Method for producing copper-containing antibacterial martensitic stainless steel black coil by steckel mill

Abstract

The invention relates to the technical field of steel rolling production, in particular to a method for producing a copper-containing antibacterial martensitic stainless steel black coil through a steekle mill, and solves the problems that in the current copper-containing antibacterial martensitic stainless steel rolling process, steel coil edge cracking, peeling and other defects are prone to occurring. The method mainly comprises the working procedures of plate blank preheating, heating, descaling, rough rolling, finish rolling, curling, annealing and the like, and the hot-rolled black coil with excellent quality is finally rolled by setting the heating temperature, the descaling water pressure and speed, the rough rolling pass compression ratio and the finish rolling pass compression ratio and controlling the annealing temperature. The defects of steel coil edge cracking, surface peeling and the like occurring in the copper-containing antibacterial martensitic stainless steel preparation process are effectively eliminated, the plate width and large coil plate thickness range produced through rolling of the copper-containing antibacterial martensitic stainless steel is further widened, and therefore the overall production efficiency and quality of the copper-containing antibacterial martensitic stainless steel are greatly improved.

Description

Technical Field

[0001] The invention relates to the technical field of steel rolling production, and in particular to a method for producing copper-containing antibacterial martensitic stainless steel black coils by a Steckel rolling mill. Background Art

[0002] Martensitic stainless steel is a type of stainless steel whose properties are adjusted by heat treatment. After heat treatment, it has good rust resistance and hardness and is widely used in the kitchen knife industry. At present, kitchen knife steel uses a large amount of medium-high carbon martensitic stainless steel such as 30Cr13 and 40Cr13. However, with people's increasing attention to health in recent years, antibacterial materials have begun to develop gradually. Some martensitic antibacterial material brands have appeared at home and abroad and applied to the kitchen knife industry, increasing its antibacterial properties and playing a positive role in people's health. Although copper-containing martensitic stainless steel has been applied to kitchen knives, there are not many large-scale industrial mass production applications, and most of them are small-scale production processes using ingot forging methods. At the same time, hot working is only one step in the process. There is a lack of specific parameter control requirements for the thermal process of copper-containing martensitic stainless steel, which ultimately leads to poor process control in the production process, and it is very easy to have defects such as peeling and edge cracking. Summary of the invention

[0003] The invention provides a method for producing copper-containing antibacterial martensitic stainless steel black coils by a furnace coil rolling mill, so as to solve the defects such as steel coil edge cracking and peeling that are very likely to occur during the rolling process of the copper-containing antibacterial martensitic stainless steel in the above background.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions: A method for producing copper-containing antibacterial martensitic stainless steel black coils by a Steckel rolling mill comprises the following steps: Step 1, slab heating: send the 220mm thick slab cut by continuous casting into the preheating furnace for preheating, the furnace temperature is 500℃-600℃, and the slab is sent into the heating furnace for heating and insulation, the heating temperature is 1000℃-1050℃, and the heating rate is 3℃ / min.

[0005] Step 2: Surface descaling: After the slab comes out of the heating furnace, it enters the descaling machine and is descaled with high-pressure water. The water pressure is ≥250bar and the descaling rate is 2m / s.

[0006] Step 3, rough rolling: the descaled slab is subjected to intermediate rolling, with 5 passes of reduction, the reduction rates of which are 40%-45%, 30%-35%, 30%-35%, 20%-25% and 20%-25% respectively, and the rolling speed is 5 m / s.

[0007] Step 4, finishing rolling: the intermediate billet after rough rolling is finish rolled, and the reduction rates are 20%-40%, 15%-30%, 15%-30%, 15%-30%, 15%-30%, 15%-30%, 15%-30% and 10%-20% respectively, and the rolling speed is 9m / s.

[0008] Step 5: Coiling: After finishing rolling, the steel strip is rapidly coiled at a coiling speed of 2m / s-7m / s and a coiling temperature of 600℃-700℃.

[0009] Step 6, annealing: after the coil pile is cooled to 300℃-400℃ after coiling off the line, the hot coil is directly loaded into the hydrogen bell-type furnace for annealing at 820℃-850℃ and the annealing holding time is 10h-15h. Then it is slowly cooled to 200℃-250℃ and then taken out of the furnace. After the black coil is taken out of the furnace, it can be packaged after cooling to room temperature.

[0010] Furthermore, in step 1, the slab is kept warm for 150-200 minutes in the preheating furnace, and for 150-180 minutes in the heating furnace.

[0011] Furthermore, the thickness of the intermediate billet after rough rolling in step 3 is 25 mm-40 mm.

[0012] Furthermore, the black coil after being fired in step 6 has a width of 1000 mm-1530 mm and a thickness of 3 mm-12 mm.

[0013] The present invention has the following beneficial effects: The present invention provides a method for producing copper-containing antibacterial martensitic stainless steel black coils by a furnace coil rolling mill, which mainly includes the processes of slab preheating, heating, descaling, rough rolling, finish rolling, curling and annealing. By setting the heating temperature, descaling water pressure and rate, the compression ratio of rough rolling and finish rolling passes and controlling the annealing temperature, high-quality hot-rolled black coils are finally rolled out, and defects such as steel coil edge cracks and surface peeling that occur in the process of preparing copper-containing antibacterial martensitic stainless steel are effectively eliminated, and the plate width and large coil thickness range of the copper-containing antibacterial martensitic stainless steel rolling production are further improved, thereby greatly improving the overall production efficiency and quality of the copper-containing antibacterial martensitic stainless steel, and solving the problem that defects such as steel coil edge cracks and peeling are very likely to occur in the current rolling process of copper-containing antibacterial martensitic stainless steel. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the appearance of the rolled edge of the copper-containing antibacterial martensitic stainless steel in the present invention.

[0015] Figure 2 It is a schematic diagram of the surface appearance of the copper-containing antibacterial martensitic stainless steel coil after pickling after rolling in the present invention. DETAILED DESCRIPTION

[0016] The present invention will be further described below in conjunction with specific embodiments.

[0017] Example 1 A method for producing copper-containing antibacterial martensitic stainless steel black coils by a Steckel rolling mill comprises the following steps: Step 1, slab heating: send the 220mm thick slab cut by continuous casting into the preheating furnace for preheating, the furnace temperature is 500℃, and the holding time is 150min; the preheated slab is sent to the heating furnace for heating and insulation, the insulation temperature is 1000℃, the heating rate is 3℃ / min, and the insulation time is 150min.

[0018] Step 2: Surface descaling: After leaving the furnace, the slab enters the descaling machine and is descaled using high-pressure water. The water pressure is 250 bar and the descaling rate is 2 m / s.

[0019] Step 3, rough rolling: the descaled slab is subjected to intermediate rolling, with 5 passes of reduction, and the reduction rates are 40%, 30%, 30%, 20%, and 20% respectively, and the rolling speed is 5 m / s, until the intermediate slab thickness is 25 mm.

[0020] Step 4, finishing rolling: the intermediate billet thickened by rough rolling is subjected to finishing rolling, with 7 passes of reduction, and the reduction rates are 20%, 15%, 15%, 15%, 15%, 15%, 10% respectively, and the rolling speed is 9 m / s, and finally rolled into a finished product with a thickness of 3 mm.

[0021] Step 5: Curling: After rolling, the steel strip is rapidly curled at a speed of 2 m / s and a temperature of 600°C.

[0022] Step 6, annealing: After the coils are cooled to 300°C after leaving the production line, the hot coils are directly put into a bell-type furnace for annealing at 820°C. After annealing and holding for 15 hours, they are slowly cooled to 200°C and taken out of the furnace. After being taken out of the furnace, the coils are cooled to room temperature and then packaged.

[0023] Example 2 A method for producing copper-containing antibacterial martensitic stainless steel black coils by a Steckel rolling mill comprises the following steps: Step 1, slab heating: send the 220mm thick slab cut by continuous casting into the preheating furnace for preheating, the furnace temperature is 550℃, the holding time is 180min, the preheated slab is sent to the heating furnace for heating and insulation, the insulation temperature is 1030℃, the heating rate is 3℃ / min, and the insulation time is 170min.

[0024] Step 2: Surface descaling: After leaving the furnace, the slab enters the descaling machine and is descaled using high-pressure water. The water pressure is 260 bar and the descaling rate is 2 m / s.

[0025] Step 3, rough rolling: the descaled slab is subjected to intermediate rolling, with 5 passes of reduction, and the reduction rates are 41%, 32%, 32%, 22%, and 22% respectively, the rolling speed is 5 m / s, and the thickness of the rolled intermediate slab is 35 mm.

[0026] Step 4, finishing rolling: the intermediate billet thickened by rough rolling is subjected to finishing rolling, with 7 passes of reduction, and the reduction rates are 29%, 24%, 21%, 21%, 20%, 20%, 15% respectively, and the rolling speed is 9 m / s, and finally rolled into a finished product with a thickness of 6 mm.

[0027] Step 5: Curling: After rolling, the steel strip is rapidly curled at a speed of 5 m / s and a temperature of 650°C.

[0028] Step 6, annealing: after the coils are cooled to 350°C after leaving the production line, the hot coils are directly put into a bell-type furnace for annealing at 830°C. After annealing and holding for 15 hours, they are slowly cooled to 230°C and then taken out of the furnace. After being taken out of the furnace, the coils are cooled to room temperature and then packaged.

[0029] Example 3 A method for producing copper-containing antibacterial martensitic stainless steel black coils by a Steckel rolling mill comprises the following steps: Step 1, slab heating: send the 220mm thick slab cut by continuous casting into the preheating furnace for preheating, the furnace temperature is 600℃, the holding time is 200min, the preheated slab is sent into the heating furnace for heating and insulation, the insulation temperature is 1050℃, the heating rate is 3℃ / min, and the insulation time is 180min.

[0030] Step 2: Surface descaling: After leaving the furnace, the slab enters the descaling machine and is descaled using high-pressure water. The water pressure is 280 bar and the descaling rate is 2 m / s.

[0031] Step 3, rough rolling: the descaled slab is subjected to intermediate rolling, with 5 passes of reduction, and the reduction rates are 45%, 35%, 35%, 25%, and 25% respectively, the rolling speed is 5 m / s, and the thickness of the rolled intermediate slab is 40 mm.

[0032] Step 4, finishing rolling: the intermediate billet thickened by rough rolling is subjected to finishing rolling, with 7 passes of reduction, and the reduction rates are 40%, 30%, 30%, 30%, 30%, 30%, 20% respectively, and the rolling speed is 9 m / s, and finally rolled into a finished product with a thickness of 12 mm.

[0033] Step 5: Curling: After rolling, the steel strip is rapidly curled at a speed of 7 m / s and a temperature of 700°C.

[0034] Step 6, annealing: after the coils are cooled to 400℃ after leaving the production line, the hot coils are directly put into a bell-type furnace for annealing at 850℃. After annealing and holding for 15 hours, they are slowly cooled to 250℃ and then taken out of the furnace. After being taken out of the furnace, the coils are cooled to room temperature and then packaged.

[0035] After the production of copper-containing antibacterial martensitic stainless steel black coils by the Steckel rolling mill in Examples 1-3, the following Figure 1-2 The appearance of the edge of the copper-containing antibacterial martensitic stainless steel coil and the pickling surface appearance after rolling are shown. From the analysis of the appearance pictures, it can be seen that through the optimization control of the parameters of the rolling heating furnace heating temperature, the descaling water pressure and rate, the compression ratio of the rough rolling and finishing passes, and the control of the annealing temperature, the copper-containing antibacterial martensitic stainless steel with the coil edge cracks and surface peeling defects is finally rolled out, and the plate width and large coil thickness range of the copper-containing antibacterial martensitic stainless steel rolling production are improved, which greatly improves the overall production efficiency and quality of the copper-containing antibacterial martensitic stainless steel.

Claims

1. A method for producing copper-containing antibacterial martensitic stainless steel black coils by a Steckel mill, characterized in that: The following steps are involved: Step 1, slab heating: send the 220mm thick slab cut by continuous casting into the preheating furnace for preheating, the furnace temperature is 500℃-600℃, and the slab after preheating is sent into the heating furnace for heating and insulation, the heating temperature is 1000℃-1050℃, and the heating rate is 3℃ / min; Step 2, surface descaling: After the slab comes out of the heating furnace, it enters the descaling machine and is descaled with high-pressure water. The water pressure is ≥250bar and the descaling rate is 2m / s. Step 3, rough rolling: the descaled slab is subjected to intermediate rolling, with 5 passes of reduction, the reduction rates are 40%-45%, 30%-35%, 30%-35%, 20%-25% and 20%-25% respectively, and the rolling speed is 5m / s; Step 4, finishing rolling: the intermediate billet after rough rolling is finished rolling, and the rolling reduction rate is 20%-40%, 15%-30%, 15%-30%, 15%-30%, 15%-30%, 15%-30%, 15%-30% and 10%-20% respectively, and the rolling speed is 9m / s; Step 5, curling: After finishing rolling, the steel strip is quickly curled, the curling speed is 2m / s-7m / s, and the curling temperature is 600℃-700℃; Step 6, annealing: after the coil pile is cooled to 300℃-400℃ after coiling off the line, the hot coil is directly loaded into the hydrogen bell-type furnace for annealing at 820℃-850℃ and the annealing holding time is 10h-15h. Then it is slowly cooled to 200℃-250℃ and then taken out of the furnace. After the black coil is taken out of the furnace, it can be packaged after cooling to room temperature.

2. The method for producing copper-containing antibacterial martensitic stainless steel black coil by a Steckel mill according to claim 1, characterized in that: In step 1, the slab is kept warm in the preheating furnace for 150-200 minutes, and in the heating furnace for 150-180 minutes.

3. The method for producing copper-containing antibacterial martensitic stainless steel black coil by a Steckel mill according to claim 1, characterized in that: The thickness of the intermediate billet after rough rolling in step 3 is 25 mm-40 mm.

4. The method for producing copper-containing antibacterial martensitic stainless steel black coil by a Steckel mill according to claim 1, characterized in that: The black coil after being fired in step 6 has a width of 1000 mm to 1530 mm and a thickness of 3 mm to 12 mm.

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