°C / min, hold for 8 min, perform salt quenching at 200°C for 20 min, heat to 510°C at a heating rate of 6°C / min, hold for 25 min, and then cool to room temperature.

[0029] Embodiment 9 The difference between this example and Example 6 is only that during heat treatment, the temperature is raised to 1060°C at a heating rate of 25°C / min, then held for 15 minutes, salt quenched at 200°C for 12 minutes, the temperature is raised to 850°C at a heating rate of 15°C / min, then held for 8 minutes, salt quenched at 150°C for 20 minutes, the temperature is raised to 510°C at a heating rate of 6°C / min, then held for 25 minutes, and cooled to room temperature.

[0030] Example 10 The difference between this example and Example 6 is only that during heat treatment, the temperature is raised to 1060°C at a heating rate of 25°C / min, then held for 15 minutes, salt quenched at 200°C for 12 minutes, the temperature is raised to 850°C at a heating rate of 15°C / min, then held for 8 minutes, salt quenched at 350°C for 20 minutes, the temperature is raised to 510°C at a heating rate of 6°C / min, then held for 25 minutes, and cooled to room temperature.

[0031] Comparative Example 1 The difference between this comparative example and Example 3 is only that the high-strength nickel-iron alloy is composed of the following components by mass percentage: Fe 28%, Cr 12.5%, Ti 1.9%, Co 1.65%, Al 1.2%, Ge 0.3%, W 1%, Ta 0.02%, Si 0.3%, Ce 0.2%, C 0.02%, B 0.005%, and the balance is Ni and unavoidable impurities.

[0032] Comparative Example 2 The difference between this comparative example and Example 3 is only that the high-strength nickel-iron alloy is composed of the following components by mass percentage: Fe 28%, Cr 12.5%, Ti 1.9%, Co 1.65%, Al 1.2%, Mo 0.8%, W 1%, Ta 0.02%, Si 0.3%, Ce 0.2%, C 0.02%, B 0.005%, and the balance is Ni and unavoidable impurities.

[0033] Comparative Example 3 The difference between this comparative example and Example 3 is only that the high-strength nickel-iron alloy is composed of the following components by mass percentage: Fe 28%, Cr 12.5%, Ti 1.9%, Co 1.65%, Al 1.2%, Mo 0.8%, Ge 0.3%, Ta 0.02%, Si 0.3%, Ce 0.2%, C 0.02%, B 0.005%, and the balance is Ni and unavoidable impurities.

[0034] Experimental Example 1 The tensile strength of the nickel-iron alloys prepared in Examples 1 to 10 and Comparative Examples 1 to 3 was tested in accordance with the standard GB / T 228.1-2021 "Metallic materials - Tensile testing - Part 1: Method of test at room temperature", and the results are shown in Table 1 below.

[0035] Table 1 Performance test results

[0036] Compared with Comparative Examples 1 to 3, the nickel-iron alloys prepared in Examples 1 to 10 have higher tensile strength, indicating that the addition of Mo, W, Ta, and Ge in the components of the nickel-iron alloy significantly improves the strength of the nickel-iron alloy. [[ID=⑨]]

[0037] Experimental Example 2 The wear test of the nickel-iron alloys prepared in Examples 6 to 10 was carried out in accordance with the standard GB / T 12444-2006 "Metallic materials - Wear test methods - Ring-on-block sliding wear test", and the results are shown in Table 2 below.

[0038] Table 2 Performance test results

[0039] Compared with Examples 6 to 9, the nickel-iron alloy prepared in Example 10 has lower wear loss, indicating that the salt quenching and control of the salt quenching temperature during the heat treatment of the nickel-iron alloy improve the wear resistance of the nickel-iron alloy.

[0040] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A high-strength nickel-iron alloy, characterized in that, It consists of components with the following mass percentages: Fe 25% - 35%, Cr 10% - 15%, Ti 1.3% - 2.3%, Co 1.2% - 1.8%, Al 0.5% - 2.5%, Mo 0.8% - 1.2%, Ge 0.3% - 0.6%, W 1% - 1.5%, Ta 0.02% - 0.08%, Si 0.1% - 0.5%, Ce 0.1% - 0.3%, C 0.01% - 0.03%, B 0.004% - 0.006%, and the balance is Ni and unavoidable impurities.

2. A high-strength nickel-iron alloy according to claim 1, characterized in that, Fe 25% - 35%, Cr 10% - 15%, Ti 1.3% - 2.3%, Co 1.2% - 1.8%, Al 0.5% - 2.5%, Mo 0.8% - 1.2%, Ge 0.3% - 0.6%, W 1% - 1.5%, Ta 0.02% - 0.08%, Si 0.1% - 0.5%, Ce 0.1% - 0.3%, C 0.01% - 0.03%, B 0.004% - 0.006%, and the balance is Ni and unavoidable impurities, and 20.8% ≤ (Mo + Ge + W) / Ta ≤ 36%.

3. A method for preparing a high-strength nickel-iron alloy, which is used to prepare a high-strength nickel-iron alloy according to any one of claims 1 to 2, characterized in that, It includes the following steps: S1. Weigh raw materials according to the components of the high-strength nickel-iron alloy for melting, casting, and hot rolling to obtain a billet. S2. Heat-treat the billet to obtain a nickel-iron alloy.

4. The preparation method of a high-strength nickel-iron alloy according to claim 3, characterized in that The temperature of the melting is 1450 - 1550 °C, and the time is 2 - 3 h.

5. The preparation method of a high-strength nickel-iron alloy according to claim 3, characterized in that, The temperature of the hot rolling is 1000 - 1100 °C, and the time is 15 - 25 min.

6. The preparation method of a high-strength nickel-iron alloy according to claim 3, characterized in that, During the heat treatment, it is heated at a heating rate of 25 - 30 °C / min to 1050 - 1090 °C, then held for 10 - 20 min, followed by the first quenching. Then it is heated at a heating rate of 12 - 16 °C / min to 800 - 900 °C, held for 5 - 10 min, followed by the second quenching. Then it is heated at a heating rate of 5 - 10 °C / min to 480 - 560 °C, held for 20 - 30 min, and then cooled to room temperature.

7. The preparation method of a high-strength nickel-iron alloy according to claim 6, characterized in that, Each of the first quenching and the second quenching independently includes one of water quenching and salt quenching.

8. The preparation method of a high-strength nickel-iron alloy according to claim 6, characterized in that, The first quenching is salt quenching; the second quenching is water quenching.

9. The preparation method of a high-strength nickel-iron alloy according to claim 6, characterized in that, The temperature of the first quenching is 180 - 200 °C, and the time is 10 - 15 min. The temperature of the second quenching is 150 - 350 °C, and the time is 14 - 24 min.

10. The preparation method of a high-strength nickel-iron alloy according to claim 9, characterized in that, The temperature of the first quenching is lower than that of the second quenching.

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