Spheroidizing annealing method for SWRCH35K cold forging steel

Abstract

The invention relates to the technical field of metal heat treatment processes, and discloses a spheroidizing annealing method for SWRCH35K cold forging steel, which comprises the following steps: step 1, quality detection and pretreatment of the SWRCH35K cold forging steel: appearance and internal quality detection is carried out on the SWRCH35K cold forging steel; 2, rapid heating is conducted, specifically, the SWRCH35K cold forging steel is heated through the laser heating technology; 3, heat preservation treatment, wherein after the laser heating temperature reaches the preset temperature, the temperature is kept for a period of time; 4, rapid cooling is conducted, specifically, argon is used as a rapid cooling medium, and the SWRCH35K cold forging steel is cooled; 5, automatic control, wherein an automatic production line is established, and automatic control over the whole process from heating, heat preservation to cooling is achieved; and 6, intelligent monitoring is conducted, specifically, temperature and flow parameters in the annealing process are monitored and analyzed in real time through a sensor and a data analysis technology, and through the processing steps, the problems that an existing annealing method is long in processing time and high in cost are solved.

Description

Technical Field

[0001] The invention relates to the technical field of metal heat treatment technology, in particular to a spheroidizing annealing method for SWRCH35K cold heading steel. Background Art

[0002] Heat treatment is a key means to improve the mechanical properties, processing properties and microstructure of metal SWRCH35K cold heading steel. By controlling the heating temperature, holding time and cooling rate, the hardness, toughness and strength of SWRCH35K cold heading steel can be adjusted. Cold heading steel is mainly used to produce high-strength fasteners such as bolts and nuts, which are widely used in the automotive, machinery and other industries. Therefore, it is crucial to ensure that it has good plasticity and formability. Although the existing annealing methods can improve the performance of SWRCH35K cold heading steel to a certain extent, they often have problems such as long processing time and high cost. Summary of the invention

[0003] In view of the deficiencies in the prior art, the present invention provides a spheroidizing annealing method for SWRCH35K cold heading steel, which has the advantages of short processing time and low cost, and solves the problems of long processing time and high cost in the prior annealing method.

[0004] To achieve the above object, the present invention provides the following technical solution: a spheroidizing annealing method for SWRCH35K cold heading steel, comprising the following steps: Step 1: Quality inspection and pretreatment of SWRCH35K cold heading steel: Perform appearance and internal quality inspection on SWRCH35K cold heading steel; Step 2: Rapid heating: Use laser heating technology to heat the SWRCH35K cold heading steel; Step 3: Heat preservation: After the laser heating temperature reaches the preset temperature, keep it at this temperature for a period of time; Step 4: Rapid cooling: Use argon as a rapid cooling medium to cool the SWRCH35K cold heading steel; Step 5: Automated control: Establish an automated production line to achieve automated control of the entire process from heating, insulation to cooling; Step 6. Intelligent monitoring: Use sensors and data analysis technology to monitor and analyze the temperature and flow parameters during the annealing process in real time.

[0005] Preferably, in the step 1, the quality inspection of SWRCH35K cold heading steel uses a high-precision camera and image processing technology to automatically inspect the surface of the SWRCH35K cold heading steel. When the scratch depth is detected to be <0.1mm, it is qualified data. When the scratch depth is detected to be ≥0.1mm, unqualified products are automatically removed by a robotic arm or a conveyor belt. The qualified internal quality inspection of the SWRCH35K cold heading steel includes chemical composition content, impurity content, mechanical properties, cold forging test and decarburization layer inspection, all of which are qualified.

[0006] Preferably, the pretreatment process of step 1 is: S1.1, pickling: put SWRCH35K cold heading steel into 5% sulfuric acid solution and soak for 1.5-2.0h; S1.2 Neutralization and water washing: After pickling, the SWRCH35K cold heading steel is placed in a 10% sodium hydroxide solution for 30 minutes to neutralize the excess sulfuric acid solution, and then washed with running water for 10 minutes.

[0007] S1.3, Drying: Place the cleaned SWRCH35K cold heading steel into a hot air drying furnace for drying, and control the temperature between 85-100℃.

[0008] Preferably, the laser heating process in step 2: S2.1. Select CO2 laser to heat SWRCH35K cold heading steel, set the wavelength of the laser to 10.6 μm, adjust the power between 8 kW and 10 kW, the spot size between 2-4 mm, and the scanning speed between 1-1.2 MHz; S2.2. Place the SWRCH35K cold heading steel in the working area of ​​the CO2 laser, adjust the position, and start the laser to ensure that the laser beam can evenly irradiate the surface of the SWRCH35K cold heading steel. Rapidly heat the SWRCH35K cold heading steel according to the preset parameters of S2.1. The high energy density of the laser will quickly increase the surface temperature of the SWRCH35K cold heading steel. At the same time, use an infrared thermometer to monitor the temperature changes on the surface of the SWRCH35K cold heading steel in real time.

[0009] Preferably, in the step three, the heat preservation treatment is performed by maintaining the temperature at a preset temperature of 700-750° C. for 3-5 hours after the laser heating temperature reaches the preset temperature of 700-750° C.

[0010] Preferably, in step 4, argon is used as a rapid cooling medium, an argon content greater than 99.99% is used, and the flow rate is set to 100-120 L / min, and the cooling time is set to 5% of the total manufacturing time of SWRCH35K cold heading steel. After the argon is circulated through the cold heading steel, the circulating argon is recovered.

[0011] Preferably, the automated control in step five is to establish an automated production line from the beginning to achieve automated control of the entire process from heating, heat preservation to cooling.

[0012] Preferably, the automatic control is connected to the automatic control interface of the pretreatment process through a network cable, and an automatic pickling program is set on the automatic control interface, which can adjust the concentration of sulfuric acid solution and the soaking time, set the neutralization and water washing program, can automatically adjust the concentration of sodium hydroxide solution and the neutralization time, and set the automatic water cleaning time, drying time and temperature.

[0013] Preferably, the automated control connects the CO2 laser to the control interface by adding a network cable facility during the laser heating process, sets the wavelength, power, spot size and scanning speed of the laser through the control interface, and connects the transmission department to transmit the SWRCH35K cold heading steel to the working area of ​​the CO2 laser, automatically adjusts the position and monitors the temperature change of the cold heading steel in real time.

[0014] Preferably, the intelligent monitoring in step six is ​​as follows: the temperature of the SWRCH35K cold heading steel during the insulation treatment is monitored in real time by a temperature sensor and a monitoring device, and the flow rate of argon gas during the cooling process is monitored by a flow controller and a monitoring device.

[0015] Compared with the prior art, the present invention provides a spheroidizing annealing method for SWRCH35K cold heading steel, which has the following beneficial effects: 1. The present invention can quickly and accurately identify the depth of tiny scratches on the surface of SWRCH35K cold heading steel by adopting high-precision cameras and advanced image processing technology. This method can not only improve the detection efficiency, but also reduce human errors, so that the detection results are accurate. When the scratch depth is less than 0.1mm monitored in the detection method, it will be automatically judged as qualified data, and unqualified products can be quickly eliminated. The process is fully automated and does not require human intervention, which can improve production efficiency. At the same time, it also prevents unqualified products from flowing into the next production link to ensure the overall product quality.

[0016] 2. The present invention adds 10% of sodium hydroxide solution for neutralization after pickling, which helps to neutralize excess sulfuric acid solution. The entire pretreatment process is connected to the automatic control interface through a network cable to achieve the selection of reagents. However, in Comparative Example 2, after pickling, running clean water is directly used for 10 minutes of washing. This process does not perform neutralization treatment, which will cause acidic substances to remain on the surface of the steel, affecting subsequent processing and use. No automated process is set, which will lead to untimely or excessive acid addition.

[0017] 3. The present invention can ensure the purity of the cooling medium by using high-purity argon (such as 99.99%) to avoid the introduction of other impurities that have an adverse effect on the performance of the steel. High-purity argon helps to improve the cooling effect and efficiency. In the spheroidizing annealing process of SWRCH35K cold heading steel, selecting an argon flow range of 100-120L / min can provide a fast cooling rate, which helps to quickly reduce the temperature of the steel and avoid the generation of thermal stress. At the same time, too high a flow rate can also cause a large temperature gradient inside the steel, thereby inducing thermal stress. The cooling time is set to 5% of the total manufacturing time of SWRCH35K cold heading steel. This time ratio ensures that the steel can be quickly and evenly cooled to room temperature while taking into account the production efficiency requirements. Finally, the circulating argon is recycled, which helps to control the cost of the entire process. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a step diagram of the method of the present invention. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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 creative work are within the scope of protection of the present invention.

[0020] See also Figure 1 , a spheroidizing annealing method for SWRCH35K cold heading steel, comprising the following steps: Step 1: Quality inspection and pretreatment of SWRCH35K cold heading steel: Perform appearance and internal quality inspection on SWRCH35K cold heading steel, and perform pretreatment after meeting the annealing requirements to remove surface impurities and oxidized substances; Step 2: Rapid heating: Use laser heating technology to heat the SWRCH35K cold heading steel. Laser heating uses its high energy density and precise control capabilities to achieve rapid and uniform heating. Step 3: Insulation treatment: After the laser heating temperature reaches the preset temperature, it is maintained at this temperature for a period of time to ensure that the carbides inside the SWRCH35K cold heading steel are fully spheroidized. This step usually needs to be performed at a specific temperature to avoid overheating or uneven heating. Step 4: Rapid cooling: Use argon as a rapid cooling medium to cool the SWRCH35K cold heading steel. Rapid cooling can effectively avoid the generation of thermal stress and maintain the stability of the microstructure of the SWRCH35K cold heading steel. Step 5: Automated control: Establish an automated production line to achieve automated control of the entire process from heating, heat preservation to cooling. This not only reduces manual operations, but also improves production efficiency and product quality stability; Step 6: Intelligent monitoring: Use sensors and data analysis technology to monitor and analyze the temperature and flow parameters during the annealing process in real time. Optimize annealing process parameters through intelligent algorithms to achieve precise control and predictive maintenance, further improving annealing efficiency and quality.

[0021] Specifically, the automated control in step five: starting from establishing an automated production line, to achieve automated control of the entire process from heating, insulation to cooling.

[0022] Specifically, in step six, intelligent monitoring is performed: the temperature of the SWRCH35K cold heading steel during the insulation treatment is monitored in real time by a temperature sensor and a monitoring device, and the flow rate of argon gas during the cooling process is monitored by a flow controller and a monitoring device.

[0023] Example 1 For the quality inspection of SWRCH35K cold heading steel, a high-precision camera and image processing technology are used to automatically inspect the surface of SWRCH35K cold heading steel. When the scratch depth is detected to be <0.1mm, it is qualified data. When the scratch depth is detected to be ≥0.1mm, the unqualified products are automatically removed by a robotic arm or a conveyor belt. The qualified internal quality inspection of SWRCH35K cold heading steel includes chemical composition content, impurity content, mechanical properties, cold forging test and decarburization layer inspection. The qualified SWRCH35K cold heading steel is continued to be conveyed to the next step.

[0024] Comparative Example 1 For the quality inspection of SWRCH35K cold heading steel, a magnifying glass is used to automatically inspect the surface of SWRCH35K cold heading steel. The qualified internal quality inspection of SWRCH35K cold heading steel includes chemical composition content, impurity content, mechanical properties, cold forging test and decarburization layer inspection. The qualified SWRCH35K cold heading steel is then transferred to the next step.

[0025] In Example 1, a high-precision camera and advanced image processing technology are used to quickly and accurately identify the depth of tiny scratches on the surface of SWRCH35K cold heading steel. This method can not only improve the detection efficiency, but also reduce human errors, so that the detection results are accurate. When the scratch depth is less than 0.1 mm detected in the detection method, it will be automatically determined as qualified data, and unqualified products can be quickly removed. The process is fully automated and does not require human intervention. It can improve production efficiency and also prevent unqualified products from flowing into the next production link to ensure the overall product quality. In Example 1, a traditional magnifying glass is used for surface inspection. Although this method is simple and easy, it is inefficient and easily affected by human factors. In addition, manual inspection with a magnifying glass cannot achieve the function of automatically removing unqualified products.

[0026] Example 2 This embodiment relates to a pretreatment method for SWRCH35K cold heading steel, comprising the following steps: S1.1, pickling: put SWRCH35K cold heading steel into 5% sulfuric acid solution and soak for 1.5-2.0h to remove rust, oxide scale and impurities on the surface of original SWRCH35K cold heading steel; S1.2 Neutralization and water washing: After pickling, put the SWRCH35K cold heading steel into a 10% sodium hydroxide solution for 30 minutes to neutralize the excess sulfuric acid solution, and then wash it with running water for 10 minutes to ensure the surface is clean.

[0027] S1.3, Drying: Place the cleaned SWRCH35K cold heading steel into a hot air drying furnace for drying, and control the temperature between 85-100℃ to ensure that there is no moisture on the surface.

[0028] In this embodiment 2, the automatic control interface of the pretreatment process is connected through a network cable, and an automatic pickling program is set on the automatic control interface. The concentration of sulfuric acid solution and the soaking time can be adjusted, and the neutralization and water washing programs are set. The concentration of sodium hydroxide solution and the neutralization time can be automatically adjusted, and the automatic water cleaning time, drying time and temperature are set. This process can realize automatic control of the amount of reagents in the pretreatment process of SWRCH35K cold heading steel, thereby improving production efficiency and avoiding waste of reagents.

[0029] Comparative Example 2 This comparative example 2 relates to a pretreatment method for SWRCH35K cold heading steel, comprising the following steps: S1.1, pickling: put SWRCH35K cold heading steel into 5% sulfuric acid solution and soak for 1.5-2.0h to remove rust, oxide scale and impurities on the surface of original SWRCH35K cold heading steel; S1.2 Neutralization and water washing: After pickling, rinse with running water for 10 minutes to ensure the surface is clean.

[0030] S1.3, Drying: Place the cleaned SWRCH35K cold heading steel into a hot air drying furnace for drying, and control the temperature between 85-100℃ to ensure that there is no moisture on the surface.

[0031] After pickling in Example 2, a neutralization treatment with 10% sodium hydroxide solution is added to neutralize excess sulfuric acid solution, and the entire pretreatment process is connected to an automatic control interface via a network cable to achieve the selection of reagents. However, after pickling in Comparative Example 2, running clean water is directly used for 10 minutes of washing. This process does not involve neutralization treatment, which will result in residual acidic substances on the surface of the steel, affecting subsequent processing and use. No automated process is set, which will result in untimely or excessive acid addition.

[0032] Example 3 This embodiment relates to a laser heating method for SWRCH35K cold heading steel, comprising the following steps: S2.1. Select CO2 laser to heat SWRCH35K cold heading steel, set the wavelength of the laser to 10.6 μm, adjust the power between 8 kW and 10 kW, the spot size between 2-4 mm, and the scanning speed between 1-1.2 MHz; S2.2. Place the SWRCH35K cold heading steel in the working area of ​​the CO2 laser, adjust the position, and start the laser to ensure that the laser beam can evenly irradiate the surface of the SWRCH35K cold heading steel. Rapidly heat the SWRCH35K cold heading steel according to the preset parameters of S2.1. The high energy density of the laser will quickly increase the surface temperature of the SWRCH35K cold heading steel. At the same time, use an infrared thermometer to monitor the temperature changes on the surface of the SWRCH35K cold heading steel in real time to ensure that the heating process is under control.

[0033] In this embodiment 3, the automatic control interface of the laser heating process is connected through a network cable, and the wavelength, power, spot size and scanning speed of the laser are set on the automatic control interface, and the transmission department is connected to transmit the SWRCH35K cold heading steel to the working area of ​​the CO2 laser, and the position is automatically adjusted and the temperature change of the cold heading steel is monitored in real time. In this way, the automatic control of the laser heating process of the SWRCH35K cold heading steel can be realized, and the production efficiency and product quality can be improved.

[0034] Comparative Example 3 This comparative example 3 relates to a resistance heating method for SWRCH35K cold heading steel, comprising the following steps: A resistance furnace was selected to heat the SWRCH35K cold heading steel, and the set temperature was 700-750℃.

[0035] In Example 3, the high energy density laser beam of the CO2 laser can quickly increase the surface temperature of the SWRCH35K cold heading steel, while the resistance heating in Comparative Example 3 takes a long time to reach the required temperature, and due to the limitation of the heat transfer method, it will cause uneven temperature inside the steel.

[0036] Example 4 Insulation treatment: After the laser heating temperature reaches the preset temperature of 700~750℃, it is maintained at this temperature for 3-5h. The temperature of SWRCH35K cold heading steel during the insulation treatment is monitored in real time by temperature sensors and monitoring equipment.

[0037] Comparative Example 4 Heat preservation treatment: After the laser heating temperature reaches the preset temperature of 700~750℃, keep it at this temperature for 3-5h.

[0038] In Example 4, by introducing real-time monitoring means, precise control and stable maintenance of the temperature during the insulation treatment process are achieved, which helps to improve product quality and production efficiency. However, due to the lack of real-time monitoring means in Comparative Example 4, there is an inability to monitor the changes in steel temperature in real time, thereby failing to accurately control the temperature, resulting in unstable product quality.

[0039] Example 5 Argon is used as a rapid cooling medium with an argon content greater than 99.99%. The flow rate is set to 100-120 L / min, and the cooling time is set to 5% of the total manufacturing time of SWRCH35K cold heading steel. After the argon is circulated through the cold heading steel, the circulating argon is recovered, and the flow rate of the argon during the cooling process is monitored by a flow controller and monitoring equipment.

[0040] Comparative Example 5 Use argon as the rapid cooling medium, use argon with a content greater than 99.99%, and set the flow rate to 100-120L / min.

[0041] Example 5 Using high-purity argon (such as 99.99%) can ensure the purity of the cooling medium to avoid the introduction of other impurities that may adversely affect the performance of the steel. High-purity argon helps to improve the cooling effect and efficiency. In the spheroidizing annealing process of SWRCH35K cold heading steel, selecting an argon flow range of 100-120L / min can provide a fast cooling rate, which helps to quickly reduce the temperature of the steel and avoid the generation of thermal stress. At the same time, too high a flow rate can also cause a large temperature gradient inside the steel, thereby causing thermal stress. The cooling time is set to the total amount of SWRCH35K cold heading steel. 5% of the manufacturing time. This time ratio ensures that the steel can be quickly and evenly cooled to room temperature while taking into account the needs of production efficiency. Finally, the circulating argon is recovered to control the cost of the process. Due to the lack of real-time monitoring means, the rapid cooling method in Example 5 has the problems of inaccurate argon flow control and unstable cooling effect. During the cooling process, the fluctuation of argon flow rate will lead to inconsistent cooling speed, thereby affecting the quality of the final product. The lack of real-time monitoring also increases the risk and uncertainty in the production process. The lack of argon recovery process also increases the cost of the chemical process.

[0042] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A spheroidizing annealing method for SWRCH35K cold heading steel, characterized in that: The following steps are involved: Step 1: Quality inspection and pretreatment of SWRCH35K cold heading steel: Perform appearance and internal quality inspection on SWRCH35K cold heading steel; Step 2: Rapid heating: Use laser heating technology to heat the SWRCH35K cold heading steel; Step 3: Heat preservation: After the laser heating temperature reaches the preset temperature, keep it at this temperature for a period of time; Step 4: Rapid cooling: Use argon as a rapid cooling medium to cool the SWRCH35K cold heading steel; Step 5: Automated control: Establish an automated production line to achieve automated control of the entire process from heating, insulation to cooling; Step 6. Intelligent monitoring: Use sensors and data analysis technology to monitor and analyze the temperature and flow parameters during the annealing process in real time.

2. The spheroidizing annealing method of SWRCH35K cold heading steel according to claim 1, characterized in that: In the step 1, the quality inspection of SWRCH35K cold heading steel uses a high-precision camera and image processing technology to automatically inspect the surface of SWRCH35K cold heading steel. When the scratch depth is detected to be less than 0.1mm, it is qualified data. When the scratch depth is detected to be ≥0.1mm, unqualified products are automatically removed by a robotic arm or a conveyor belt. The qualified internal quality inspection of SWRCH35K cold heading steel includes chemical composition content, impurity content, mechanical properties, cold forging test and decarburization layer inspection, all of which are qualified.

3. The spheroidizing annealing method of SWRCH35K cold heading steel according to claim 1, characterized in that: The pretreatment process of step 1 is as follows: S1.1, pickling: put SWRCH35K cold heading steel into 5% sulfuric acid solution and soak for 1.5-2.0h; S1.2, Neutralization and water washing: After pickling, put the SWRCH35K cold heading steel into a 10% sodium hydroxide solution for 30 minutes to neutralize the excess sulfuric acid solution, and then wash it with running water for 10 minutes; S1.3, Drying: Place the cleaned SWRCH35K cold heading steel into a hot air drying furnace for drying, and control the temperature between 85-100℃.

4. The spheroidizing annealing method of SWRCH35K cold heading steel according to claim 1, characterized in that: Laser heating process in step 2: S2.

1. Select CO2 laser to heat SWRCH35K cold heading steel, set the wavelength of the laser to 10.6 μm, adjust the power between 8 kW and 10 kW, the spot size between 2-4 mm, and the scanning speed between 1-1.2 MHz; S2.

2. Place the SWRCH35K cold heading steel in the working area of ​​the CO2 laser, adjust the position, and start the laser to ensure that the laser beam can evenly irradiate the surface of the SWRCH35K cold heading steel. Rapidly heat the SWRCH35K cold heading steel according to the preset parameters of S2.

1. The high energy density of the laser will quickly increase the surface temperature of the SWRCH35K cold heading steel. At the same time, use an infrared thermometer to monitor the temperature changes on the surface of the SWRCH35K cold heading steel in real time.

5. The spheroidizing annealing method of SWRCH35K cold heading steel according to claim 1, characterized in that: In the step 3, the heat preservation treatment is as follows: after the laser heating temperature reaches a preset temperature of 700-750° C., the temperature is maintained for 3-5 hours.

6. The spheroidizing annealing method of SWRCH35K cold heading steel according to claim 1, characterized in that: In the step 4, argon is used as a rapid cooling medium, and the argon content is greater than 99.99%. The flow rate is set to 100-120 L / min, and the cooling time is set to 5% of the total manufacturing time of SWRCH35K cold heading steel. After the argon is circulated through the cold heading steel, the circulating argon is recovered.

7. The spheroidizing annealing method of SWRCH35K cold heading steel according to claim 1, characterized in that: The automated control in step 5: from the beginning of establishing an automated production line, realize automated control of the entire process from heating, heat preservation to cooling.

8. The spheroidizing annealing method of SWRCH35K cold heading steel according to claim 7, characterized in that: The automatic control is connected to the automatic control interface of the pretreatment process through a network cable, and an automatic pickling program is set on the automatic control interface, the concentration of sulfuric acid solution and the soaking time are adjusted, the neutralization and water washing programs are set, the concentration of sodium hydroxide solution and the neutralization time are automatically adjusted, and the automatic water cleaning time, drying time and temperature are set.

9. The spheroidizing annealing method of SWRCH35K cold heading steel according to claim 7, characterized in that: The automatic control adds a network cable facility during the laser heating process, connects the CO2 laser to the control interface, sets the wavelength, power, spot size and scanning speed of the laser through the control interface, and connects the transmission department to transmit the SWRCH35K cold heading steel to the working area of ​​the CO2 laser, automatically adjusts the position and monitors the temperature change of the cold heading steel in real time.

10. The spheroidizing annealing method of SWRCH35K cold heading steel according to claim 9, characterized in that: The intelligent monitoring in step six: the temperature of the SWRCH35K cold heading steel during the insulation treatment is monitored in real time by a temperature sensor and a monitoring device, and the flow rate of argon gas during the cooling process is monitored by a flow controller and a monitoring device.

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