Efficient heat treatment process based on 625 alloy plate

Abstract

The invention discloses an efficient heat treatment process based on a 625 alloy plate. The efficient heat treatment process comprises the steps that S1, degreasing is conducted, specifically, the 625 alloy plate obtained after cold rolling is subjected to degreasing cleaning through a chemical alkali washing method; s2, cleaning is conducted, specifically, the degreasing cleaning agent left on the surface of the 625 alloy plate is cleaned and dried; s3, continuous annealing is conducted, specifically, the degreased and cleaned 625 alloy plate is fed into a vacuum continuous annealing furnace to be subjected to heat treatment, and the temperature of the first area is 1000-1070 DEG C, the temperature of the second area is 1100-1130 DEG C, the temperature of the third area is 1100-1150 DEG C, the temperature of the fourth area is 1100-1150 DEG C, the temperature of the fifth area is 1100-1150 DEG C, and the temperature of the sixth area is 1100-1140 DEG C; and S4, cooling is conducted, specifically, the annealed 625 alloy plate is fed into a cooling section, and rapid cooling is conducted in an air cooling mode. Compared with the prior art, the problem that the grain size of the 625 nickel-based alloy plate does not meet the use requirement after the 625 nickel-based alloy plate is subjected to an existing heat treatment process is solved.

Description

Technical Field

[0001] The invention relates to the technical field of heat treatment, and in particular to an efficient heat treatment process based on a 625 alloy plate. Background Art

[0002] 625 nickel-based alloy has excellent corrosion resistance and oxidation resistance, good tensile properties and fatigue resistance between -196℃ and 980℃, and is widely used in aviation engine parts, aerospace structural components, chemical equipment, etc.

[0003] 625 alloy material is widely used in nuclear power high temperature reactors due to its excellent high temperature and corrosion resistance. However, the domestic production process of 625 alloy material is immature and the quality of heat treatment process is not high, resulting in the grain size of 625 alloy plate not meeting the use requirements when the material is used in nuclear power. Summary of the invention

[0004] The purpose of the present invention is to provide an efficient heat treatment process based on 625 alloy plate to solve the problem that the grain size of 625 nickel-based alloy plate does not meet the use requirements after the existing heat treatment process.

[0005] In order to achieve the above object, the present invention adopts the following technical solution: an efficient heat treatment process based on 625 alloy plate, comprising the following steps:

[0006] S1. Degreasing: The cold-rolled 625 alloy plate is degreased and cleaned by chemical alkali washing method;

[0007] S2. Cleaning: clean the degreasing cleaning agent remaining on the surface of the 625 alloy plate and dry it;

[0008] S3, continuous annealing: send the degreased and cleaned 625 alloy plate into a vacuum continuous annealing furnace for heat treatment, first evacuate the annealing furnace to a vacuum degree of 50-80Pa, and then backfill with pure hydrogen. During the heat treatment of the 625 alloy plate, the temperature of each zone is: zone 1 1000-1070°C, zone 2 1100-1130°C, zone 3 1100-1150°C, zone 4 1100-1150°C, zone 5 1100-1150°C, zone 6 1100-1140°C, and the annealing speed of the 625 alloy plate in the vacuum continuous annealing furnace is 7-10m / min;

[0009] S4. Cooling: The annealed 625 alloy plate is sent to the cooling section and quickly cooled by air cooling.

[0010] As a further description of the above technical solution:

[0011] In step S3, the annealing speed of the 625 alloy sheet with a thickness of 0.35 mm is 7.2 m / min, and the annealing speed of the 625 alloy sheet with a thickness of 0.15 mm is 10 m / min.

[0012] As a further description of the above technical solution:

[0013] In step S3, the annealing furnace is evacuated to a vacuum degree of 50-80 Pa and then backfilled with pure hydrogen, which is repeated multiple times.

[0014] As a further description of the above technical solution:

[0015] The degreasing cleaning agent is a NaOH solution with a mass fraction of 40%.

[0016] In step S1, the NaOH solution used as a degreasing cleaning agent is heated to 70-80°C, and then the 625 alloy plate is degreased and cleaned.

[0017] As a further description of the above technical solution:

[0018] In step S4, the cooling medium in the cooling section is nitrogen, and the cooling rate is 4-10°C / s.

[0019] As a further description of the above technical solution:

[0020] In step S4, the 625 alloy plate is first cooled to 400°C-500°C at 10°C / s in the cooling section, and then cooled to 80°C at 4°C / s before being taken out of the furnace.

[0021] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0022] 1. In the present invention, the 625 alloy plate is continuously annealed in a high temperature heat treatment furnace, and pure hydrogen is used for annealing during the heat treatment process to ensure that the surface of the material is uniformly bright. The finished 625 alloy plate after heat treatment meets the performance requirements of the American standard ASTMB443Gr2, and the grain size meets the 5-7 level.

[0023] 2. In the present invention, in the vacuum continuous annealing furnace, the temperature of the 625 alloy plate is gradually increased from the first zone, the second zone, and the third zone, the temperature of the fourth zone and the fifth zone is kept constant, and the annealing temperature is reduced in the sixth zone, thereby improving the comprehensive mechanical properties of the finished 625 alloy plate and the grain size grade. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 This is a flow chart of an efficient heat treatment process based on 625 alloy plate. DETAILED DESCRIPTION

[0026] In order to make the purpose, 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 in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0027] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Example 1

[0029] See also Figure 1 The present invention provides a technical solution: an efficient heat treatment process based on 625 alloy plate, comprising the following steps:

[0030] S1. Degreasing: The cold-rolled 625 alloy plate is degreased and cleaned by chemical alkali washing method;

[0031] S2. Cleaning: clean the degreasing cleaning agent remaining on the surface of the 625 alloy plate and dry it;

[0032] S3, continuous annealing: send the degreased and cleaned 625 alloy plate into a vacuum continuous annealing furnace for heat treatment, first evacuate the annealing furnace to a vacuum degree of 50-80Pa, and then backfill with pure hydrogen. During the heat treatment of the 625 alloy plate, the temperature of each zone is: zone 1 1000-1070°C, zone 2 1100-1130°C, zone 3 1100-1150°C, zone 4 1100-1150°C, zone 5 1100-1150°C, zone 6 1100-1140°C, and the annealing speed of the 625 alloy plate in the vacuum continuous annealing furnace is 7-10m / min;

[0033] S4. Cooling: The annealed 625 alloy plate is sent to the cooling section and quickly cooled by air cooling.

[0034] In step S3, the annealing speed of the 625 alloy sheet with a thickness of 0.35 mm is 7.2 m / min, and the annealing speed of the 625 alloy sheet with a thickness of 0.15 mm is 10 m / min. The annealing speeds of 625 alloy sheets of different thicknesses are different, which can not only effectively ensure the annealing quality, but also effectively improve the annealing efficiency.

[0035] Working principle: 625 alloy plate is continuously annealed in a high-temperature heat treatment furnace, and pure hydrogen is used for annealing during the heat treatment process to ensure that the surface of the material is bright and uniform. The finished 625 alloy plate after heat treatment meets the performance requirements of the American standard ASTMB443Gr2, and the grain size meets the 5-7 level. In the vacuum continuous annealing furnace, the 625 alloy plate is gradually heated from the first zone, the second zone, and the third zone, and the temperature in the fourth zone and the fifth zone is kept constant. The annealing temperature is reduced in the sixth zone to improve the comprehensive mechanical properties of the finished 625 alloy plate and improve the grain size grade.

[0036] Example 2

[0037] This embodiment further provides the following improved technical solutions based on the above embodiment: in step S3, the step of evacuating the annealing furnace to a vacuum degree of 50-80Pa and then backfilling with pure hydrogen is repeated multiple times. If the above steps are repeated 3 times, the purity of the pure hydrogen in the annealing furnace is effectively guaranteed, the annealing quality is guaranteed, and the surface brightness of the material is ensured to be uniform.

[0038] Example 3

[0039] This embodiment further provides the following improved technical solution based on the above embodiment: the degreasing cleaning agent is a NaOH solution with a mass fraction of 40%, which effectively realizes the degreasing cleaning of the 625 alloy plate and ensures the degreasing effect.

[0040] In addition, in step S1, the NaOH solution used as a degreasing cleaning agent is heated to 70-80°C before degreasing the 625 alloy plate. Heating the grease attached to the surface of the 625 alloy plate increases the reaction speed, effectively improving the cleaning effect and speed.

[0041] Example 4

[0042] This embodiment further provides the following improved technical solutions based on the above embodiments: in step S4, the cooling medium in the cooling section is nitrogen, the cooling rate is 4-10°C / s, and the cooling rate of the 625 alloy plate is controlled to ensure that the grain size meets the requirements.

[0043] Specifically, in step S4, the 625 alloy sheet is first cooled to 400-500°C at 10°C / s in the cooling section, and then cooled to 80°C at 4°C / s before being taken out of the furnace. The annealed 625 alloy sheet is first controlled to be rapidly cooled to 400-500°C, and then slowly cooled to 80°C, so as to effectively control the grain size of the 625 alloy sheet and ensure that the grain size reaches level 5-7.

[0044] Example 5

[0045] This embodiment further provides the following improved technical solutions based on the above embodiments: In step S2, the residual degreasing cleaning agent on the surface of the 625 alloy plate is cleaned by ultrasonic cleaning to effectively eliminate the residual degreasing cleaning agent.

[0046] Example 6

[0047] This embodiment further provides the following improved technical solutions based on the above embodiment: In step S2, the cleaning liquid is sprayed onto the surface of the 625 alloy plate at a pressure of 3.0 to 3.6 bar to clean the surface of the 625 alloy plate. The cleaning liquid can be deionized water, and the high-pressure spraying method can effectively improve the removal effect of the residual degreasing cleaning agent.

[0048] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An efficient heat treatment process based on 625 alloy plate, characterized in that: The following steps are involved: S1. Degreasing: The cold-rolled 625 alloy plate is degreased and cleaned by chemical alkali washing method; S2. Cleaning: clean the degreasing cleaning agent remaining on the surface of the 625 alloy plate and dry it; S3, continuous annealing: send the degreased and cleaned 625 alloy plate into a vacuum continuous annealing furnace for heat treatment, first evacuate the annealing furnace to a vacuum degree of 50-80Pa, and then backfill with pure hydrogen. During the heat treatment of the 625 alloy plate, the temperature of each zone is: zone 1 1000-1070°C, zone 2 1100-1130°C, zone 3 1100-1150°C, zone 4 1100-1150°C, zone 5 1100-1150°C, zone 6 1100-1140°C, and the annealing speed of the 625 alloy plate in the vacuum continuous annealing furnace is 7-10m / min; S4. Cooling: The annealed 625 alloy plate is sent to the cooling section and quickly cooled by air cooling.

2. The high-efficiency heat treatment process based on 625 alloy plate according to claim 1 is characterized in that: In step S3, the annealing speed of the 625 alloy sheet with a thickness of 0.35 mm is 7.2 m / min, and the annealing speed of the 625 alloy sheet with a thickness of 0.15 mm is 10 m / min.

3. The high-efficiency heat treatment process based on 625 alloy plate according to claim 1 is characterized in that: In step S3, the step of evacuating the annealing furnace to a vacuum degree of 50-80 Pa and then backfilling with pure hydrogen is repeated multiple times.

4. The high-efficiency heat treatment process based on 625 alloy plate according to claim 1 is characterized in that: The degreasing cleaning agent is a NaOH solution with a mass fraction of 40%.

5. The high-efficiency heat treatment process based on 625 alloy plate according to claim 4 is characterized in that: In the step S1, the NaOH solution used as a degreasing cleaning agent is heated to 70-80°C, and then the 625 alloy plate is degreased and cleaned.

6. The high-efficiency heat treatment process based on 625 alloy plate according to claim 1 is characterized in that: In step S4, the cooling medium in the cooling section is nitrogen, and the cooling rate is 4-10°C / s.

7. The high-efficiency heat treatment process based on 625 alloy plate according to claim 6 is characterized in that: In the step S4, the 625 alloy plate is first cooled to 400°C-500°C at 10°C / s in the cooling section, and then cooled to 80°C at 4°C / s before being taken out of the furnace.

8. The high-efficiency heat treatment process based on 625 alloy plate according to claim 1 is characterized in that: In the step S2, the degreasing cleaning agent remaining on the surface of the 625 alloy plate is cleaned by ultrasonic cleaning.

9. The high-efficiency heat treatment process based on 625 alloy plate according to claim 1, characterized in that: In the step S2, the cleaning liquid is sprayed onto the surface of the 625 alloy plate at a pressure of 3.0 to 3.6 bar to clean the surface of the 625 alloy plate.

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