Method for preparing iron-chromium-aluminum foil material

Abstract

The invention provides a method for preparing an iron-chromium-aluminum foil material. The method comprises the following steps: carrying out acid pickling, descaling and softening heat treatment on an iron-chromium-aluminum base material to obtain an iron-chromium-aluminum coiled material to be rolled; carrying out homogenization heat treatment on the to-be-rolled iron-chromium-aluminum coiled material, and carrying out primary rolling to obtain a semi-finished iron-chromium-aluminum coiled strip; performing cold finish rolling and stress relief annealing on the semi-finished iron-chromium-aluminum coil strip to obtain a finished iron-chromium-aluminum foil material; and performing special configuration on parameter design of a second intermediate roller and a first intermediate double-cone roller for primary rolling and cold finish rolling. According to the method, softening heat treatment can be carried out on base materials with the width being 1.0 mm or above and 600 mm or above, the technical bottleneck that the thickness and the width of the iron-chromium-aluminum foil are compatible is solved, the prepared foil is high in size precision and excellent and stable in structure performance, the production efficiency is improved, and the method is environmentally friendly and lower in carbon.

Description

Technical Field

[0001] The present invention belongs to the field of metal materials and relates to a method for preparing iron-chromium-aluminum foil. Background Art

[0002] Iron-chromium-aluminum foil is a special alloy material with excellent properties, such as high temperature resistance, oxidation resistance, corrosion resistance, high strength, good ductility, low thermal expansion coefficient, and good electrical and thermal conductivity. At temperatures above 1200 °C, it can still remain stable, not easily deformed or damaged. The stable oxide film formed on its surface effectively prevents further oxidation, significantly extending the service life of the material in high-temperature environments; the low thermal expansion coefficient ensures the dimensional stability of the material at high temperatures, making it suitable for precision instruments and equipment.

[0003] With the rapid development and popularization of application fields such as aerospace, new energy, automotive manufacturing, and the electronics industry in China, there is an urgent need for domestic high-quality ultra-thin wide-width iron-chromium-aluminum foil products with a thickness of 0.02 - 0.06 mm and a width of more than 600 mm. For example, in the aerospace field, its high temperature resistance and corrosion resistance are used to manufacture aircraft engine components, combustion chamber linings, thermal protection systems, etc., ensuring the reliability and safety of aircraft. Industrial heating equipment such as heating elements and resistance materials in industrial furnaces benefit from the high temperature tolerance of iron-chromium-aluminum foil, reducing maintenance frequency and improving equipment efficiency. In automotive exhaust treatment, it is used as a catalytic converter carrier, which not only has high temperature resistance and corrosion resistance but also improves exhaust treatment efficiency and the service life of vehicles. For heating elements in household appliances such as rice cookers and electric kettles, due to the good thermal conductivity and high temperature resistance of iron-chromium-aluminum foil, the efficiency and durability of the appliances are improved. In the electronics industry, as heat sinks and thermal shielding materials, its low thermal expansion coefficient and good thermal conductivity significantly improve the performance and reliability of electronic products.

[0004] Cold rolling is the key core technology for preparing ultra-thin wide-width iron-chromium-aluminum foil. However, during the rolling process, problems such as work hardening, thickness and tolerance accuracy, surface defects, and uneven distribution of microstructure and stress will be faced. Moreover, conventional rolling results in too many processing passes and intermediate annealing times, increasing production costs and reducing production efficiency. How to effectively solve the shape consistency and thickness uniformity of ultra-thin wide-width foil, and break through the technical bottleneck of the compatibility of the thinness and width of iron-chromium-aluminum foil

[0005] In summary, based on the current research on the technical process methods for preparing ultra-thin wide-width electrothermal alloy iron-chromium-aluminum foil being blank, and the preparation of ultra-thin wide-width iron-chromium-aluminum foil is restricted by both process equipment and technical processes, and it is difficult to be compatible with width and thinness. Summary of the Invention

[0006] The process research on the preparation technology of ultra-thin wide-width iron-chromium-aluminum foil is blank. The present invention proposes a new process route of stepped deformation integration technology to prepare ultra-thin wide-width micron-level iron-chromium-aluminum foil by maintaining stepped deformation integration.

[0007] The principle of the present invention is as follows: The 1.0 mm thick substrate is subjected to softening heat treatment to further optimize the structure and properties of the material itself, reduce performance parameters such as the hardness of the material. By virtue of the high stiffness advantage of the 20-high Sendzimir mill and the material characteristics of large rollable deformation resistance, a preparation process of maintaining stepped deformation integration is adopted, the rolling schedule and the amount of deformation are reasonably designed, the ability of the rolling process to cause tissue damage is weakened, and the cumbersome long-sequence preparation process flow of rolling is solved. Only two cold rolling schedules can produce the final foil specifications. Moreover, by studying the coupling relationship between the roll profiles of the first intermediate roll and the second intermediate roll and the roll system configuration, the surface depth of the upper and lower idler rolls and the taper length and taper of the first intermediate roll are increased and refined, realizing the flexible matching between the differential and refined configuration of the rolls, the substrate and the roughness.

[0008] To achieve the above object, the present invention proposes a method for preparing iron-chromium-aluminum foil, including:

[0009] S1: Pickle, descale and soften heat-treat the iron-chromium-aluminum substrate to obtain the to-be-rolled iron-chromium-aluminum coil;

[0010] S2: Conduct primary rolling and homogenization heat treatment on the to-be-rolled iron-chromium-aluminum coil to obtain a semi-finished iron-chromium-aluminum coil strip;

[0011] S3: Conduct cold finish rolling and stress relief annealing on the semi-finished iron-chromium-aluminum coil strip to obtain the finished iron-chromium-aluminum foil,

[0012] characterized in that

[0013] In the primary rolling, the configuration of the second intermediate roll is as follows: the upper and lower idler rolls are concave rolls, the surface depth is 0.1 mm, and the lubricant oil temperature is 40 - 45 °C; the configuration of the first intermediate double-cone roll is as follows: the taper length at both ends is 50 - 150 mm, the height difference on both sides of the taper length area is 0.07 - 0.1 mm, the roughness value is greater than 0.4 Ra, and the thickness of the obtained semi-finished iron-chromium-aluminum coil strip is less than 0.1 mm;

[0014] In the cold finish rolling, the configuration of the second intermediate roll system is as follows: the upper and lower idler rolls are concave rolls, the surface depth is 0.05 mm, and the lubricant oil temperature is 35 - 40 °C; the configuration of the first intermediate double-cone roll is as follows: the taper length at both ends is 30 - 70 mm, the height difference on both sides of the taper length area is 0.06 - 0.1 mm, the roughness value is 0.13 - 0.3 Ra, and the thickness of the obtained finished iron-chromium-aluminum foil is less than 0.02 mm and the width is greater than 600 mm.

[0015] It should be noted that the specifications of the FeCrAl substrate before rolling are set to a thickness greater than 1.0 mm and a width greater than 600 mm. At the same time, the heat treatment process parameters are pre-set before rolling to obtain the technical requirements for the required rolling process conditions.

[0016] According to an embodiment of the present invention, the annealing temperature of the softening heat treatment is 950 - 1200 °C, the heating rate is 10 - 20 °C / s, the cooling method is furnace cooling, and finally a FeCrAl coil with a uniform surface and good tissue properties is obtained.

[0017] According to an embodiment of the present invention, the total deformation amount of the first rolling is 90 - 95%, the processing rate of the first pass is controlled at 5 - 8%, the processing rate of each subsequent pass is controlled at 17 - 32%, and the processing rate of the last pass is controlled at 4 - 8%.

[0018] According to an embodiment of the present invention, the unit tensions at the rolling inlet and outlet of the first rolling are controlled at 100.0 - 510.0 N / mm 2 (±30), the total rolling force is 100.0 - 150.0 T, and the rolling speed is 90.0 - 200.0 m / min.

[0019] According to an embodiment of the present invention, the annealing temperature of the homogenization heat treatment is 910 - 1050 °C, and the heating rate is 18 - 25 °C / s.

[0020] According to an embodiment of the present invention, the total rolling deformation amount of the cold finish rolling is 70 - 80%, the processing rate of the first pass is controlled at 3 - 5%, the processing rate of each subsequent pass is controlled at 10 - 20%, and the processing rate of the last pass is controlled at 5 - 7%.

[0021] It should be noted that the cold-rolled material uses M2 and M42 high-hardness work rolls, and the air pressure is controlled between 3 - 4 KG.

[0022] According to an embodiment of the present invention, the difference in unit tensions at the rolling inlet and outlet of the cold finish rolling is 200 - 420 N / mm 2 (±30), the total rolling force is 70.0 - 200.0 T, and the rolling speed is 200.0 - 400.0 m / min.

[0023] Invention Effect

[0024] 1. The new step-shaped integrated technology process path proposed in the present invention provides a better process guidance and technical support for the preparation method of ultra-thin wide-width iron-chromium-aluminum foil; and, through the preparation process described in the present invention, the plate size accuracy and mechanical properties of the foil are accurately controlled, the lattice arrangement of the material is more orderly, and the tissue distribution is more uniform, so that it can adapt to a variety of high-precision application environments, fundamentally solving the long-span cold rolling process between the substrate plate and the finished foil, and breaking through the preparation problem of plate shape consistency and thickness uniformity of ultra-thin wide-width iron-chromium-aluminum foil that is compatible with the thickness and width.

[0025] 2. The step deformation integrated preparation process path described in the present invention is to achieve a more precise shape and performance integration process by controlling the degree of deformation in different rolling stages; step deformation can help avoid excessive deformation or damage of the material during the processing process, and ensure the uniformity and consistency of the foil plate shape.

[0026] 3. The present invention prepares the final foil specifications through only two cold rolling procedures, significantly improving the size and shape accuracy, apparent quality and yield rate of ultra-thin wide-width iron-chromium-aluminum foil, and reducing its production cost.

[0027] 4. The present invention improves the uniform deformation of metal flow during rolling by designing the coupling relationship between the roll type and the roll system configuration, reduces the relative sliding and surface defects between the rolls and the strip, and improves the rolling efficiency and the plate quality of the product. Specific embodiments

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. The following description of at least one exemplary embodiment is actually only illustrative and is by no means a limitation on the present invention and its application or use. Based on the embodiments in 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. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic flow chart of the method for preparing iron-chromium-aluminum foil of the present invention.

[0030] Example 1

[0031] This embodiment uses an iron-chromium-aluminum substrate with a thickness of 1.0 mm and a width of 700 mm.

[0032] S1: Roll using a 20-high Sendzimir rolling mill, and subject the FeCrAl substrate to pickling, descaling, and softening heat treatment to obtain the FeCrAl coil to be rolled. The relevant process parameters are as follows.

[0033] S2: Conduct primary rolling and homogenizing heat treatment on the FeCrAl coil to be rolled to obtain a semi-finished FeCrAl strip. The configuration parameters for primary rolling are as follows.

[0034]

[0035] Among them, the primary rolling schedule is as follows.

[0036]

[0037] S3: Conduct cold finish rolling and stress annealing on the semi-finished FeCrAl strip to obtain a finished FeCrAl foil. The configuration parameters for cold finish rolling are as follows.

[0038]

[0039]

[0040] Among them, the cold finish rolling schedule is as follows.

[0041]

[0042] The finally obtained finished FeCrAl foil has a thickness of 0.015 mm and a width of 650 mm.

[0043] Example 2

[0044] In this example, an FeCrAl substrate with a thickness of 1.5 mm and a width of 750 mm is used.

[0045] S1: Roll using a 20-high Sendzimir rolling mill, and subject the FeCrAl substrate to pickling, descaling, and softening heat treatment to obtain the FeCrAl coil to be rolled. The relevant process parameters are as follows.

[0046] S2: Conduct primary rolling and homogenizing heat treatment on the FeCrAl coil to be rolled to obtain a semi-finished FeCrAl strip. The configuration parameters for primary rolling are as follows.

[0047]

[0048]

[0049] Among them, the primary rolling schedule is as follows.

[0050]

[0051] S3: Conduct cold finish rolling and stress annealing on the semi-finished FeCrAl strip to obtain a finished FeCrAl foil.

[0052]

[0053] Among them, the cold finishing rolling schedule is as follows.

[0054]

[0055]

[0056] The finally obtained finished iron-chromium-aluminum foil has a thickness of 0.018 mm and a width of 650 mm.

[0057] Example 3

[0058] This example uses an iron-chromium-aluminum base material with a thickness of 1.8 mm and a width of 750 mm.

[0059] S1: Use a 20-high Sendzimir mill for rolling. Pickle, dephosphorize, and perform softening heat treatment on the iron-chromium-aluminum base material to obtain the iron-chromium-aluminum coil to be rolled. The relevant process parameters are as follows.

[0060] S2: Perform primary rolling and homogenization heat treatment on the iron-chromium-aluminum coil to be rolled to obtain a semi-finished iron-chromium-aluminum strip. The configuration parameters of the primary rolling are as follows.

[0061]

[0062] Among them, the primary rolling schedule is as follows.

[0063]

[0064] S3: Perform cold finishing rolling and stress annealing on the semi-finished iron-chromium-aluminum strip to obtain a finished iron-chromium-aluminum foil. The configuration parameters of the cold finishing rolling are as follows.

[0065]

[0066] Among them, the cold finishing rolling schedule is as follows.

[0067]

[0068] The finally obtained finished iron-chromium-aluminum foil has a thickness of 0.016 mm and a width of 680 mm.

[0069] It should be noted that the above examples are only used to illustrate the technical solutions of the present invention rather than to limit them; although the present invention has been described in detail with reference to the examples, those of ordinary skill in the art should understand that any modification or equivalent replacement of the technical solutions of the present invention does not depart from the spirit and scope of the technical solutions of the present invention, and they should all be covered by the scope of the claims of the present invention.

Claims

1. A method for preparing an iron-chromium-aluminum foil, comprising: S1: pickling, descaling and softening heat treatment of the iron-chromium-aluminum substrate to obtain the iron-chromium-aluminum coil to be rolled; S2: performing primary rolling and homogenization heat treatment on the iron-chromium-aluminum coil to be rolled to obtain a semi-finished iron-chromium-aluminum coil; S3: cold finishing rolling and stress annealing are performed on the semi-finished iron-chromium-aluminum coil to obtain a finished iron-chromium-aluminum foil. It is characterized in that In the cold finishing rolling, the two intermediate rollers are configured as follows: the upper and lower idler rollers are concave rollers, the curved surface depth is 0.05 mm, and the lubricant oil temperature is 35-40°C; the configuration of an intermediate double-cone roller is as follows: the cone lengths at both ends are 30-70 mm, the height difference on both sides of the cone length area is 0.06-0.1 mm, and the roughness value is 0.13-0.3Ra. The thickness of the finished iron-chromium-aluminum foil obtained is less than 0.02 mm and the width is greater than 600 mm.

2. The method for preparing the iron-chromium-aluminum foil according to claim 1, characterized in that During the initial rolling, the two intermediate rollers are configured as follows: the upper and lower idle rollers are concave rollers, the curved surface depth is 0.1 mm, and the lubricant oil temperature is 40-45°C; the configuration of an intermediate double-cone roller is as follows: the cone lengths at both ends are 50-150 mm, the height difference on both sides of the cone length area is 0.07-0.1 mm, the roughness value is greater than 0.4Ra, and the thickness of the obtained semi-finished iron-chromium-aluminum coil is less than 0.1 mm.

3. The method for preparing the iron-chromium-aluminum foil according to claim 1, characterized in that The annealing temperature of the softening heat treatment is 950-1200° C., the heating speed is 10-20° C. / s, and the cooling method is furnace cooling.

4. The method for preparing the iron-chromium-aluminum foil according to claim 2, characterized in that The total deformation of the initial rolling is 90-95%, the processing rate of the first pass is controlled at 5-8%, the processing rate of each of the remaining passes is controlled at 17-32%, and the processing rate of the last pass is controlled at 4-8%.

5. The method for preparing the iron-chromium-aluminum foil according to claim 2, characterized in that The unit tension of the rolling entrance and exit of the initial rolling is controlled at 100.0-510.0 N / mm 2 (±30), the total rolling force is 100.0~150.0T, and the rolling speed is 90.0~200.0m / min.

6. The method for preparing the iron-chromium-aluminum foil according to claim 1, characterized in that The annealing temperature of the homogenization heat treatment is 910-1050° C., and the heating rate is 18-25° C. / s.

7. The method for preparing iron-chromium-aluminum foil according to claim 1, characterized in that The total rolling deformation of the cold finishing rolling is 70-80%, the first pass processing rate is controlled at 3-5%, the other passes processing rate is controlled at 10-20%, and the final pass processing rate is controlled at 5-7%.

8. The method for preparing the iron-chromium-aluminum foil according to claim 1, characterized in that The unit tension difference between the cold finishing rolling entrance and exit is 200-420N / mm 2 (±30), the total rolling force is 70.0~200.0T, and the rolling speed is 200.0~400.0m / min.

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