6061 aluminum alloy plate ingot casting anti-cracking process control method and system

Abstract

The invention discloses a 6061 aluminum alloy plate ingot casting anti-edge-cracking process control method and system, and solves the technical problem of easy edge cracking in a 6061 aluminum alloy plate ingot hot rolling process by accurately controlling casting key process parameters, improving materials and operation specifications and establishing a systematic monitoring management mechanism. The technological parameters comprise the casting speed of 42-44 mm / min, the casting temperature of 725-730 DEG C and the like, the material and operation improvement comprises the steps of controlling the content of a microelement Pb to be smaller than or equal to 0.02%, adopting an aluminum ingot to replace a silicon plate for cooling and the like, and the systematic monitoring management comprises a one-furnace-one-book recording system and a multi-post collaborative principal system. The process control system comprises a temperature monitoring module, a flow control module and the like. The invention provides a systematized anti-cracking edge solution covering multiple dimensions of process parameters, materials, equipment, management and the like, so that the cracking edge feedback rate is reduced from 3.07% to 0.76%, about 18,225 thousand yuan of economic benefit is comprehensively created each month, the product quality, the yield and the production safety are remarkably improved, and the method is suitable for standardized popularization of aluminum alloy casting enterprises.

Description

Technical Field

[0001] This invention relates to the field of aluminum alloy casting technology, specifically to a method and system for preventing edge cracking in the casting of 6061 aluminum alloy plates. Background Technology

[0002] 6061 aluminum alloy possesses excellent comprehensive properties, including moderate strength, strong corrosion resistance, and good machinability, making it widely used in aerospace, transportation, and machinery manufacturing industries. However, during the hot rolling process of 6061 aluminum alloy ingots, edge cracking is highly likely to occur. This problem seriously affects the yield rate and poses a potential safety hazard to subsequent production processes.

[0003] The main reasons for edge cracking in 6061 aluminum alloy ingots during hot rolling include the following:

[0004] First, improper control of casting process parameters, such as unreasonable settings of casting speed, initial pouring temperature, and cooling system parameters, leads to uneven internal structure and stress concentration in the ingot.

[0005] Secondly, unstable equipment conditions, such as wear of the crystallizer and blockage of oil and water circuits, affect the stability of the casting process.

[0006] Third, excessive trace elements in raw materials, such as excessive Pb content, can damage the microstructure of aluminum alloys and reduce the toughness of the material.

[0007] Current technologies lack a systematic process control scheme, with each stage controlled independently, failing to achieve a synergistic effect. This results in a persistently high hot-rolling edge cracking feedback rate, causing not only significant waste generation and increased production costs but also impacting the company's economic benefits and market competitiveness. Therefore, there is an urgent need to develop a technical solution that can address the edge cracking problem from multiple dimensions. Summary of the Invention

[0008] The purpose of this invention is to provide a method and system for preventing edge cracking in the casting process of 6061 aluminum alloy plate ingots. Through multi-parameter collaborative control, material and operation improvement, and systematic management, it aims to significantly reduce the occurrence rate of hot rolling edge cracking, increase the yield, improve production safety, and create considerable economic benefits.

[0009] To achieve the above objectives, the present invention provides the following technical solution:

[0010] A method for preventing edge cracking during the casting of 6061 aluminum alloy plate ingots includes the following steps:

[0011] S1: Process parameter control, which coordinates the control of parameters during the casting process. These parameters include casting speed, initial pouring temperature, water flow rate, water temperature, crystallizer liquid level height, and small-face cooling water valve opening.

[0012] S2: Material and operational improvements, control of trace element content in raw materials, improvement of cooling methods and equipment maintenance standards;

[0013] S3: Systematic monitoring and management, standardizing management systems and job responsibilities.

[0014] Furthermore, in S1, process parameter control includes the following steps:

[0015] (1) Control the casting speed to 42–44 mm / min;

[0016] (2) Control the initial pouring temperature to 725–730°C;

[0017] (3) Control the liquid level in the crystallizer to be 7.5–8 cm from the top edge;

[0018] (4) Control the water flow rate to 260–275 m³ / h;

[0019] (5) Control the water temperature to 28–33°C;

[0020] (6) The opening of the small cooling water valve should be controlled at 50% of the scale, and it is strictly forbidden to adjust it privately.

[0021] Furthermore, S1 also includes controlling the temperature at the end of the casting section, specifically:

[0022] The temperature of the casting end section (0–300 mm) is controlled at 660–680°C.

[0023] The temperature of the casting end section (300–500 mm) is controlled at 680–695°C.

[0024] The temperature of the casting end section (500–700 mm) is controlled at 695–700°C.

[0025] The temperature is controlled at 695–705°C from the end of casting (700mm from the casting tip) to the end of casting.

[0026] Furthermore, in S2, material and operational improvements include the following steps:

[0027] (1) The lead (Pb) content in the alloy shall not exceed 0.02%;

[0028] (2) Use aluminum ingots instead of silicon plates for cooling operations at the beginning of casting;

[0029] (3) The crystallizer should be polished regularly, and the oil and water circuits should be checked regularly.

[0030] Furthermore, in S3, systematic monitoring and management include the following steps:

[0031] (1) Establish a temperature record system for each furnace, and record the casting temperature data of each furnace of 6061 aluminum alloy plate ingot throughout the process.

[0032] (2) Implement a multi-position collaborative responsibility mechanism and clarify the responsibilities of positions such as process director, shift leader and main operator;

[0033] (3) Establish a regular spot check and shift handover inspection mechanism.

[0034] Furthermore, this includes holding regular quality control meetings with personnel responsible for quality management, to continuously optimize process parameters and operating procedures.

[0035] Furthermore, this also includes incorporating process parameters and operating procedures into the company's "6061 Aluminum Alloy Plate Ingot Anti-Cracking Management System" as a basis for standardized production.

[0036] A process control system for preventing edge cracking in the casting of 6061 aluminum alloy slabs includes:

[0037] (1) Temperature monitoring module: used to monitor the opening temperature, the end temperature of the casting section and the water temperature in real time, and to feed back the monitoring data;

[0038] (2) Flow control module: used to precisely control the water flow and the opening of the small cooling water valve, to ensure that the water flow is stable at 260–275 m³ / h and that the opening of the small cooling water valve is at 50% scale;

[0039] (3) Liquid level detection module: used to detect the liquid level height of the crystallizer in real time to ensure that the liquid level is maintained at 7.5–8 cm from the upper edge;

[0040] (4) Job Responsibility Management Module: Used to clarify the responsibilities and authority of process supervisors, shift leaders, and main operators, and to achieve collaborative management of multiple positions;

[0041] (5) Data recording and analysis module: used to implement the temperature recording system of one furnace and one book, store various process parameter data in the casting process, and support data query and analysis.

[0042] Furthermore, the temperature monitoring module includes multiple temperature sensors, which are deployed at the casting furnace gate, at different locations at the end of the casting section, and in the cooling water circuit.

[0043] Compared with the prior art, the beneficial effects of the present invention are as follows: The method and system for controlling the anti-cracking process in the casting of 6061 aluminum alloy plate ingots have the following advantages:

[0044] 1. The cracking feedback rate has been significantly reduced: from 3.07% in the existing technology to 0.76%, effectively solving the core problem of cracking during hot rolling of 6061 aluminum alloy plates;

[0045] 2. Significantly improved economic benefits: monthly claims amount reduced by approximately RMB 95,500, waste material reduced by 64 tons, burning loss cost saved by RMB 3,840, finished product profit increased by approximately RMB 38,400, and the total monthly economic benefits generated were approximately RMB 182,500.

[0046] 3. Improved product quality and production safety: Precise control of process parameters and regular equipment maintenance make the internal structure of the slab more uniform and the quality more stable, which not only improves the yield but also reduces the production safety hazards caused by edge cracking in subsequent processes.

[0047] 4. High scalability: This invention effectively solves the problem of edge cracking in hot rolling of 6061 aluminum alloy ingots through systematic process parameter control, material improvement and job responsibility system, and is suitable for standardized promotion in aluminum alloy casting enterprises. Detailed Implementation

[0048] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0049] A method for preventing edge cracking in the casting process of 6061 aluminum alloy plate ingots employs a multi-dimensional collaborative control strategy, including three levels: precise control of process parameters, material and operation improvement, and systematic monitoring and management. Specifically, it includes:

[0050] S1 process parameter control

[0051] (1) Casting speed: Controlled at 42–44 mm / min. This speed range can ensure that the aluminum alloy melt is fully solidified in the crystallizer, avoid internal stress concentration due to excessive solidification speed, and take into account production efficiency.

[0052] (2) Casting temperature: set at 725–730°C. This temperature ensures that the aluminum alloy melt has good fluidity, which is convenient for filling the crystallizer, and also avoids the coarse grains of the ingot due to excessive temperature, which reduces the toughness of the material.

[0053] (3) Water flow control: Maintain at 260–275 m³ / h. A stable cooling water flow can ensure that the aluminum alloy ingots obtain a uniform cooling effect during solidification and prevent local cooling from being too fast and causing cracks.

[0054] (4) Water temperature control: Control at 28–33°C to avoid excessively high water temperature affecting cooling efficiency, or excessively low water temperature causing excessively fast cooling rate and stress cracks.

[0055] (5) Liquid level in the crystallizer: It should be controlled at 7.5–8 cm from the top edge. A suitable liquid level can ensure that the solidification path of the melt in the crystallizer is reasonable and reduce the impact of liquid level fluctuations on the surface quality and internal structure of the ingot.

[0056] (6) The opening of the cooling water valve on the small face is fixed at 50% and is strictly prohibited from being adjusted without authorization. This is to ensure the stable cooling intensity of the small face of the aluminum alloy plate ingot and to avoid cracking due to uneven cooling.

[0057] (7) Segmented end temperature control: The end temperature of the ingot is precisely controlled in segments according to different stages of the casting process, specifically as follows:

[0058] 0–300mm segment: 660–680°C. This stage is the initial solidification of the ingot. Controlling this temperature range can promote grain refinement.

[0059] 300–500mm section: 680–695°C, to ensure a smooth transition during solidification and reduce stress accumulation;

[0060] 500–700mm segment: 695–700°C, further optimize internal structure and improve material density;

[0061] From 700mm to the end of casting: 695–705°C, to ensure the solidification quality of the tail of the ingot and avoid cracks caused by excessively low temperature at the tail.

[0062] Material and Operation Improvements (1) Trace Element Control: Strictly control the content of Pb element in raw materials to ≤0.02%. Pb element will form a low melting point phase in aluminum alloy, which will destroy the continuity of the material and reduce its high temperature toughness. Therefore, limiting its content is one of the key measures to prevent edge cracking. (2) Cooling Method Improvement: Use small aluminum ingots instead of traditional silicon plates for initial cooling. The thermal conductivity of aluminum ingots is more compatible with 6061 aluminum alloy, and the cooling process is more stable. This can avoid the local temperature change caused by silicon plate cooling and reduce stress generation. (3) Equipment Maintenance Standards: Regularly grind the crystallizer to remove surface wear and attachments, ensure the smoothness of the inner wall of the crystallizer, reduce the frictional resistance between the ingot and the crystallizer, and avoid scratches on the surface of the ingot that cause edge cracking. At the same time, regularly check the smoothness of the oil and water circuits to ensure stable equipment operation.

[0063] S2 Systematic Monitoring and Management

[0064] (1) Establish a temperature record system for each furnace, and record key temperature data such as the start-up temperature, end temperature of each section, and water temperature of each furnace ingot throughout the process to facilitate traceability and analysis.

[0065] (2) Implement a multi-position collaborative responsibility system involving process director, shift leader, main operator, etc., and clarify the responsibilities of each position in process execution, equipment inspection, data recording, etc., to ensure that process requirements are implemented in place;

[0066] (3) Establish a regular spot check and shift handover inspection mechanism, regularly check the implementation of process requirements, equipment status and material quality, and confirm key data and equipment status during shift handover to avoid control loopholes due to job handover.

[0067] (4) Hold regular quality control meetings to summarize problems that occur during production, analyze data related to edge cracking, and continuously optimize process parameters and operating procedures.

[0068] To achieve the above-mentioned method for preventing edge cracking in the casting of 6061 aluminum alloy slabs, this invention also provides a supporting process control system, which includes the following modules:

[0069] Temperature monitoring module: It consists of multiple temperature sensors and data transmission units. The temperature sensors are deployed at different locations at the casting furnace gate, the end of the casting section, and in the cooling water circuit. It monitors the opening temperature, the end temperature of the casting section, and the water temperature in real time, and transmits the monitoring data to the data recording and analysis module. When the temperature exceeds the set range, an early warning signal is issued.

[0070] Flow control module: includes flow sensor, control valve and control unit. The flow sensor detects the water flow in the cooling water circuit in real time. The control unit automatically adjusts the opening of the control valve according to the set flow range (260–275 m³ / h) to ensure that the water flow is stable within the set range and that the opening of the small cooling water valve is at 50%.

[0071] Liquid level detection module: A liquid level sensor is installed inside the crystallizer to detect the liquid level height in real time. When the liquid level exceeds the set range of 7.5-8cm from the upper edge, it is promptly fed back to the control terminal to remind the operator to make adjustments.

[0072] Job Responsibility Management Module: This is a software system module that includes a list of responsibilities, operating procedures, and performance evaluation standards for each job position. It supports job work records, task allocation, and performance data statistics, enabling information-based collaborative management of multiple positions.

[0073] Data recording and analysis module: It has data storage, query, statistics and analysis functions. It stores relevant data for each furnace and supports data query by furnace number, date and other conditions. It can perform statistical analysis on data such as edge cracking rate and process parameter execution status, and provide data support for process optimization.

[0074] The implementation steps of the above-mentioned method for controlling edge cracking in the casting of 6061 aluminum alloy plate ingots are as follows:

[0075] The first step is to develop process standards: incorporate the above process parameters, operating procedures, and job responsibilities into the "Prevention of Edge Cracking Management System" to form standardized production documents;

[0076] The second step is to implement job responsibilities: organize training for relevant personnel to clarify the job responsibilities and operational requirements of the main operator, shift leader, process director, circulating water personnel, etc.

[0077] The third step is equipment and material control: regularly polish the crystallizer and check the oil and water circuits for unobstructed flow; strictly test the Pb content in the raw materials to ensure it is ≤0.02%; prepare small aluminum ingots for initial cooling to replace traditional silicon plates;

[0078] The fourth step is process monitoring and recording: process parameters are monitored in real time through temperature sensors, flow monitoring equipment, etc., and the main operator records relevant data according to the requirement of one book for each furnace.

[0079] Step 5: Regular inspection and improvement: Implement a regular spot check and shift handover inspection system, hold regular quality control meetings, and continuously optimize process parameters and operations based on production data and actual problems.

[0080] Example

[0081] The process control method of the present invention will be described in detail below using an actual production case of an aluminum alloy casting company.

[0082] Previously, when producing 6061 aluminum alloy ingots, the company experienced a hot-rolling edge cracking feedback rate of 3.07%, resulting in monthly claims of approximately 95,500 yuan and the generation of 64 tons of scrap, causing significant economic losses. The process control method of this invention is implemented as follows:

[0083] 1. Process Implementation

[0084] A "Crack Prevention Management System" was established, clearly stipulating that the casting speed is 43 mm / min, the initial pouring temperature is 728°C, the water flow rate is 268 m³ / h, the water temperature is controlled at 30°C, the liquid level in the crystallizer is 7.8 cm from the top edge, and the opening of the cooling water valve on the small face is fixed at 50%. The end temperature control of the casting sections is as follows: 670°C for the 0–300 mm section, 690°C for the 300–500 mm section, 698°C for the 500–700 mm section, and 700°C for the 700 mm to the end of casting. The Pb content in the raw materials is controlled at 0.015%. Small aluminum ingots are used to replace silicon plates for initial cooling. The responsibilities of the process supervisor, shift leader, and main operator are clearly defined.

[0085] Job training: Organize training on the system for main operators, shift leaders, process directors, circulating water personnel, etc., to ensure that all personnel are familiar with the process parameter requirements, operating procedures and their own responsibilities;

[0086] Equipment and material preparation: The existing crystallizer was thoroughly polished, and the oil and water circuits were checked to ensure they were unobstructed; raw materials that met the Pb content requirements were purchased, and the Pb content was tested to be 0.015%; sufficient small aluminum ingots were prepared for initial cooling.

[0087] Process execution: During the casting process, the main operator monitors the opening temperature, end temperature of each section, and water temperature in real time through the temperature monitoring module, confirms the water flow rate through the flow control module, and observes the liquid level height in the crystallizer through the liquid level detection module to ensure that all parameters meet the set requirements; in accordance with the requirement of one record per furnace, the relevant data for each furnace are recorded in detail; during shift handover, the execution status of process parameters, equipment status, and data records are handed over and confirmed.

[0088] Regular inspections and improvements: A quality control meeting is held every Wednesday to summarize the production data of the week, analyze edge cracking, and continuously optimize process parameters and operations.

[0089] 2. System Operation

[0090] The company uses the process control system of this invention. The temperature monitoring module's sensors collect real-time data on the start-up temperature, end-of-segment temperature, and water temperature. When the start-up temperature reaches 732°C, the system issues a timely warning, and operators quickly adjust the furnace temperature to prevent the production of defective ingots. The flow control module automatically adjusts the valve opening of the cooling water circuit to ensure a stable water flow rate of approximately 268 m³ / h. The liquid level detection module provides real-time feedback on the crystallizer liquid level, allowing operators to adjust the molten liquid injection volume accordingly. The job responsibility management module digitizes the work records of each position, facilitating supervision and inspection by the process supervisor. The data recording and analysis module stores relevant data for each furnace, providing data support for process optimization during quality control circle meetings.

[0091] 3. Implementation Results

[0092] After three months of trial operation, the cracking feedback rate of the company's 6061 aluminum alloy ingots has steadily decreased from 3.07% to 0.76%; the monthly claim amount has been reduced by approximately 95,500 yuan, waste material has been reduced by 64 tons, burning loss costs have been saved by 3,840 yuan, and finished product profits have increased by approximately 38,400 yuan, generating a total monthly economic benefit of approximately 182,500 yuan; the quality of the ingots has been significantly improved.

[0093] The above are merely embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for controlling edge cracking during casting of 6061 aluminum alloy plate ingots, characterized in that, Includes the following steps: S1: Process parameter control, which coordinates the control of parameters during the casting process. These parameters include casting speed, initial pouring temperature, water flow rate, water temperature, crystallizer liquid level height, and small-face cooling water valve opening. S2: Material and operational improvements, control of trace element content in raw materials, improvement of cooling methods and equipment maintenance standards; S3: Systematic monitoring and management, standardizing management systems and job responsibilities.

2. The method for controlling edge cracking during casting of 6061 aluminum alloy plate ingots according to claim 1, characterized in that, In S1, process parameter control includes the following steps: (1) Control the casting speed to 42–44 mm / min; (2) Control the initial pouring temperature to 725–730°C; (3) Control the liquid level in the crystallizer to be 7.5–8 cm from the top edge; (4) Control the water flow rate to 260–275 m³ / h; (5) Control the water temperature to 28–33°C; (6) The opening of the small cooling water valve should be controlled at 50% of the scale, and it is strictly forbidden to adjust it privately.

3. The method for controlling edge cracking during casting of 6061 aluminum alloy plate ingots according to claim 2, characterized in that, This also includes controlling the temperature at the end of the casting section, specifically: The temperature of the casting end section (0–300 mm) is controlled at 660–680°C. The temperature of the casting end section (300–500 mm) is controlled at 680–695°C. The temperature of the casting end section (500–700 mm) is controlled at 695–700°C. The temperature is controlled at 695–705°C from the end of casting (700mm from the casting tip) to the end of casting.

4. The method for controlling edge cracking during casting of 6061 aluminum alloy plate ingots according to claim 1, characterized in that, In S2, material and operational improvements include the following steps: (1) The lead content in the alloy shall not exceed 0.02%; (2) Use aluminum ingots instead of silicon plates for cooling operations at the beginning of casting; (3) The crystallizer should be polished regularly, and the oil and water circuits should be checked regularly.

5. The method for controlling edge cracking during casting of 6061 aluminum alloy plate ingots according to claim 1, characterized in that, In S3, systematic monitoring and management include the following steps: (1) Establish a temperature record system for each furnace, and record the casting temperature data of each furnace of 6061 aluminum alloy plate ingot throughout the process. (2) Implement a multi-position collaborative responsibility mechanism and clarify the responsibilities of positions such as process director, shift leader and main operator; (3) Establish a regular spot check and shift handover inspection mechanism.

6. The method for controlling edge cracking during casting of 6061 aluminum alloy plate ingots according to claim 1, characterized in that, This also includes holding regular quality control meetings, with participants being personnel responsible for quality management, to continuously optimize process parameters and operating procedures.

7. The method for controlling edge cracking during casting of 6061 aluminum alloy plate ingots according to claim 1, characterized in that, This also includes incorporating process parameters and operating procedures into the company's "6061 Aluminum Alloy Plate Ingot Anti-Cracking Management System" as a basis for standardized production.

8. A control system based on the method for preventing edge cracking in the casting of 6061 aluminum alloy plate ingots according to any one of claims 1-7, characterized in that, include: (1) Temperature monitoring module: used to monitor the opening temperature, the end temperature of the casting section and the water temperature in real time, and to feed back the monitoring data; (2) Flow control module: used to precisely control the water flow and the opening of the small cooling water valve, to ensure that the water flow is stable at 260–275 m³ / h and that the opening of the small cooling water valve is at 50% scale; (3) Liquid level detection module: used to detect the liquid level height of the crystallizer in real time to ensure that the liquid level is maintained at 7.5–8 cm from the upper edge; (4) Job Responsibility Management Module: Used to clarify the responsibilities and authority of process supervisors, shift leaders, and main operators, and to achieve collaborative management of multiple positions; (5) Data recording and analysis module: used to implement the temperature recording system of one furnace and one book, store various process parameter data in the casting process, and support data query and analysis.

9. A process control system for preventing edge cracking in the casting of 6061 aluminum alloy plate ingots according to claim 8, characterized in that, The temperature monitoring module includes multiple temperature sensors, which are deployed at the casting furnace gate, at different locations at the end of the casting section, and in the cooling water circuit.