Method for controlling straightness and plate shape of GH4169 alloy strip

Abstract

The invention belongs to the technical field of preparation of high-temperature alloy cold-rolled strips. The invention discloses a GH4169 alloy strip straightness and plate shape control method. The method comprises the following steps that a blank is flattened; welding into a coil; carrying out cogging rolling to obtain an initial strip, detecting the flatness of the initial strip, and carrying out heat treatment according to test data of the flatness of the initial strip; carrying out intermediate process rolling to obtain an intermediate strip material, detecting the straightness of the intermediate strip material, and carrying out heat treatment according to test data of the straightness of the intermediate strip material; rolling a finished product to obtain a finished product strip, detecting the straightness of the finished product strip, and carrying out heat treatment according to test data of the straightness of the finished product strip; detecting the straightness of the finished strip subjected to heat treatment, and straightening the finished strip according to the straightness; and finally, the finished strip is subjected to stress relief annealing. The full-process control measure from the original blank to the finished strip is adopted, the straightness and the plate shape of the alloy strip are effectively improved, the strip product with good quality is obtained, and the benefit is remarkable.

Description

Technical Field

[0001] The invention belongs to the technical field of preparation and quality control of high-temperature alloy cold-rolled strips, and particularly relates to a method for controlling the flatness and plate shape of a GH4169 alloy strip. Background Art

[0002] GH4169 alloy is a nickel-chromium-iron based precipitation hardening deformation high temperature alloy. The alloy structure consists of γ matrix, GH4169 alloy is composed of amorphous phases, carbides, and strengthening phases γ″ and γ′. It is widely used in the temperature range of -253 to 650°C, with a transient application temperature of up to 800°C. The alloy exhibits high strength below 650°C and excellent fatigue, radiation, oxidation, and corrosion resistance, as well as excellent processability, weldability, and long-term structural stability, making it a key material for a wide range of applications in aviation, aerospace, nuclear energy, and the petroleum industry. GH4169 alloy metallurgical products primarily include cold-rolled strip, cold-rolled sheet, cold-drawn wire, and forged bar. Cold-rolled strip can be used to manufacture sheet metal components such as sealing rings, seals, damping rings, mounting flanges, elastic elements, and thermal insulation linings for aerospace power plants. The flatness and shape of GH4169 alloy strip significantly impact the manufacturing and performance of sheet metal parts. GH4169 alloy strip with excellent flatness and shape can enhance and improve the stamping performance of parts, facilitating the manufacturing and quality improvement of sheet metal parts.

[0003] For GH4169 alloy strip, there are the following problems: (1) It is difficult to control the straightness of the strip and the plate shape is poor Because the strip is ultra-thin, with the finished product typically having a thickness of 0.05-0.80mm, and a wide width of 200-600mm, the strip product has a high aspect ratio, sometimes exceeding 10,000. This high aspect ratio makes it difficult to control the strip's flatness and shape during the cold rolling process, leading to significant product appearance quality issues. These defects, such as break bend, wrinkle bend, edge bend, center bend, and warp, can easily occur in the cold-rolled strip, hindering its usability.

[0004] (2) The research on strip flatness and flatness control technology is not systematic and the quality is unstable Existing technologies for processing GH4169 alloy strip lack effective means for controlling the flatness and shape of the finished strip. The traditional method involves applying stretch bending straightening (or simply stretch straightening) to the finished strip at the end of the production process. This single method for improving the flatness of the alloy strip after rolling is not ideal. Actual cold working of strip involves an organic combination of cold rolling plastic deformation and heat treatment cycles from the raw strip to the finished strip. Currently, there is a lack of research on the coordinated control of the cold rolling, heat treatment, and stretch straightening processes that affect the flatness and shape of GH4169 alloy strip. Furthermore, the single stretch straightening used in existing technologies is tension straightening. While this improves the strip's appearance and shape, it increases residual stress. During the stamping process of precision sheet metal parts, this residual stress release can cause part deformation. Currently, there is a lack of research on the control of the stress relief annealing process after stretch straightening. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for controlling the flatness and flatness of GH4169 alloy strip. From the perspective of the entire process, a method is proposed to thoroughly and effectively improve the flatness of the alloy strip and effectively control the flatness of the strip, so as to solve the current problems in the production of GH4169 alloy strip and ensure its subsequent high performance and manufacturing quality of sheet metal parts.

[0006] To solve this technical problem, the technical solution of the present invention is: A method for controlling the flatness and flatness of GH4169 alloy strip is provided. The control process flow is as follows: (1) flattening of the blank → (2) welding into coils → (3) tension-controlled blank rolling → (4) flatness and flatness measurement → (5) tension-controlled heat treatment of the initial strip → (6) tension-controlled intermediate rolling → (7) flatness and flatness measurement → (8) tension-controlled heat treatment of the intermediate strip → (9) tension-controlled finished rolling → (10) flatness and flatness measurement → (11) tension-controlled heat treatment of the finished strip → (12) flatness and flatness measurement → (13) tension straightening of the finished strip → (14) stress relief annealing of the finished strip.

[0007] The process parameters of step (5) are: when d When the thickness is ≥20mm / m, control the heat treatment belt tension: 20-30KN, heat treatment temperature: 1050-1100℃, belt speed: 10-20m / min; When 5mm / m≤ d When the thickness is less than 20 mm / m, control the heat treatment belt tension: 15-25 kN, heat treatment temperature: 1000-1050 °C, belt speed: 10-20 m / min; when dWhen the thickness is less than 5mm / m, control the heat treatment belt tension: 10-15KN, heat treatment temperature: 950-1000℃, belt speed: 10-20m / min; in, d It is the horizontal warpage of the initial strip after billet rolling.

[0008] The process parameters of step (8) are: when d When the thickness is ≥20mm / m, control the heat treatment belt tension: 15-25KN, heat treatment temperature: 1050-1080℃, belt speed: 10-25m / min; When 5mm / m≤ d When the thickness is less than 20 mm / m, control the heat treatment belt tension: 10-20 kN, heat treatment temperature: 980-1050 °C, belt speed: 10-25 m / min; when d When the thickness is less than 5mm / m, control the heat treatment belt tension: 10-15KN, heat treatment temperature: 950-980℃, belt speed: 10-25m / min, in, d It is the horizontal warping of the intermediate process strip after intermediate process rolling.

[0009] The process parameters of step (11) are: when d When the strip thickness is ≥20mm / m, control the tension of the heat treatment strip: 10-20KN, heat treatment temperature: 1050-1070℃, and strip speed: 10-30m / min; When 5mm / m≤ d When the thickness is less than 20 mm / m, control the heat treatment belt tension: 10-15 kN, heat treatment temperature: 950-1050 °C, belt speed: 10-30 m / min; when d When the thickness is less than 5mm / m, control the heat treatment belt tension: 8-12KN, heat treatment temperature: 930-980℃, belt speed: 10-30 m / min, in, d It is the horizontal warping of the finished strip after rolling.

[0010] The process parameters of step (13) are: when d When the tension is ≥10mm / m, control the tension of the straightening machine to 5-15KN and the speed of the straightening machine to 1-5m / min; When 5 mm / m≤ d When the tension is less than 10 mm / m, control the tension of the straightening machine to 5-10 kN and the speed of the straightening machine to 5-10 m / min. when d When the strip thickness is less than 5mm / m, it is not necessary to straighten the finished strip. in, d It is the horizontal warpage of the finished strip after heat treatment.

[0011] By comprehensively controlling the tension process parameters in each step, the horizontal warpage of the high-temperature alloy cold-rolled strip produced by the present invention reaches d <3mm / m.

[0012] The method for controlling the flatness and flatness of the GH4169 alloy strip of the present invention adopts full-process control measures from the original billet to the finished strip, effectively improving and enhancing the flatness and flatness of the alloy strip, obtaining a strip product with good quality, and solving the problems of poor flatness of the GH4169 alloy strip in the prior art, lax flatness quality control, poor product batch stability, high scrap rate, and low pass rate.

[0013] Preferably, the process parameters of step (6) are: Cold rolling is carried out in 5-8 passes, and the deformation of each pass is controlled to be ≤18%, the rolling force of each pass is 500-850KN, the entrance tension is 45-70KN, and the exit tension is 55-80KN.

[0014] Preferably, the process parameters of step (9) are: Cold rolling is carried out in 5-9 passes, and the deformation of each pass is controlled to be ≤15%. The rolling force of each pass is 600-900KN, the entrance tension is 40-60KN, and the exit tension is 50-70KN.

[0015] Preferably, in step (14), the process parameters for stress relief annealing of the finished product are as follows: stress relief annealing process temperature: 500-550°C, tape speed: 15-40 m / min, and controlled tension of the stress relief annealing strip: 5-8 kN.

[0016] Preferably, the process parameters of step (1) are: single-pass reduction: 0.01-0.1 mm, single-pass leveling speed: 0.5-10 m / min.

[0017] Preferably, the welding process parameters of step (2) are: welding voltage: 10V~20V, welding current: 100A~150A, and controlled plasma gas consumption: 50~150 L / h; for the laser welding, the welding process parameters are: laser power: 300~800W, welding speed: 5~10 mm / s, and shielding gas: argon is used as the shielding gas, and the flow rate is controlled at 10~20 L / min.

[0018] Preferably, the welding process parameters of step (3) are: cold rolling in 5-7 passes, controlling the deformation of each pass to be ≤20%, the rolling force of each pass to be 400-600 KN, the inlet tension to be 50-80 KN, and the outlet tension to be 60-90 KN.

[0019] Specifically, the steps of the method for controlling the flatness and flatness of GH4169 alloy strip are as follows: Step 1: Flattening the blank: A single sheet of raw strip of a certain thickness is repeatedly rolled and flattened on a multi-roller flattening machine. The thickness of the raw strip is the thickness of the incoming material, which is much greater than the thickness of the finished strip. Step 2: Welding into coils: Welding several straightened original strips into coils using plasma arc welding or laser welding. Step 3, slab rolling: adopting the method of multiple passes with small deformation amount in each pass to accumulate deformation and control tension, slab rolling is performed on the coiled strip to obtain the initial strip; Step 4: Flatness and shape measurement: Cut a certain length of test strip from the initial strip and use a laser displacement sensor to measure the horizontal warpage of the test strip. d and three-dimensional contours; Step 5: Heat treatment of the initial strip: The initial strip is subjected to tension-controlled heat treatment in a continuous bright heat treatment furnace under a hydrogen atmosphere; Step 6, intermediate process rolling: adopting a method of multi-pass, small deformation amount per pass, cumulative deformation and tension control to carry out intermediate process rolling to obtain intermediate process strip; Step 7. Flatness and plate shape measurement: Cut a certain length of test strip from the intermediate process strip and use a laser displacement sensor to measure the horizontal warpage of the test strip. d and three-dimensional contours; Step 8: Heat treatment of the intermediate process strip: The intermediate process strip is subjected to tension-controlled heat treatment in a continuous bright heat treatment furnace under a hydrogen protective atmosphere; Step 9, finished product rolling: adopt the method of multiple passes, small deformation in each pass, cumulative deformation and tension control to carry out finished product finishing rolling, and roll the finished product strip into a certain thickness; Step 10: Flatness and shape measurement: Cut a certain length of test strip from the finished strip and use a laser displacement sensor to measure the horizontal warpage of the test strip. d and three-dimensional contours; Step 11: Heat treatment of finished strip: subject the finished strip to tension-controlled heat treatment in a continuous bright heat treatment furnace under hydrogen atmosphere; Step 12: Flatness and shape measurement: Cut a certain length of test strip from the finished strip after heat treatment, and use a laser displacement sensor to measure the horizontal warpage of the test strip. d and three-dimensional contours; Step 13: Finished product straightening: The finished strip is continuously stretched, bent and straightened on a multi-roller straightening unit; Step 14: Stress relief annealing of finished product: The finished strip after tensioning and straightening is subjected to stress relief annealing in a continuous bright heat treatment furnace in a hydrogen protective atmosphere, and finally a GH4169 alloy strip with good flatness and plate shape is obtained.

[0020] The beneficial effects of the present invention are: (1) A variety of process measures are adopted to control the flatness of GH4169 alloy strip throughout the entire process, especially to level the original strip blanks used, so as to control the influence on the flatness and shape of the strip from the source.

[0021] (2) In different cold rolling stages such as blank rolling, intermediate process rolling and finished product rolling, different cold rolling process parameters are optimized and configured, and a multi-pass, small deformation amount per pass cumulative deformation control tension rolling method is adopted, so that a smaller strain amount can be generated in the same rolling process, the rolling force is relatively stable, and the strip is kept uniformly deformed during the rolling process, which suppresses and reduces the probability of uneven deformation and its occurrence, and is conducive to improving the flatness of the strip and improving the plate shape.

[0022] (3) By measuring the horizontal warpage of the initial strip after slab rolling, the intermediate strip after intermediate rolling, the finished strip after finished rolling, and the finished strip after heat treatment, the horizontal warpage and plate shape test values ​​are obtained, which can effectively guide the optimization and adjustment of the initial strip heat treatment, intermediate strip heat treatment, finished strip heat treatment and straightening processes, configure the corresponding optimized process parameters, and effectively improve the control effect of the flatness and plate shape of the alloy strip.

[0023] (4) By performing stress relief annealing on the finished strip after straightening, the residual stress in the finished strip is ensured to be reduced and released, the tendency of the finished strip to deform is further controlled, and high-quality control of the flatness and plate shape of the alloy finished strip is achieved.

[0024] (5) By strictly controlling the process parameters and process coordination, a reliable and effective method for full-process control of the flatness and plate shape of the GH4169 alloy strip is provided. The horizontal warpage of the GH4169 alloy strip produced by the present invention is d <3mm / m, with good flatness and plate shape, which improves the product quality and qualified rate of GH4169 alloy strip, reduces production costs, and significantly improves the effect. DETAILED DESCRIPTION

[0025] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative work are within the scope of protection of the present invention.

[0026] The features of various aspects of the embodiments of the present invention will be described in detail below. In the detailed description below, many specific details are provided to provide a comprehensive understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention can be implemented without these specific details. The following description of the embodiments is merely intended to provide a better understanding of the present invention by illustrating examples of the present invention. The present invention is not limited to any specific configuration and method provided below, but rather encompasses all product structures, methods, and any improvements, replacements, etc., covered without departing from the spirit of the present invention.

[0027] In the following description, well-known structures and techniques are not shown to avoid unnecessarily obscuring the present invention.

[0028] Example 1: According to a preferred embodiment of a method for controlling the flatness and flatness of a GH4169 alloy strip of the present invention, the method comprises the following steps in order: The original strip blank in the form of a single sheet with a thickness of 4.0 mm was repeatedly rolled and leveled on a multi-roller leveling machine, with a single-pass reduction of 0.09 mm and a single-pass leveling speed of 3 m / min.

[0029] Several straightened original strips were welded into coils using a plasma arc welding process. The welding voltage was 20 V, the welding current was 150 A, and the plasma gas consumption was controlled at 120 L / h.

[0030] The coiled strip was rolled using a method of cumulative deformation with small deformation in each pass and tension control. Cold rolling was performed in 5 passes with deformation controlled at 20%, 15%, 14%, 13% and 10% respectively. The rolling force was 600KN per pass, the entrance tension was 80KN and the exit tension was 90KN to obtain an initial strip with a thickness of 1.8mm.

[0031] A 1000mm long test strip was cut from the 1.8mm thick initial strip and the horizontal warpage of the test strip was measured using a laser displacement sensor. d In this embodiment, the horizontal warpage of the initial strip after blanking and rolling is measured. d It is 22mm / m.

[0032] The 1.8mm thick initial strip is subjected to tension-controlled heat treatment in a continuous bright heat treatment furnace in a hydrogen protective atmosphere. The main process parameters of the tension-controlled heat treatment of the initial strip are: controlled heat treatment strip tension 30KN, heat treatment temperature: 1080℃, and strip speed: 10m / min.

[0033] The intermediate process rolling is carried out by adopting a method of cumulative deformation control with small deformation in each pass. Cold rolling is carried out in 6 passes, and the deformation of each pass is controlled to be 17.7%, 16%, 15.5%, 15%, 14.2% and 13% respectively. The rolling force of each pass is 550KN, the entrance tension is 70KN, and the exit tension is 80KN to obtain an intermediate process strip with a thickness of 0.65mm.

[0034] A 1000mm long test strip was cut from the 0.65mm thick intermediate process strip and the horizontal warpage of the test strip was measured using a laser displacement sensor. d In this embodiment, the horizontal warping of the intermediate process strip after intermediate process rolling is measured. d It is 15mm / m.

[0035] The 0.65mm intermediate process strip is subjected to tension-controlled heat treatment in a continuous bright heat treatment furnace in a hydrogen protective atmosphere. The process parameters of the tension-controlled heat treatment of the intermediate process strip are: controlled heat treatment strip tension: 20KN, heat treatment temperature: 1050℃, and strip speed: 15 m / min.

[0036] The finished product is finished by adopting a method of cumulative deformation control with multiple passes and small deformation in each pass. Cold rolling is carried out in 7 passes, and the deformation of each pass is controlled at 15%, 12.7%, 12.5%, 9.5%, 8.5%, 7.8% and 6.3% respectively. The rolling force of each pass is 650KN, the entrance tension is 50KN, and the exit tension is 65KN, and a finished strip with a thickness of 0.30mm is obtained.

[0037] A 1000mm long test strip was cut from the 0.30mm thick intermediate process strip and the horizontal warpage of the test strip was measured using a laser displacement sensor. d In this embodiment, the horizontal warpage of the finished strip after rolling is measured. d 9mm / m.

[0038] The finished strip with a thickness of 0.30 mm was subjected to tension-controlled heat treatment in a continuous bright heat treatment furnace under a hydrogen protective atmosphere. The main process parameters of the tension-controlled heat treatment of the finished strip were as follows: tension of the strip controlled at 15 kN, heat treatment temperature at 980 °C, and strip speed at 20 m / min.

[0039] A 1000mm long test strip was cut from the 0.30mm thick finished strip after heat treatment, and the horizontal warpage of the test strip was measured using a laser displacement sensor. d In this embodiment, the horizontal warpage of the finished strip after heat treatment is measured. d It is 6.8mm / m.

[0040] The finished strip with a thickness of 0.30 mm is continuously stretched, bent and straightened on a multi-roller straightening unit. The main process parameters of the straightening are to control the straightening tension: 10KN and the straightening speed: 8 m / min.

[0041] The 0.30 mm thick finished strip after tensioning and straightening was subjected to stress relief annealing in a continuous bright heat treatment furnace under a hydrogen protective atmosphere. The main process parameters were: stress relief annealing temperature: 550°C, strip speed: 35 m / min, and stress relief annealing strip tension: 8 kN. Finally, a GH4169 alloy strip with good flatness and flatness was obtained.

[0042] After random sampling and testing, the horizontal warpage of the finished product is shown in Table 1.

[0043] Example 2: According to another preferred embodiment of a method for controlling the flatness and flatness of a GH4169 alloy strip of the present invention, the method comprises the following steps in order: The original strip blank in the form of a single sheet with a thickness of 3.0 mm was repeatedly rolled and leveled on a multi-roller leveler, with a single-pass reduction of 0.07 mm and a single-pass leveling speed of 5 m / min.

[0044] Several straightened original strips were welded into coils using a laser welding process. The main process parameters of laser welding were as follows: laser power: 500 W, welding speed: 8 mm / s, argon as the shielding gas, and argon flow rate controlled at 15 L / min.

[0045] The coiled strip was rolled using a method of cumulative deformation with small deformation in each pass and tension control. Cold rolling was performed in 6 passes with deformation controlled at 16.6%, 14%, 13.3%, 11.7%, 11.6% and 10.5% respectively. The rolling force was 500KN per pass, the inlet tension was 70KN and the outlet tension was 80KN to obtain an initial strip with a thickness of 1.3mm.

[0046] A 1000mm long test strip was cut from the 1.3mm thick initial strip and the horizontal warpage of the test strip was measured using a laser displacement sensor. d In this embodiment, the horizontal warpage of the initial strip after blanking and rolling is measured. d It is 19.2mm / m.

[0047] The 1.3mm thick initial strip is subjected to tension-controlled heat treatment in a continuous bright heat treatment furnace in a hydrogen protective atmosphere. The main process parameters of the tension-controlled heat treatment of the initial strip are: controlled heat treatment strip tension 25KN, heat treatment temperature: 1050℃, and strip speed: 15m / min.

[0048] The intermediate process rolling was carried out by adopting a method of cumulative deformation control with small deformation in each pass. Cold rolling was carried out in 7 passes, and the deformation of each pass was controlled at 15.0%, 14.3%, 13.6%, 13.3%, 11.7%, 10.5% and 9% respectively. The rolling force of each pass was 700KN, the entrance tension was 60KN, and the exit tension was 75KN to obtain an intermediate process strip with a thickness of 0.5mm.

[0049] A 1000mm long test strip was cut from the 0.5mm thick intermediate process strip and the horizontal warpage of the test strip was measured using a laser displacement sensor. d In this embodiment, the horizontal warping of the intermediate process strip after intermediate process rolling is measured. d It is 12mm / m.

[0050] The 0.5mm intermediate process strip is subjected to tension-controlled heat treatment in a continuous bright heat treatment furnace in a hydrogen protective atmosphere. The process parameters of the tension-controlled heat treatment of the intermediate process strip are: controlled heat treatment strip tension: 15KN, heat treatment temperature: 1000℃, and strip speed: 20 m / min.

[0051] The finished product is finished by adopting a method of cumulative deformation control with multiple passes and small deformation in each pass. Cold rolling is carried out in 8 passes, and the deformation of each pass is controlled to be 14%, 13.9%, 13.5%, 12.5%, 12%, 10.7%, 10% and 9% respectively. The rolling force of each pass is 680KN, the entrance tension is 46KN, and the exit tension is 60KN, and a finished strip with a thickness of 0.18mm is obtained.

[0052] A 1000mm long test strip was cut from the 0.18mm thick intermediate strip and the horizontal warpage of the test strip was measured using a laser displacement sensor. d In this embodiment, the horizontal warpage of the finished strip after rolling is measured. d It is 6.2mm / m.

[0053] The finished strip with a thickness of 0.18 mm was subjected to tension-controlled heat treatment in a continuous bright heat treatment furnace under a hydrogen protective atmosphere. The main process parameters of the tension-controlled heat treatment of the finished strip were as follows: controlled heat treatment strip tension: 13 kN, heat treatment temperature: 960 °C, and strip speed: 26 m / min.

[0054] A 1000mm long test strip was cut from the 0.18mm thick finished strip after heat treatment, and the horizontal warpage of the test strip was measured using a laser displacement sensor. d In this embodiment, the horizontal warpage of the finished strip after heat treatment is measured. d It is 5.5mm / m.

[0055] The finished strip with a thickness of 0.18 mm is continuously stretched, bent and straightened on a multi-roller straightening unit. The main process parameters of the straightening are to control the straightening tension: 8KN and the straightening speed: 10 m / min.

[0056] The 0.18 mm thick finished strip after tensioning and straightening was subjected to stress relief annealing in a continuous bright heat treatment furnace under a hydrogen protective atmosphere. The main process parameters were: stress relief annealing temperature: 500°C, strip speed: 40 m / min, and stress relief annealing strip tension: 6 kN. Finally, a GH4169 alloy strip with good flatness and flatness was obtained.

[0057] After random sampling and testing, the horizontal warpage of the finished product is shown in Table 1.

[0058] Example 3: According to another preferred embodiment of a method for controlling the flatness and flatness of a GH4169 alloy strip of the present invention, the method comprises the following steps in order: The original strip blank in the form of a single sheet with a thickness of 2.0 mm was repeatedly rolled and leveled on a multi-roller leveler, with a single-pass reduction of 0.05 mm and a single-pass leveling speed of 7 m / min.

[0059] Several straightened original strips were welded into coils using a plasma arc welding process. The welding voltage was 15 V, the welding current was 120 A, and the plasma gas consumption was controlled at 100 L / h.

[0060] The coiled strip was rolled using a method of cumulative deformation with small deformation in each pass and tension control. Cold rolling was performed in 5 passes with deformation controlled at 20%, 19%, 16.6%, 14.3% and 12.5% ​​respectively. The rolling force was 450KN per pass, the inlet tension was 55KN and the outlet tension was 68KN to obtain an initial strip with a thickness of 0.8mm.

[0061] A 1000 mm long test strip was cut from a 0.8 mm thick initial strip. The horizontal warpage δ and three-dimensional profile of the test strip were measured using a laser displacement sensor. In this embodiment, the measured horizontal warpage δ of the initial strip after slab rolling was 21.6 mm / m.

[0062] The initial strip with a thickness of 0.8 mm was subjected to tension-controlled heat treatment in a continuous bright heat treatment furnace under a hydrogen protective atmosphere. The main process parameters of the tension-controlled heat treatment of the initial strip were as follows: controlled heat treatment strip tension of 22 kN, heat treatment temperature of 1060 °C, and strip speed of 12 m / min.

[0063] The intermediate process rolling is carried out by adopting a method of cumulative deformation control with small deformation in each pass. Cold rolling is carried out in 6 passes, and the deformation of each pass is controlled to be 15.5%, 14.2%, 12.5%, 10%, 9%, 8% and 7% respectively. The rolling force of each pass is 620KN, the entrance tension is 50KN, and the exit tension is 65KN to obtain an intermediate process strip with a thickness of 0.35mm.

[0064] A 1000mm long test strip was cut from the 0.35mm thick intermediate process strip and the horizontal warpage of the test strip was measured using a laser displacement sensor. d In this embodiment, the horizontal warping of the intermediate process strip after intermediate process rolling is measured. d It is 4.8mm / m.

[0065] The 0.35mm intermediate process strip is subjected to tension-controlled heat treatment in a continuous bright heat treatment furnace in a hydrogen protective atmosphere. The process parameters of the tension-controlled heat treatment of the intermediate process strip are: controlled heat treatment strip tension: 12KN, heat treatment temperature: 950℃, and strip speed: 25m / min.

[0066] The finished product is finished by adopting a method of cumulative deformation control with multiple passes and small deformation in each pass. Cold rolling is carried out in 9 passes, and the deformation of each pass is controlled at 14.6%, 14.2%, 14.0%, 13.3%, 13%, 12.5%, 12%, 11.1% and 7.6% respectively. The rolling force of each pass is 750KN, the entrance tension is 55KN, and the exit tension is 65KN, and a finished strip with a thickness of 0.1mm is obtained.

[0067] A 1000mm long test strip was cut from the 0.1mm thick intermediate process strip and the horizontal warpage of the test strip was measured using a laser displacement sensor. d In this embodiment, the horizontal warpage of the finished strip after rolling is measured. d It is 4.6mm / m.

[0068] The finished strip with a thickness of 0.1 mm was subjected to tension-controlled heat treatment in a continuous bright heat treatment furnace under a hydrogen protective atmosphere. The main process parameters of the tension-controlled heat treatment of the finished strip were as follows: controlled heat treatment strip tension: 8 kN, heat treatment temperature: 930 °C, and strip speed: 28 m / min.

[0069] A 1000mm long test strip was cut from the 0.1mm thick finished strip after heat treatment, and the horizontal warpage of the test strip was measured using a laser displacement sensor. d In this embodiment, the horizontal warpage of the finished strip after heat treatment is measured. d It is 3.5mm / m.

[0070] The 0.1 mm thick finished strip after heat treatment was subjected to stress relief annealing in a continuous bright heat treatment furnace under a hydrogen protective atmosphere. The main process parameters were: stress relief annealing process temperature: 530°C, strip speed: 30 m / min, and stress relief annealing strip tension: 5 kN. Finally, a GH4169 alloy strip with good flatness and flatness was obtained.

[0071] After random sampling and final inspection, the horizontal warpage of the finished product is shown in Table 1.

[0072] Comparative Example 1: The control method, process flow, instruments and equipment used in this comparative example for the flatness and flatness of the finished GH1469 alloy 0.30 mm thick strip are the same as those in Example 1. The differences are: In this comparative example, the horizontal warpage of the initial strip after blanking and rolling was measured. d The horizontal warpage of the intermediate strip after intermediate rolling is 22mm / m. d The horizontal warpage of the finished strip after rolling is 18mm / m. d The horizontal warpage of the finished strip after heat treatment is 11.5mm / m. d It is 7.9mm / m.

[0073] In this comparative example, the process parameters used in the initial strip tension-controlled heat treatment are shown in Table 2.

[0074] After random sampling and final inspection, the horizontal warpage test results of the finished products are shown in Table 1.

[0075] Comparative Example 2: The control method, process flow, instruments and equipment used in this comparative example for the flatness and flatness of the finished GH1469 alloy 0.18 mm thick strip are the same as those in Example 2. The differences are: In this comparative example, the horizontal warpage of the initial strip after blanking and rolling was measured. d The horizontal warpage of the intermediate strip after intermediate rolling is 19.2 mm / m. d The horizontal warpage of the finished strip after rolling is 13.6 mm / m. d The horizontal warpage of the finished strip after heat treatment is 7.5mm / m. dIt is 6.7mm / m.

[0076] In this comparative example, the process parameters used in the intermediate process of the tension-controlled heat treatment of the material are shown in Table 2.

[0077] After random sampling and final inspection, the horizontal warpage test results of the finished products are shown in Table 1.

[0078] Comparative Example 3: The control method, process flow, instruments and equipment used in this comparative example for the flatness and flatness of the finished GH1469 alloy 0.1 mm thick strip are the same as those in Example 3. The differences are: In this comparative example, the horizontal warpage δ of the initial strip after the blanking rolling was measured to be 21.6 mm / m, and the horizontal warpage δ of the intermediate strip after the intermediate rolling was measured to be d The horizontal warpage of the finished strip after rolling is 7.95mm / m. d The horizontal warpage of the finished strip after heat treatment is 6.78mm / m. d It is 5.82mm / m.

[0079] In this comparative example, the process parameters used for the initial strip tension-controlled heat treatment, the intermediate strip tension-controlled heat treatment, the finished strip tension-controlled heat treatment, and the finished product tension leveling are shown in Table 2.

[0080] After random sampling and final inspection, the horizontal warpage test results of the finished products are shown in Table 1.

[0081] Table 1

[0082] Table 2

[0083] As can be seen from Table 1, the horizontal warpage of the GH4169 alloy strips in Examples 1-3 is d The lower the horizontal warpage, the better the flatness of the strip. On the contrary, the higher the horizontal warpage, the worse the flatness of the strip. d <3mm / m, and the horizontal warpage value is very low, that is, the GH4169 alloy strip produced by the present invention has good flatness and plate shape.

[0084] As shown in Table 2, the initial strip tension-controlled heat treatment process parameters used in Comparative Example 1 differ from those required by the present invention. Combined with Table 1, it can be seen that the horizontal warpage of the GH4169 strip in Comparative Example 1 is higher than that of the strip of the same thickness in Example 1, indicating that the strip in Comparative Example 1 has poorer straightness and shape quality.

[0085] As shown in Table 2, the process parameters for the intermediate tension-controlled heat treatment of the strip used in Comparative Example 2 differ from those required by the present invention. Combined with Table 1, it can be seen that the horizontal warpage of the GH4169 strip in Comparative Example 2 is higher than that of the strip of the same thickness in Example 2, indicating that the strip in Comparative Example 2 has deteriorated in terms of flatness and shape quality.

[0086] As shown in Table 2, the process parameters used in Comparative Example 3 for the initial strip tension-controlled heat treatment, intermediate strip tension-controlled heat treatment, finished strip tension-controlled heat treatment, and finished strip tension-leveling all differ from those required by the present invention. Combined with Table 1, it can be seen that the GH4169 strip in Comparative Example 3 exhibits the highest horizontal warpage, indicating that the strip's flatness and flatness quality are the worst.

[0087] The technical solution of the present invention involves many parameters, and the synergistic effects between the various parameters need to be comprehensively considered. Only after a large number of experiments, especially the synergistic control of the process parameters in steps five, eight, eleven, and thirteen, can the beneficial effects and significant progress of the present invention be obtained.

[0088] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should all be covered by the scope of protection of the present invention.

Claims

1. A method for controlling the flatness and flatness of GH4169 alloy strip, characterized in that: The control process flow is as follows: (1) billet flattening → (2) welding into coils → (3) controlled tension billet rolling → (4) flatness and flatness measurement → (5) initial strip tension-controlled heat treatment → (6) tension-controlled intermediate rolling → (7) flatness and flatness measurement → (8) intermediate strip tension-controlled heat treatment → (9) tension-controlled finished product rolling → (10) flatness and flatness measurement → (11) finished strip tension-controlled heat treatment → (12) flatness and flatness measurement → (13) finished product straightening → (14) finished product stress relief annealing.

2. The control method according to claim 1, characterized in that: The process parameters of step (5) are: when δ When the thickness is ≥20mm / m, control the heat treatment belt tension: 20-30KN, heat treatment temperature: 1050-1100℃, belt speed: 10-20m / min; When 5mm / m≤ δ When the thickness is less than 20 mm / m, control the heat treatment belt tension: 15-25 kN, heat treatment temperature: 1000-1050 °C, belt speed: 10-20 m / min; when δ When the thickness is less than 5mm / m, control the heat treatment belt tension: 10-15KN, heat treatment temperature: 950-1000℃, belt speed: 10-20m / min; in, δ It is the horizontal warpage of the initial strip after billet rolling.

3. The control method according to claim 1, characterized in that: The process parameters of step (8) are: when δ When the thickness is ≥20mm / m, control the heat treatment belt tension: 15-25KN, heat treatment temperature: 1050-1080℃, belt speed: 10-25m / min; When 5mm / m≤ δ When the thickness is less than 20 mm / m, control the heat treatment belt tension: 10-20 kN, heat treatment temperature: 980-1050 °C, belt speed: 10-25 m / min; when δ When the thickness is less than 5mm / m, control the heat treatment belt tension: 10-15KN, heat treatment temperature: 950-980℃, belt speed: 10-25m / min, in, δ It is the horizontal warping of the intermediate process strip after intermediate process rolling.

4. The control method according to claim 1, wherein: The process parameters of step (11) are: when δ When the strip thickness is ≥20mm / m, control the tension of the heat treatment strip: 10-20KN, heat treatment temperature: 1050-1070℃, and strip speed: 10-30m / min; When 5mm / m≤ δ When the thickness is less than 20 mm / m, control the heat treatment belt tension: 10-15 kN, heat treatment temperature: 950-1050 °C, belt speed: 10-30 m / min; when δ When the thickness is less than 5mm / m, control the heat treatment belt tension: 8-12KN, heat treatment temperature: 930-980℃, belt speed: 10-30 m / min, in, δ It is the horizontal warping of the finished strip after rolling.

5. The control method according to claim 1, characterized in that: The process parameters of step (13) are: when δ When the tension is ≥10mm / m, control the tension of the straightening machine to 5-15KN and the speed of the straightening machine to 1-5m / min; When 5 mm / m≤ δ When the tension is less than 10 mm / m, control the tension of the straightening machine to 5-10 kN and the speed of the straightening machine to 5-10 m / min. when δ When the strip thickness is less than 5mm / m, it is not necessary to straighten the finished strip. in, δ It is the horizontal warpage of the finished strip after heat treatment.

6. The control method according to claim 1, characterized in that: The process parameters of step (6) are: Cold rolling is carried out in 5-8 passes, and the deformation of each pass is controlled to be ≤18%, the rolling force of each pass is 500-850KN, the entrance tension is 45-70KN, and the exit tension is 55-80KN.

7. The control method according to claim 1, characterized in that: The process parameters of step (9) are: Cold rolling is carried out in 5-9 passes, and the deformation of each pass is controlled to be ≤15%. The rolling force of each pass is 600-900KN, the entrance tension is 40-60KN, and the exit tension is 50-70KN.

8. The control method according to claim 1, characterized in that: The finished product is subjected to stress relief annealing in step (14), and the process parameters are as follows: stress relief annealing process temperature: 500-550°C, tape speed: 15-40 m / min, and stress relief annealing strip tension is controlled at 5-8 kN.

9. The control method according to claim 1, characterized in that: The process parameters of step (1) are: single-pass reduction: 0.01-0.1 mm, single-pass leveling speed: 0.5-10 m / min.

10. The control method according to claim 1, characterized in that: The welding process parameters of step (2) are: welding voltage: 10V~20V, welding current: 100A~150A, and controlled plasma gas consumption: 50~150 L / h; the welding process parameters of the laser welding are: laser power: 300~800W, welding speed: 5~10 mm / s, and shielding gas: argon is used as the shielding gas, and the flow rate is controlled at 10~20 L / min.

11. The control method according to claim 1, characterized in that: The welding process parameters of step (3) are as follows: cold rolling is performed in 5-7 passes, the deformation of each pass is controlled to be ≤20%, the rolling force of each pass is 400-600 kN, the inlet tension is 50-80 kN, and the outlet tension is 60-90 kN.

12. The control method according to claim 1, characterized in that: The method steps are as follows: Step 1: Flattening the blank: Repeatedly roll-flatten the single-sheet original strip on a multi-roller flattening machine; Step 2: Welding into coils: Welding several straightened original strips into coils using plasma arc welding or laser welding. Step 3, slab rolling: adopting the method of multiple passes with small deformation amount in each pass to accumulate deformation and control tension, slab rolling is performed on the coiled strip to obtain the initial strip; Step 4: Flatness and shape measurement: Cut a test strip from the initial strip and use a laser displacement sensor to measure the horizontal warpage of the test strip. δ and three-dimensional contours; Step 5: Heat treatment of the initial strip: The initial strip is subjected to tension-controlled heat treatment in a continuous bright heat treatment furnace under a hydrogen protective atmosphere; Step 6, intermediate process rolling: adopting a method of multi-pass, small deformation amount per pass, cumulative deformation and tension control to carry out intermediate process rolling to obtain intermediate process strip; Step 7. Flatness and plate shape measurement: Cut a test strip from the intermediate process strip and use a laser displacement sensor to measure the horizontal warpage of the test strip. δ and three-dimensional contours; Step 8: Heat treatment of the intermediate process strip: The intermediate process strip is subjected to tension-controlled heat treatment in a continuous bright heat treatment furnace under a hydrogen protective atmosphere; Step 9, Finished Product Rolling: Using a multi-pass, small deformation per pass cumulative deformation control tension method, the finished product is finished rolled into a finished strip; Step 10: Flatness and shape measurement: Cut a test strip from the finished strip and use a laser displacement sensor to measure the horizontal warpage of the test strip. δ and three-dimensional contours; Step 11: Heat treatment of finished strip: subject the finished strip to tension-controlled heat treatment in a continuous bright heat treatment furnace under hydrogen atmosphere; Step 12: Flatness and shape measurement: Cut a test strip from the finished strip after heat treatment and use a laser displacement sensor to measure the horizontal warpage of the test strip. δ and three-dimensional contours; Step 13: Finished product straightening: The finished strip is continuously stretched, bent and straightened on a multi-roller straightening unit; Step 14: Stress relief annealing of finished product: The finished strip after tensioning and straightening is subjected to stress relief annealing in a continuous bright heat treatment furnace in a hydrogen protective atmosphere, and finally a GH4169 alloy strip with good flatness and plate shape is obtained.

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