Heat treatment process for improving structure performance of 12Cr1MoV alloy structural steel

Abstract

The invention discloses a heat treatment process for improving the structure performance of 12Cr1MoV alloy structural steel, which comprises the following steps: normalizing: putting a sample into a heating furnace, heating to 920-950 DEG C, preserving heat for 120 minutes, then taking out the sample, and cooling in air; the 12Cr1MoV alloy structural steel comprises the following chemical components in percentage by mass: 0.08%-0.15% of C, 0.15%-0.30% of S i, 0.5%-0.6% of Mn, less than or equal to 0.025% of P, less than or equal to 0.010% of S, 0.9%-1.0% of Cr, 0.3%-0.4% of Mo, 0.27%-0.25% of V and the balance of Fe and impurities. According to the heat treatment technology for improving the structure performance of the 12Cr1MoV alloy structural steel, the 12Cr1MoV alloy structural steel has good comprehensive mechanical performance, the overall service life of the 12Cr1MoV alloy structural steel is remarkably prolonged, and the safety of the 12Cr1MoV alloy structural steel is remarkably improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of heat treatment processes for metal materials, and particularly relates to a heat treatment process for improving the microstructure and properties of 12Cr1MoV alloy structural steel. Background Art

[0002] Alloy structural steel is developed by adding a small amount of alloying elements on the basis of carbon steel, and the strength, toughness and processing performance of the steel are all improved. It is mainly used in industries such as construction, transportation, and machinery, with a large consumption and a wide range of applications. It can meet the requirements of various special properties and meet the requirements of technological process upgrading and product replacement. In 12Cr1MoV alloy structural steel, adding Cr element mainly plays the role of solid solution strengthening and improving corrosion resistance. Usually, Cr element is used in combination with Mo element, which can change the distribution of Mo element between carbides and solid solution, and strengthen ferrite; relying on the dispersion strengthening generated by carbides such as VC formed by the combination of V element and C element, the organizational structure has stability.

[0003] Heat treatment can adjust the internal microstructure of steel, making it have higher corrosion resistance during use. Through the heat treatment process, a uniform microstructure can be formed, reducing microdefects and the risk of stress corrosion cracking. It can enhance the strength and toughness of the steel, ensuring that it is not easy to break or deform during long-term use in the soil. This is crucial for maintaining the overall stability and safety of the structure. Summary of the Invention

[0004] The purpose of the present invention is to provide a heat treatment process for improving the microstructure and properties of 12Cr1MoV alloy structural steel, so that it has good comprehensive mechanical properties, and thus significantly improve the overall life and safety of 12Cr1MoV alloy structural steel.

[0005] To solve the above technical problems, the present invention adopts the following technical solutions:

[0006] A heat treatment process for improving the microstructure and properties of 12Cr1MoV alloy structural steel of the present invention includes: normalizing: putting the sample into a heating furnace, heating to 920 - 950 °C, holding for 120 min, then taking out the sample and cooling it in air;

[0007] The chemical composition of the 12Cr1MoV alloy structural steel by mass percentage includes: C 0.08 - 0.15%, Si 0.15 - 0.30%, Mn 0.5 - 0.6%, P ≤ 0.025%, S ≤ 0.010%, Cr 0.9 - 1.0%, Mo 0.3 - 0.4%, V 0.27 - 0.25%, and the balance is Fe and unavoidable impurities.

[0008] Furthermore, the chemical composition of the 12Cr1MoV alloy structural steel by mass percentage includes: C 0.12%, Si 0.22%, Mn 0.55%, P 0.018%, S 0.006%, Cr 0.99%, Mo 0.31%, V 0.22%, and the balance is Fe and unavoidable impurities.

[0009] Furthermore, the chemical composition of the 12Cr1MoV alloy structural steel by mass percentage includes: C 0.11%, Si 0.20%, Mn 0.54%, P 0.013%, S 0.004%, Cr 0.98%, Mo 0.30%, V 0.20%, and the balance is Fe and unavoidable impurities.

[0010] Furthermore, the chemical composition of the 12Cr1MoV alloy structural steel by mass percentage includes: C 0.10%, Si 0.19%, Mn 0.56%, P 0.014%, S 0.007%, Cr 0.95%, Mo 0.33%, V 0.19%, and the balance is Fe and unavoidable impurities.

[0011] Furthermore, it includes: normalizing: putting the rough - machined blank sample of 12Cr1MoV alloy structural steel into a heating furnace, heating it to 950 °C, holding for 120 min, and then cooling it in air.

[0012] Furthermore, it includes: putting the rough - machined blank sample of 12Cr1MoV alloy structural steel into a heating furnace, heating it to 940 °C, holding for 120 min, and then cooling it in air.

[0013] Furthermore, it includes: putting the rough - machined blank sample of 12Cr1MoV alloy structural steel into a heating furnace, heating it to 930 °C, holding for 120 min, and then cooling it in air.

[0014] Compared with the prior art, the beneficial technical effects of the present invention are:

[0015] On the premise of ensuring the structure and properties after heat treatment, the heating temperature range is narrowed, the holding time is reduced, the energy consumption of heat treatment is lowered, and the efficiency of heat treatment is improved. The strength and toughness of the 12Cr1MoV alloy structural steel after heat treatment are significantly improved. Specific embodiments

[0016] Example 1: The steel part of the heat treatment process of the present invention is 12Cr1MoV alloy structural steel, and it is carried out according to the following steps:

[0017] Normalizing: putting the rough - machined blank sample of 12Cr1MoV alloy structural steel into a heating furnace, heating it to 950 °C, holding for 120 min, and then cooling it in air.

[0018] Example 2: The steel part in the heat treatment process of the present invention is 12Cr1MoV alloy structural steel, and the steps are as follows:

[0019] Normalizing: Put the rough-machined blank sample of 12Cr1MoV alloy structural steel into a heating furnace, heat it up to 940 °C, hold for 120 min, and then cool it in the air.

[0020] Example 3: The steel part in the heat treatment process of the present invention is 12Cr1MoV alloy structural steel, and the steps are as follows:

[0021] Normalizing: Put the rough-machined blank sample of 12Cr1MoV alloy structural steel into a heating furnace, heat it up to 930 °C, hold for 120 min, and then cool it in the air.

[0022] After each example completes the heat treatment, the rough-machined blank sample is finish-machined, and various performance inspections are carried out. The chemical composition is shown in Table 1, and the inspection results are shown in Tables 2 and 3. It can be seen from Tables 1, 2 and 3 that all performance indicators are higher than the required indicators, and the performance of the specimen after heat treatment is qualified.

[0023] Table 1 Chemical composition of the test steel

[0024]

[0025]

[0026] Table 2 Mechanical properties at room temperature after heat treatment

[0027]

[0028] Table 3 Impact toughness at room temperature after heat treatment

[0029]

[0030] The above-described embodiments are only descriptions of the preferred embodiments of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention should fall within the protection scope determined by the claims of the present invention.

Claims

1. A heat treatment process for improving the microstructure and properties of 12Cr1 MoV alloy structural steel, characterized in that: include: Normalizing: Place the sample in a heating furnace, heat to 920-950°C, keep warm for 120 minutes, then take out the sample and cool it in the air; The chemical composition of the 12Cr1 MoV alloy structural steel includes, by mass percentage, C 0.08-0.15%, Si 0.15-0.30%, Mn 0.5-0.6%, P≤0.025%, S≤0.010%, Cr 0.9-1.0%, Mo 0.3-0.4%, V 0.27-0.25%, and the balance is Fe and unavoidable impurities.

2. The heat treatment process for improving the microstructure and properties of 12Cr1MoV alloy structural steel according to claim 1, characterized in that: The chemical composition of the 12Cr1 MoV alloy structural steel includes, by mass percentage, C 0.12%, Si 0.22%, Mn 0.55%, P 0.018%, S 0.006%, Cr 0.99%, Mo 0.31%, V 0.22%, and the remainder is Fe and unavoidable impurities.

3. The heat treatment process for improving the microstructure and properties of 12Cr1MoV alloy structural steel according to claim 1, characterized in that: The chemical composition of the 12Cr1 MoV alloy structural steel includes, by mass percentage, C 0.11%, Si 0.20%, Mn 0.54%, P 0.013%, S 0.004%, Cr 0.98%, Mo 0.30%, V 0.20%, and the balance is Fe and unavoidable impurities.

4. The heat treatment process for improving the microstructure and properties of 12Cr1MoV alloy structural steel according to claim 1, characterized in that: The chemical composition of the 12Cr1 MoV alloy structural steel includes, by mass percentage, C 0.10%, Si 0.19%, Mn 0.56%, P 0.014%, S 0.007%, Cr 0.95%, Mo 0.33%, V 0.19%, and the remainder is Fe and unavoidable impurities.

5. The heat treatment process for improving the microstructure and properties of 12Cr1MoV alloy structural steel according to claim 2, characterized in that: include: Normalizing: Place the rough-machined 12Cr1 MoV alloy structural steel blank sample into a heating furnace, heat it to 950℃, keep it warm for 120min, and then cool it in air.

6. The heat treatment process for improving the microstructure and properties of 12Cr1MoV alloy structural steel according to claim 3, characterized in that: include: The rough-machined 12Cr1 MoV alloy structural steel blank sample was placed in a heating furnace, heated to 940°C, kept warm for 120 minutes, and then cooled in air.

7. The heat treatment process for improving the microstructure and properties of 12Cr1MoV alloy structural steel according to claim 4, characterized in that: include: The rough-machined 12Cr1 MoV alloy structural steel blank sample was placed in a heating furnace, heated to 930°C, kept warm for 120 minutes, and then cooled in air.

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