A method for improving the solidification stability of thin strip cast stainless steel

Abstract

The present application relates to the technical field of stainless steel thin strip continuous casting, and provides a method for improving the solidification stability of thin strip continuous casting stainless steel, which comprises the following steps: obtaining an initial parameter set of the thin strip; obtaining an initial process parameter set; performing thin strip continuous casting in combination with the obtained process parameter set; measuring the molten pool liquid level, the casting and rolling force, the casting roll surface temperature and the casting strip surface temperature in real time during the thin strip continuous casting process; judging according to a judgment condition; if adjustment is needed, obtaining an adjusted process parameter set and returning; otherwise, proceeding to the next step; completing the thin strip continuous casting to obtain a thin strip product. In the present application, the molten pool liquid level, the casting and rolling force, the casting roll surface temperature and the casting strip surface temperature during the thin strip continuous casting process are measured in real time and judged according to corresponding judgment conditions, and through the establishment of real-time collaborative control of "liquid level-heat transfer-casting and rolling force-roll gap", the surface quality and the microstructure uniformity are improved while ensuring the continuous and stable production of stainless steel casting strip with a thickness of ≤2 mm.

Description

Technical Field

[0001] This invention relates to the field of stainless steel strip continuous casting technology, and specifically to a method for improving the solidification stability of stainless steel strips in continuous casting. Background Technology

[0002] Twin-roll strip casting (TRC) technology can directly produce thin strips of 2–4 mm thickness from molten steel. Combined with hot rolling, it can realize short-process integrated casting and rolling, which is beneficial for energy saving, consumption reduction and material refinement.

[0003] Thin-strip continuous casting technology for stainless steel directly produces millimeter-thick strips through an integrated "casting-rolling" process, representing a key breakthrough in the green and efficient transformation of the steel industry. By directly producing 1-2mm thick strips through sub-rapid solidification of molten steel between counter-rotating crystallizing rolls (cooling rate 1000–1700℃ / s), it overturns the traditional kilometer-scale process of slab continuous casting + hot rolling, achieving an 80% reduction in energy consumption per ton of steel and a 90% reduction in carbon footprint. It is particularly suitable for the production of high-alloy stainless steels such as 304 / 316L.

[0004] However, this technology faces a bottleneck of multi-factor coupling instability—fluctuations in the molten pool level (±3mm) and thermal deformation of the casting rolls cause deviations in the thickness of the cast strip, central shrinkage cavities, and surface vibration marks, which seriously restrict the continuous and stable production of ultra-thin strips. It is urgent to develop a collaborative control model of liquid level-heat transfer-casting force-roll gap to break through the bottleneck of industrial mass production.

[0005] The following solutions are disclosed in the prior art:

[0006] The invention patent with publication number CN120079820B and patent title "Method and Apparatus, Medium and Terminal for Determining Process Parameters of Thin Strip Continuous Casting Machine" discloses the following: a fully coupled model of process parameters of thin strip continuous casting machine is pre-constructed; the casting machine process parameters required to control the casting machine are determined according to the fully coupled model; the initial values ​​of the casting machine process parameters for the current casting are determined by optimizing the casting machine process parameters recorded from historical casting production data; and the correction values ​​of solidification parameters, rolling parameters, casting and rolling forces, and casting speed are calculated based on the periodic production data of the stable state cycle and the fully coupled model of process parameters of thin strip continuous casting machine. The initial values ​​of the casting machine process parameters are then adjusted based on the above parameters.

[0007] The invention application with publication number CN119282050A and patent title "Method and Control System for Starting Casting of Twin-Roll Thin Strip" discloses: setting continuous casting parameters for the starting casting process, including at least the upper limit of casting force F-(upset), the lower limit of casting force F-(downset), the target roll gap S-(target), and the initial roll surface speed V-0; starting casting, keeping the roll gap S at the target roll gap S-(target), and monitoring the molten pool liquid level height L and the actual casting force F-(actual) in real time; when the molten pool liquid level height L reaches the set value L-(set), controlling the molten pool liquid level height L to be stable within the target range through a first closed-loop control loop related to the casting flow rate Q, and controlling the casting force F-(actual) to be stable within the target range through a second closed-loop control loop composed of the casting force F-(actual) and the roll surface speed V-(actual) as variables. The casting method provided by this invention can avoid the problem of roll gap fluctuation caused by fluctuation of casting and rolling force. The decoupling of liquid level closed-loop control and casting and rolling force-speed closed-loop control simplifies the system adjustment process and improves the system stability and control accuracy.

[0008] The invention patent with publication number CN114713780B and patent title "A Method for Improving the Solidification Stability of Molten Silicon Steel into Strip in Thin Strip Continuous Casting Process" discloses that: molten metal flows through the overflow port at the bottom of the distributor to a pair of casting rolls of a twin-roll continuous casting machine, and forms a molten pool above the roll gap between the pair of casting rolls and above the casting surface of the casting rolls. The overflow port is immersed in the molten pool to a certain depth (d), the depth being selected from the range of 30mm to 50mm. The molten metal in the molten pool contains one or both of selenium (Se) and tellurium (Te), and the total content of selenium (Se) and tellurium (Te) is ≥0.006% by weight. The pair of casting rolls rotate relative to each other, and the molten metal in the molten pool cools and solidifies on the casting surface of the casting rolls and passes downward through the roll gap between the pair of casting rolls to form a steel strip. The rotational linear speed of the casting rolls is ≤0.9m / s.

[0009] However, the existing technology has the following drawbacks: ① Model lag: It relies on historical data for optimization and cannot respond to transient fluctuations in the molten pool in real time (such as when the liquid level changes by ±5mm, the adjustment delay is >10s), which leads to an increase in the strip breakage rate during the casting stage; ② Liquid level and casting force are independent closed loops, and no interactive compensation mechanism has been established; the thermal balance of the side sealing plate-molten pool interface is not monitored; and the impact of the heat transfer process on casting is not analyzed; ③ Stable strip formation methods are only applicable to some steel grades and are not suitable for stable strip formation of stainless steel.

[0010] In summary, there is an urgent need for a method that can effectively improve the solidification stability of thin strip continuously cast stainless steel to solve the problems existing in the prior art. Summary of the Invention

[0011] The purpose of this invention is to provide a method for improving the solidification stability of thin-strip continuously cast stainless steel, and the specific technical solution is as follows:

[0012] A method for improving the solidification stability of thin strip continuously cast stainless steel includes the following steps:

[0013] Step 1: Obtain the initial parameter set of the thin strip;

[0014] Step 2: Based on the initial parameter set obtained in Step 1, obtain the initial process parameter set; the process parameter set includes the casting speed Vc, cooling water flow rate Qw, casting temperature T0, expected casting roll surface temperature Ttarget1, expected casting strip surface temperature Ttarget2, set roll gap value Starget, target liquid level Lset, and molten steel flow rate Qm.

[0015] Step 3: Perform thin strip continuous casting based on the obtained process parameter set;

[0016] Step 4: Real-time measurement of molten pool level L, casting force Factual, casting roll surface temperature Tr, and casting strip surface temperature Ts during the thin strip continuous casting process;

[0017] Step 5: Make a judgment based on the judgment conditions. If adjustment is required, obtain the adjusted set of process parameters and return to Step 3; otherwise, proceed to the next step. The judgment conditions include the judgment of casting and rolling force Factual, molten pool level L, casting roll surface temperature Tr, casting strip surface temperature Ts, and dynamic compensation adjustment of roll gap.

[0018] Step 6: Complete the thin strip continuous casting to obtain the thin strip product.

[0019] Preferably, the judgment conditions in step five are as follows:

[0020] Condition ①, For the casting and rolling force Factual: If Factual - Fpredict > 2% × Fpredict, then increase the roll gap value Starget by 1%; if Fpredict - Factual > 2% × Fpredict, then decrease the roll gap value Starget by 1%; Fpredict is the predicted value of the casting and rolling force, Fpredict = K × ΔS, K is a coefficient determined by the properties of the thin strip continuous casting equipment itself, and ΔS is the expansion value of the roll gap value Starget;

[0021] Condition ②, for the molten pool level L: the molten steel flow rate Qm is controlled by an electromagnetic stopper rod. Specifically: if the molten pool level L - target level Lset > 1.0 mm, then the molten steel flow rate Qm is reduced by 5%; if the target level Lset - molten pool level L > 1.0 mm, then the molten steel flow rate Qm is increased by 5%.

[0022] Condition ③, Regarding the surface temperature Tr of the casting roll: If the surface temperature Tr of the casting roll - the expected surface temperature Ttarget1 of the casting roll > 5% × the expected surface temperature Ttarget1 of the casting roll, then increase the cooling water flow rate Qw by 1%; if the expected surface temperature Ttarget1 of the casting roll - the surface temperature Tr of the casting roll > 5% × the expected surface temperature Ttarget1 of the casting roll, then decrease the cooling water flow rate Qw by 1%.

[0023] Condition 4, Regarding the surface temperature Ts of the cast strip: For the cast strip at the exit roll, if the surface temperature Ts of the cast strip - the expected surface temperature Ttarget2 of the cast strip > 5% × the expected surface temperature Ttarget2 of the cast strip, then decrease the pulling speed Vc by 1% until |the surface temperature Ts of the cast strip - the expected surface temperature Ttarget2 of the cast strip| ≤ 5% × the expected surface temperature Ttarget2 of the cast strip; if the expected surface temperature Ttarget2 of the cast strip - the surface temperature Ts of the cast strip > 5% × the expected surface temperature Ttarget2 of the cast strip, then increase the pulling speed Vc by 1% until |the surface temperature Ts of the cast strip - the expected surface temperature Ttarget2 of the cast strip| ≤ 5% × the expected surface temperature Ttarget2 of the cast strip.

[0024] Condition 5: The roll gap dynamic compensation model shall be used for compensation according to the following formula:

[0025] Starget(i)=Starget(i-1)+ΔSthermal+ΔSshrink;

[0026] Where: Starget(i) is the expansion value of the roll gap Starget after the i-th compensation, and the value of i is greater than or equal to 1; Starget(0) = the set roll gap value Starget; ΔSthermal is the thermal deformation compensation amount, which is related to the thermal expansion coefficient αroll of the casting roll, the temperature rise of the casting roll ΔTroll, and the diameter of the casting roll Droll; ΔSthermal = αroll × ΔTroll × Droll; the temperature rise of the casting roll ΔTroll = the surface temperature of the casting roll Tr - room temperature TR; ΔSshrink is the solidification shrinkage compensation amount, which is related to the linear shrinkage coefficient β; ΔSshrink = β × (TL - TS) × Starget; TL is the liquidus temperature, and TS is the solidus temperature.

[0027] Preferably, obtaining the initial parameter set of the thin strip in step one specifically includes:

[0028] Input basic parameters, including stainless steel physical properties and casting temperature T0; stainless steel physical properties include density versus temperature curve, thermal conductivity versus temperature curve, specific heat capacity versus temperature curve, latent heat of solidification, liquidus temperature, solidus temperature, and linear shrinkage coefficient, which are used to obtain the expected casting roll surface temperature Ttarget1, expected strip exit temperature Ttarget2, solidification shrinkage compensation ΔSshrink, and expected heat flux density q0 through finite element calculation;

[0029] The equipment process parameters include the diameter of the casting roll, the material of the casting roll, the coefficient of thermal expansion of the casting roll, the cooling water flow rate Qw, and the arc length of the molten pool Lh.

[0030] Preferably, the target liquid level Lset is obtained based on the set roll gap value Starget, and the process is as follows:

[0031] The solidification thickness d on one side of the cast strip is calculated using the following formula:

[0032] d = k×t (1 / 2) ;

[0033] Where: t is the contact time between the molten steel and the crystallizing roll, t = arc length of the molten pool Lh / casting speed Vc; k is the solidification coefficient;

[0034] The set roll gap value Starget is calculated using the following formula:

[0035] Starget = 2d = 2k × (Lh / Vc) (1 / 2) ;

[0036] The formula for calculating the arc length Lh of the molten pool is as follows:

[0037] Lh = Vc × (Starget / 2k) 2 ;

[0038] The target liquid level Lset is calculated based on the molten pool arc length Lh using the following formula:

[0039] .

[0040] The effect of applying the technical solution of this invention is:

[0041] This invention discloses a method for improving the solidification stability of stainless steel strip in continuous casting, comprising: obtaining an initial parameter set of the strip; obtaining an initial process parameter set based on the initial parameter set; performing continuous casting of the strip using the obtained process parameter set; measuring the molten pool level L, casting force Factual, casting roll surface temperature Tr, and strip surface temperature Ts in real time during the continuous casting process; making judgments based on judgment conditions, and if adjustments are needed, obtaining the adjusted process parameter set and returning; otherwise, proceeding to the next step; completing the continuous casting of the strip to obtain the strip product. In this invention, the real-time measurement of the molten pool level L, casting force Factual, casting roll surface temperature Tr, and strip surface temperature Ts during the continuous casting process, and the judgment based on corresponding judgment conditions, establishes a real-time collaborative control of "level-heat transfer-casting force-roll gap," ensuring continuous and stable production of ≤2mm ultra-thin stainless steel strip while improving surface quality and microstructure uniformity.

[0042] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0043] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0044] Figure 1 This is a schematic diagram of a thin strip continuous casting system performing thin strip continuous casting in an embodiment of the present invention;

[0045] Figure 2 This is a schematic diagram illustrating the principle of a method for improving the solidification stability of thin-strip continuous casting stainless steel according to an embodiment of the present invention.

[0046] Among them: 1-Atmosphere protection induction furnace; 2-Flow distributor; 3-Camera; 4-Roller brush; 5-Crystallizing roller; 6-Temperature measuring instrument; 7-Sealed guide rail; 8-Slag tray; 9-Conveying roller; 10-Cooling device; 11-Curling. Detailed Implementation

[0047] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered by the claims.

[0048] Example:

[0049] A method for improving the solidification stability of stainless steel in thin strip continuous casting, wherein the thin strip continuous casting system used is an existing system, such as... Figure 1As shown, it specifically includes: atmosphere-protected induction furnace 1, flow distributor 2, roller brush 4, crystallizing roller 5, sealed guide rail 7, slag tray 8, conveying roller 9, and cooling device 10. Molten steel flows into the flow distributor 2 after passing through the atmosphere-protected induction furnace 1, and then passes through two sets of crystallizing rollers 5 with roller brush 4 to form a thin strip. It is then conveyed forward by the sealed guide rail 7 and the conveying roller 9, and then cooled by the cooling device 10, finally forming a stainless steel thin strip curl 11.

[0050] In this embodiment, cameras 3 are installed at corresponding positions below the distributor 2 and the crystallizing roller 5; thermometers 6 are installed below the crystallizing roller 5 and behind the cooling device 10; and slag trays 8 are provided below the two sets of crystallizing rollers 5.

[0051] For details of the method for improving the solidification stability of stainless steel in thin strip continuous casting, please refer to [link to relevant documentation]. Figure 2 This includes the following steps:

[0052] Step 1: Obtain the initial parameter set of the thin strip;

[0053] Step 2: Based on the initial parameter set obtained in Step 1, obtain the initial process parameter set; the process parameter set includes the casting speed Vc, cooling water flow rate Qw, casting temperature T0, expected casting roll surface temperature Ttarget1, expected casting strip surface temperature Ttarget2, set roll gap value Starget, target liquid level Lset, and molten steel flow rate Qm.

[0054] Step 3: Perform thin strip continuous casting based on the obtained process parameter set;

[0055] Step 4: Real-time measurement of molten pool level L, casting force Factual, casting roll surface temperature Tr, and casting strip surface temperature Ts during the thin strip continuous casting process;

[0056] Step 5: Make a judgment based on the judgment conditions. If adjustment is required, obtain the adjusted set of process parameters and return to Step 3; otherwise, proceed to the next step. The judgment conditions include the judgment of casting and rolling force Factual, molten pool level L, casting roll surface temperature Tr, casting strip surface temperature Ts, and dynamic compensation adjustment of roll gap.

[0057] Step 6: Complete the thin strip continuous casting to obtain the thin strip product.

[0058] Preferably, the judgment conditions in step five are as follows:

[0059] Condition ①, For the casting and rolling force Factual: If Factual - Fpredict > 2% × Fpredict, then increase the roll gap value Starget by 1%; if Fpredict - Factual > 2% × Fpredict, then decrease the roll gap value Starget by 1%; Fpredict is the predicted value of the casting and rolling force, Fpredict = K × ΔS, K is a coefficient determined by the properties of the thin strip continuous casting equipment itself, and ΔS is the expansion value of the roll gap value Starget;

[0060] Condition ②, for the molten pool level L: the molten steel flow rate Qm is controlled by an electromagnetic stopper rod. Specifically: if the molten pool level L - target level Lset > 1.0 mm, then the molten steel flow rate Qm is reduced by 5%; if the target level Lset - molten pool level L > 1.0 mm, then the molten steel flow rate Qm is increased by 5%.

[0061] Condition ③, Regarding the surface temperature Tr of the casting roll: If the surface temperature Tr of the casting roll - the expected surface temperature Ttarget1 of the casting roll > 5% × the expected surface temperature Ttarget1 of the casting roll, then increase the cooling water flow rate Qw by 1%; if the expected surface temperature Ttarget1 of the casting roll - the surface temperature Tr of the casting roll > 5% × the expected surface temperature Ttarget1 of the casting roll, then decrease the cooling water flow rate Qw by 1%.

[0062] Condition 4, Regarding the surface temperature Ts of the cast strip: For the cast strip at the exit roll, if the surface temperature Ts of the cast strip - the expected surface temperature Ttarget2 of the cast strip > 5% × the expected surface temperature Ttarget2 of the cast strip, then decrease the pulling speed Vc by 1% until |the surface temperature Ts of the cast strip - the expected surface temperature Ttarget2 of the cast strip| ≤ 5% × the expected surface temperature Ttarget2 of the cast strip; if the expected surface temperature Ttarget2 of the cast strip - the surface temperature Ts of the cast strip > 5% × the expected surface temperature Ttarget2 of the cast strip, then increase the pulling speed Vc by 1% until |the surface temperature Ts of the cast strip - the expected surface temperature Ttarget2 of the cast strip| ≤ 5% × the expected surface temperature Ttarget2 of the cast strip.

[0063] Condition 5: The roll gap dynamic compensation model shall be used for compensation according to the following formula:

[0064] Starget(i)=Starget(i-1)+ΔSthermal+ΔSshrink;

[0065] Where: Starget(i) is the expansion value of the roll gap Starget after the i-th compensation, and the value of i is greater than or equal to 1; Starget(0) = the set roll gap value Starget; ΔSthermal is the thermal deformation compensation amount, which is related to the thermal expansion coefficient αroll of the casting roll, the temperature rise of the casting roll ΔTroll, and the diameter of the casting roll Droll; ΔSthermal = αroll × ΔTroll × Droll; the temperature rise of the casting roll ΔTroll = the surface temperature of the casting roll Tr - room temperature TR; ΔSshrink is the solidification shrinkage compensation amount, which is related to the linear shrinkage coefficient β; ΔSshrink = β × (TL - TS) × Starget; TL is the liquidus temperature, and TS is the solidus temperature.

[0066] Preferably, obtaining the initial parameter set of the thin strip in step one specifically includes:

[0067] Input basic parameters, including stainless steel physical properties and casting temperature T0; stainless steel physical properties include density versus temperature curve, thermal conductivity versus temperature curve, specific heat capacity versus temperature curve, latent heat of solidification, liquidus temperature, solidus temperature, and linear shrinkage coefficient, which are used to obtain the expected casting roll surface temperature Ttarget1, expected strip exit temperature Ttarget2, solidification shrinkage compensation ΔSshrink, and expected heat flux density q0 through finite element calculation;

[0068] The equipment process parameters include the diameter of the casting roll, the material of the casting roll, the coefficient of thermal expansion of the casting roll, the cooling water flow rate Qw, and the arc length of the molten pool Lh.

[0069] Preferably, the target liquid level Lset is obtained based on the set roll gap value Starget, and the process is as follows:

[0070] The solidification thickness d on one side of the cast strip is calculated using the following formula:

[0071] d = k×t (1 / 2) ;

[0072] Where: t is the contact time between the molten steel and the crystallizing roll, t = arc length of the molten pool Lh / casting speed Vc; k is the solidification coefficient;

[0073] The set roll gap value Starget is calculated using the following formula:

[0074] Starget = 2d = 2k × (Lh / Vc) (1 / 2) ;

[0075] The formula for calculating the arc length Lh of the molten pool is as follows:

[0076] Lh = Vc × (Starget / 2k) 2 ;

[0077] The target liquid level Lset is calculated based on the molten pool arc length Lh using the following formula:

[0078] .

[0079] Application examples:

[0080] The casting process, using 304 stainless steel as the specific production object, involves the following steps:

[0081] Step 1: Obtain the initial parameter set for the thin strip, including: the chemical composition of 304 stainless steel is 18% Cr, 8% Ni, 0.08% C, 2% Mn, 0.75% Si, with the balance being Fe; the required strip thickness is 2.5 mm and the width is 100 mm; set the roll gap S=S0=2.5 ​​mm based on the strip thickness; calculate the thermophysical parameters of the steel grade based on the steel grade and chemical composition: density 7.93 g / cm³. 3 Liquidus temperature (Tl=1460℃), solidus temperature (Ts=1420℃), specific heat capacity 0.502 J / (g·℃), thermal conductivity 16.3 W / (m·℃), coefficient of linear expansion 16.0×10⁻⁶ -6 / ℃.

[0082] Step 2: Based on the initial parameter set of the thin strip, the three-dimensional transient calculation model is used for offline pre-calculation (this part belongs to the prior art and can be referred to the prior art) to obtain the main initial process parameter set, including the pulling speed Vc=30 m / min and the cooling water flow rate Qw=100 m³ / min. 3 / h, casting temperature T0=1520℃, expected casting roll surface temperature Ttarget1=400℃, expected strip exit temperature Ttarget2=1300℃, Htarget=2.5mm and target liquid level Lset=120mm;

[0083] Step 3: Perform continuous casting of 304 stainless steel thin strips based on the process parameter set;

[0084] Step 4: Real-time measurement of molten pool level L, casting force Factual, casting roll surface temperature Tr, and casting strip surface temperature Ts during the continuous casting process of 304 stainless steel strip;

[0085] Step 5: Make a judgment based on the judgment conditions, as follows:

[0086] Condition ①, Casting and rolling force Factual: Abnormal fluctuations in casting and rolling force occurred at 20s and 45s during the casting process. The casting and rolling force Factual = 13KN, and the predicted value of casting and rolling force Fpredict is 10KN. Therefore, Factual - Fpredict = 13KN - 10KN = 3KN, and 2% × Fpredict = 2% × 10KN = 0.2KN. Thus, Factual - Fpredict > 2% × Fpredict, which exceeds the reasonable fluctuation range. At this time, the roll gap was increased by 5%, and the measured casting and rolling force Factual = 10.15KN was obtained. |Factual - Fpredict| < 2% × Fpredict, and the casting and rolling force returned to the error range of the predicted value.

[0087] Condition ②: The molten pool level L is stable at Lset±1.0mm. After 10s of casting, the molten pool level abnormally increases to 125mm. At this time, the steel injection volume is reduced by 2%, and the level returns to the normal value of 120mm.

[0088] Condition ③: The surface temperature Tr of the casting roll did not show any abnormalities;

[0089] Condition 4: The surface temperature Ts of the cast strip did not show any abnormalities;

[0090] Condition 5: The dynamic compensation model for the roll gap considers the thermal deformation and solidification shrinkage of the casting roll. During the casting process, because the casting time is short, the casting roll does not undergo significant thermal deformation, and the solidification shrinkage of 304 stainless steel does not have any effect on the roll gap setting size other than the error amount.

[0091] Step Six: Complete the thin strip continuous casting to obtain the thin strip product. All 50kg of molten steel was poured, forming a strip over 10 meters long. The casting process was stable, with no strip breakage, and the strip was successfully rolled.

[0092] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for improving the solidification stability of thin-strip continuously cast stainless steel, characterized in that, Includes the following steps: Step 1: Obtain the initial parameter set of the thin strip; Step 2: Based on the initial parameter set obtained in Step 1, obtain the initial process parameter set; the process parameter set includes the casting speed Vc, cooling water flow rate Qw, casting temperature T0, expected casting roll surface temperature Ttarget1, expected casting strip surface temperature Ttarget2, set roll gap value Starget, target liquid level Lset, and molten steel flow rate Qm. Step 3: Perform thin strip continuous casting based on the obtained process parameter set; Step 4: Real-time measurement of molten pool level L, casting force Factual, casting roll surface temperature Tr, and casting strip surface temperature Ts during the thin strip continuous casting process; Step 5: Make a judgment based on the judgment conditions. If adjustments are needed, obtain the adjusted set of process parameters and return to Step 3. Otherwise, proceed to the next step; the judgment conditions include the judgment of the casting and rolling force (Factual), the molten pool level (L), the surface temperature of the casting roll (Tr), the surface temperature of the casting strip (Ts), and the dynamic compensation adjustment of the roll gap. Step 6: Complete the thin strip continuous casting to obtain the thin strip product; The judgment conditions in step five are as follows: Condition ①, For the casting and rolling force Factual: If Factual - Fpredict > 2% × Fpredict, then increase the roll gap value Starget by 1%; if Fpredict - Factual > 2% × Fpredict, then decrease the roll gap value Starget by 1%; Fpredict is the predicted value of the casting and rolling force, Fpredict = K × ΔS, K is a coefficient determined by the properties of the thin strip continuous casting equipment itself, and ΔS is the expansion value of the roll gap value Starget; Condition ②, for the molten pool level L: the molten steel flow rate Qm is controlled by an electromagnetic stopper rod. Specifically: if the molten pool level L - target level Lset > 1.0 mm, then the molten steel flow rate Qm is reduced by 5%; if the target level Lset - molten pool level L > 1.0 mm, then the molten steel flow rate Qm is increased by 5%. Condition ③, Regarding the surface temperature Tr of the casting roll: If the surface temperature Tr of the casting roll - the expected surface temperature Ttarget1 of the casting roll > 5% × the expected surface temperature Ttarget1 of the casting roll, then increase the cooling water flow rate Qw by 1%; if the expected surface temperature Ttarget1 of the casting roll - the surface temperature Tr of the casting roll > 5% × the expected surface temperature Ttarget1 of the casting roll, then decrease the cooling water flow rate Qw by 1%. Condition 4, Regarding the surface temperature Ts of the cast strip: For the cast strip at the exit roll, if the surface temperature Ts of the cast strip - the expected surface temperature Ttarget2 of the cast strip > 5% × the expected surface temperature Ttarget2 of the cast strip, then decrease the pulling speed Vc by 1% until |the surface temperature Ts of the cast strip - the expected surface temperature Ttarget2 of the cast strip| ≤ 5% × the expected surface temperature Ttarget2 of the cast strip; if the expected surface temperature Ttarget2 of the cast strip - the surface temperature Ts of the cast strip > 5% × the expected surface temperature Ttarget2 of the cast strip, then increase the pulling speed Vc by 1% until |the surface temperature Ts of the cast strip - the expected surface temperature Ttarget2 of the cast strip| ≤ 5% × the expected surface temperature Ttarget2 of the cast strip. Condition 5: The roll gap dynamic compensation model shall be used for compensation according to the following formula: Starget(i)=Starget(i-1)+ΔSthermal+ΔSshrink; Where: Starget(i) is the expansion value of the roll gap Starget after the i-th compensation, and the value of i is greater than or equal to 1; Starget(0) = the set roll gap value Starget; ΔSthermal is the thermal deformation compensation amount, which is related to the thermal expansion coefficient αroll of the casting roll, the temperature rise of the casting roll ΔTroll, and the diameter of the casting roll Droll; ΔSthermal = αroll × ΔTroll × Droll; the temperature rise of the casting roll ΔTroll = the surface temperature of the casting roll Tr - room temperature TR; ΔSshrink is the solidification shrinkage compensation amount, which is related to the linear shrinkage coefficient β; ΔSshrink = β × (TL - TS) × Starget; TL is the liquidus temperature, and TS is the solidus temperature. The target liquid level Lset is obtained based on the set roll gap value Starget, and the process is as follows: The solidification thickness d on one side of the cast strip is calculated using the following formula: d = k×t (1 / 2) ; Where: t is the contact time between the molten steel and the crystallizing roll, t = arc length of the molten pool Lh / casting speed Vc; k is the solidification coefficient; The set roll gap value Starget is calculated using the following formula: Starget=2d= 2k×(Lh / Vc) (1 / 2) ; The formula for calculating the arc length Lh of the molten pool is as follows: Lh=Vc×(Starget / 2k) 2 ; The target liquid level Lset is calculated based on the molten pool arc length Lh using the following formula: 。 2. The method for improving the solidification stability of thin-strip continuously cast stainless steel according to claim 1, characterized in that, Step one, obtaining the initial parameter set of the thin strip, specifically includes: Input basic parameters, including stainless steel physical properties and casting temperature T0; stainless steel physical properties include density versus temperature curve, thermal conductivity versus temperature curve, specific heat capacity versus temperature curve, latent heat of solidification, liquidus temperature, solidus temperature, and linear shrinkage coefficient, which are used to obtain the expected casting roll surface temperature Ttarget1, expected strip exit temperature Ttarget2, solidification shrinkage compensation ΔSshrink, and expected heat flux density q0 through finite element calculation; The equipment process parameters include the diameter of the casting roll, the material of the casting roll, the coefficient of thermal expansion of the casting roll, the cooling water flow rate Qw, and the arc length of the molten pool Lh.

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