阅读说明：本技术 一种含硼耐磨钢铸坯表面裂纹控制方法 (Method for controlling surface cracks of boron-containing wear-resistant steel casting blank ) 是由 李耀强 张卫攀 刘红艳 陈子刚 杜琦铭 徐桂喜 王青云 张建坤 于 2020-12-16 设计创作，主要内容包括：本发明涉及一种含硼耐磨钢铸坯表面裂纹控制方法,包括转炉冶炼、LF精炼、RH精炼和连铸工序；转炉冶炼工序中,控制钢水中N≤30ppm；LF精炼工序保证钢液中酸溶铝达到0.030-0.050wt%,之后顺序加入钛铁、硼铁,调整成分和温度；RH精炼工序的真空处理时间≥20min,纯脱气时间≥8min；连铸工序中,钢水过热度控制在5-30℃,二冷区水温控制在32-45℃,水比为0.5-0.7l/kg,保证铸坯出矫直区温度≥950℃；本发明可将含硼耐磨钢铸坯表面裂纹发生率控制在0.20%以内,提升含硼耐磨钢钢板的表面质量。(The invention relates to a method for controlling surface cracks of a boron-containing wear-resistant steel casting blank, which comprises the working procedures of converter smelting, LF refining, RH refining and continuous casting; in the smelting process of the converter, N in the molten steel is controlled to be less than or equal to 30 ppm; the LF refining process ensures that acid-soluble aluminum in the molten steel reaches 0.030-0.050wt%, and then ferrotitanium and ferroboron are sequentially added to adjust the components and the temperature; the vacuum treatment time of the RH refining process is more than or equal to 20min, and the pure degassing time is more than or equal to 8 min; in the continuous casting process, the superheat degree of molten steel is controlled to be 5-30 ℃, the water temperature of a secondary cooling area is controlled to be 32-45 ℃, the water ratio is 0.5-0.7l/kg, and the temperature of a casting blank discharged from a straightening area is guaranteed to be more than or equal to 950 ℃; the method can control the surface crack incidence rate of the boron-containing wear-resistant steel casting blank within 0.20 percent, and improve the surface quality of the boron-containing wear-resistant steel plate.)

1. A method for controlling surface cracks of a boron-containing wear-resistant steel casting blank comprises the working procedures of converter smelting, LF refining, RH refining and continuous casting; the method is characterized in that: in the converter smelting process, N in the molten steel is controlled to be less than or equal to 30 ppm;

the LF refining process ensures that acid-soluble aluminum in the molten steel reaches 0.030-0.050wt%, and then ferrotitanium and ferroboron are sequentially added to adjust components and temperature;

in the RH refining process, the vacuum treatment time is more than or equal to 20min, and the pure degassing time is more than or equal to 8 min;

in the continuous casting process, the superheat degree of molten steel is controlled to be 5-30 ℃, the water temperature of a secondary cooling area is controlled to be 32-45 ℃, the water ratio is 0.5-0.7l/kg, and the temperature of a casting blank discharged from a straightening area is guaranteed to be more than or equal to 950 ℃.

2. The method for controlling surface cracks of the boron-containing wear-resistant steel casting blank according to claim 1, wherein the method comprises the following steps: in the LF refining process, an aluminum wire is fed into a ladle to ensure that acid-soluble aluminum in molten steel reaches 0.030-0.050wt%, ferrotitanium is added and stirred uniformly, ferroboron is added, and the components and the temperature are adjusted;

in the RH refining process, under the condition that the vacuum degree is less than or equal to 50Pa, the vacuum treatment time is more than or equal to 20min, the pure degassing time is more than or equal to 8min, and the argon net blowing time of molten steel after RH refining is more than or equal to 6 min.

3. The method for controlling surface cracks of the boron-containing wear-resistant steel casting blank according to claim 1 or 2, wherein the method comprises the following steps: in the LF refining process, ferrotitanium is added and stirred uniformly, and ferroboron is added when TO is less than or equal TO 20ppm and N is less than or equal TO 50ppm in molten steel.

4. The boron-containing wear-resistant steel casting blank surface crack of claim 1The control method is characterized in that: in the continuous casting process, argon is blown to protect casting in the whole process, and the flow is controlled to be 5m³/h-25m³H, constant-speed casting at the speed of 0.75-1.30 m/min; controlling the superheat degree of molten steel at 5-30 ℃, controlling the water temperature of a secondary cooling area at 32-45 ℃, and controlling the water ratio at 0.5-0.7l/kg, so as to ensure that the temperature of a casting blank discharged from a straightening area is more than or equal to 950 ℃; the accuracy of the roll gap of the fan-shaped section is controlled to be-0.5 mm to +0.5mm, the arc alignment accuracy of each section is 0-0.5mm, and the hot blank pressure of the driving roll of the fan-shaped section is 6.6-7.6 MPa.

5. The method for controlling surface cracks of the boron-containing wear-resistant steel casting blank according to claim 1, wherein the method comprises the following steps: after RH vacuum treatment, N in the molten steel is less than or equal to 40 ppm.

Technical Field

The invention relates to the technical field of steel making, in particular to a method for controlling surface cracks of a boron-containing wear-resistant steel casting blank.

Background

The wear-resistant steel has good wear resistance and strength, and is widely applied to various industries of national economy. In a chemical component system of the wear-resistant steel, boron is an important element for improving hardenability, the storage capacity of China is large, the cost is lower compared with metal elements such as nickel and chromium, the economic effect is obvious, and the core hardness of the wear-resistant steel can be obviously improved only by adding a small amount (generally 5-35 ppm), so that the wear of the wear-resistant steel product is more uniform in use, and the service life is longer.

Research shows that boron has stronger crack sensitivity than metals such as niobium, aluminum and the like. In the smelting process, after boron is added, the boron is easy to react with carbon and nitrogen to generate carbide, nitride or carbonitride, the carbide, nitride or carbonitride is separated out at a crystal boundary to cause crystal boundary embrittlement, the thermoplasticity of a casting blank is reduced, transverse cracks on the surface are caused in continuous casting production, the transverse cracks are mostly distributed on the edge part and one side of an inner arc of the casting blank, the flame cleaning is needed to be carried out on the surface of the casting blank, but the deep cracks can only be judged or rejected. Sometimes, in consideration of edge cracks, an edge margin is reserved when a production plan is made, and the edge cracks are cut off when the production plan is finally sized, but the product yield is low, and the production cost is increased. Therefore, the control of the surface cracks of the boron-containing wear-resistant steel casting blank is a difficult problem to be solved urgently.

Disclosure of Invention

The invention aims to solve the technical problem of providing a method for controlling surface cracks of boron-containing wear-resistant steel casting blanks, which can control the surface crack incidence rate of the boron-containing wear-resistant steel casting blanks within 0.20 percent and improve the surface quality of boron-containing wear-resistant steel plates.

In order to solve the technical problems, the technical scheme adopted by the invention is as follows:

a method for controlling surface cracks of a boron-containing wear-resistant steel casting blank comprises the working procedures of converter smelting, LF refining, RH refining and continuous casting; in the converter smelting process, N in the molten steel is controlled to be less than or equal to 30 ppm;

the LF refining process ensures that acid-soluble aluminum in the molten steel reaches 0.030-0.050wt%, ferrotitanium and ferroboron are sequentially added, and the components and the temperature are adjusted;

in the RH refining process, the vacuum treatment time is more than or equal to 20min, and the pure degassing time is more than or equal to 8 min;

in the continuous casting process, the superheat degree of molten steel is controlled to be 5-30 ℃, the water temperature of a secondary cooling area is controlled to be 32-45 ℃, the water ratio is 0.5-0.7l/kg, and the temperature of a casting blank discharged from a straightening area is guaranteed to be more than or equal to 950 ℃.

In the LF refining process, an aluminum wire is fed into a steel ladle to ensure that acid-soluble aluminum in molten steel reaches 0.030-0.050wt%, ferrotitanium is added and stirred uniformly, ferroboron is added, and the components and the temperature are adjusted;

in the RH refining process, under the condition that the vacuum degree is less than or equal to 50Pa, the vacuum treatment time is more than or equal to 20min, the pure degassing time is more than or equal to 8min, and the argon net blowing time of molten steel after RH refining is more than or equal to 6 min.

According TO the method for controlling the surface cracks of the boron-containing wear-resistant steel casting blank, ferrotitanium is added in the LF refining process, and ferroboron is added when TO is less than or equal TO 20ppm and N is less than or equal TO 50ppm in molten steel after the ferrotitanium is added and stirred uniformly.

In the continuous casting process, argon is blown in the whole process to protect pouring, and the flow is controlled to be 5m³/h-25m³H, constant-speed casting at the speed of 0.75-1.30 m/min; controlling the superheat degree of molten steel at 5-30 ℃, controlling the water temperature of a secondary cooling area at 32-45 ℃, and controlling the water ratio at 0.5-0.7l/kg, so as to ensure that the temperature of a casting blank discharged from a straightening area is more than or equal to 950 ℃; the accuracy of the roll gap of the fan-shaped section is controlled to be-0.5 mm to +0.5mm, the arc alignment accuracy of each section is 0-0.5mm, and the hot blank pressure of the driving roll of the fan-shaped section is 6.6-7.6 MPa.

According to the method for controlling the surface cracks of the boron-containing wear-resistant steel casting blank, N in the molten steel is less than or equal to 40ppm after RH vacuum treatment.

According to the method for controlling the surface cracks of the boron-containing wear-resistant steel casting blank, the converter smelting process adopts a bottom argon blowing process in the whole process, the dephosphorization operation is carried out, and the over-blowing is avoided.

The boron-containing wear-resistant steel comprises the following chemical components in percentage by mass: c: 0.15% -0.25%, Si: 0.10-0.30%, Mn: 1.10% -1.40%, Nb: 0.015-0.035%, Ti: 0.010-0.030%, Cr: 0.40% -0.60%, Mo: 0.15% -0.45%, B: 0.0005 to 0.0035 percent of Fe and residual elements and impurities which are inevitable in the production process.

In the smelting process of the converter, on the basis of decarburization and dephosphorization, the contact between molten steel and air is reduced as much as possible, the nitrogen content in the molten steel is reduced, and conditions are created for subsequent production; the bottom-blown argon gas adopted can better and uniformly contact and react oxygen and carbon in molten steel to generate carbon monoxide and carbon dioxide, and the carbon monoxide and the carbon dioxide float upwards in a bubble mode, and nitrogen dissolved in the molten steel forms nitrogen in full collision and also floats upwards and is discharged.

In LF refining production, firstly aluminum is used for deep deoxidation, then ferrotitanium is added for nitrogen fixation, and ferroboron is added when TO is less than or equal TO 20ppm and N is less than or equal TO 50ppm in molten steel, because boron has strong affinity with oxygen and nitrogen, but the affinity of aluminum with oxygen is stronger than that of boron and titanium, and the affinity of titanium with nitrogen is stronger than that of boron, the deep deoxidation is carried out by aluminum, and then titanium is used for deep denitrification.

And in the RH vacuum treatment, nitrogen in the molten steel is continuously removed, the generation of boron nitride is reduced, and after the treatment is finished, the N in the molten steel is less than or equal to 45 ppm.

In the slab continuous casting production, protective casting is adopted, argon blowing operation is carried out at a water gap, molten steel is prevented from contacting with air, and increase of nitrogen in the molten steel is reduced, so that the content of boron nitride in the molten steel is reduced. And controlling the water temperature and water quantity of the secondary cooling area, ensuring that the temperature of the casting blank out of the straightening area is more than or equal to 950 ℃, controlling the accuracy of the sector section and the hot blank pressure of the driving roller, and reducing the mechanical stress while ensuring the blank drawing speed.

The solubility of boron in steel is low, boron is easy to be segregated on grain boundaries, when molten steel contains nitrogen, a large amount of fine boron nitride can be separated out on austenite grain boundaries, and the substances can be firmly 'pinned' on the grain boundaries to prevent the grain boundaries from sliding, so that the grains are broken, and macroscopically, the thermoplasticity of the steel is greatly reduced.

According to the high-temperature plasticity characteristics of the boron-containing wear-resistant steel, a casting blank has two obvious high-temperature low-plasticity areas which are 850-950 ℃ and 1250 ℃ respectively, and if the temperature of the casting blank in a straightening area is in a high-temperature low-plasticity area and is overlapped with the temperature at which a large amount of nitride is separated out, the brittleness of the steel is increased, and cracks appear at the trough of vibration marks of the casting blank.

Therefore, in order to avoid surface cracks of boron-containing steel and increase the thermoplasticity of the steel, on one hand, the nitrogen content of molten steel is controlled in the whole process, the generation of nitride is reduced, and on the other hand, the temperature avoids a high-temperature low-plasticity zone when the casting blank is taken out of a bending and straightening section.

According to the method, the nitrogen content in the molten steel is accurately controlled through the whole process, the content of nitride is reduced, and the plasticity of the steel is reduced as much as possible due to precipitation of boron nitride at crystal boundaries; the method comprises the steps of firstly controlling the nitrogen content of the converter, keeping the nitrogen content at a lower level, carrying out deep deoxidation and deep denitrification treatment on the molten steel in an LF refining process by designing the adding sequence and adding amount of Al, Ti and B, and continuously reducing the nitrogen content in the molten steel as much as possible and reducing the generation of boron nitride in a subsequent RH and continuous casting process, thereby reducing the pinning effect on a crystal boundary; the water quantity and the water temperature of a secondary cooling area of continuous casting are controlled, weak cooling is carried out on a hot blank, the temperature of the casting blank in a bending and straightening section is guaranteed to be larger than or equal to 950 ℃, a high-temperature low-plasticity area of steel is avoided, the mechanical action of a fan-shaped section on the hot blank is controlled, the problem of surface cracks of the boron-containing wear-resistant steel casting blank is finally solved, the yield of a steel plate is improved, and the surface quality of a product is guaranteed.

The invention has the beneficial effects that:

the method can obviously reduce the surface crack incidence rate of the boron-containing wear-resistant steel casting blank from 1.80 percent to within 0.20 percent, improve the surface quality of the wear-resistant steel plate, further effectively improve the yield of the steel plate, and improve the yield from 87.3 percent to over 90.2 percent.

Detailed Description

The invention relates to a method for controlling surface cracks of a boron-containing wear-resistant steel casting blank, which comprises the following steps of converter smelting, LF refining, RH refining and slab continuous casting:

(1) smelting in a converter: the whole process adopts a bottom argon blowing process to carry out dephosphorization operation, over-blowing is avoided, and N is less than or equal to 30 ppm;

(2) LF refining: feeding an aluminum wire of 150-250 m into a steel ladle TO ensure that acid-soluble aluminum in the molten steel reaches 0.030-0.050wt%, firstly adding ferrotitanium, after the molten steel is uniformly stirred, adding ferroboron when TO in the molten steel is less than or equal TO 20ppm and N in the molten steel is less than or equal TO 50ppm, wherein the argon net blowing time of the steel ladle is more than or equal TO 3min, and ensuring that the components and the temperature of the molten steel are uniform;

(3) RH vacuum treatment: under the condition that the vacuum degree is less than or equal to 50Pa, the vacuum treatment time is more than or equal to 20min, the pure degassing time is more than or equal to 8min, and the argon net blowing time of molten steel after RH refining is more than or equal to 6 min;

(4) slab continuous casting: argon blowing protection pouring is carried out in the whole process, and the flow is controlled to be 5m³/h-25m³H, casting at a constant speed of 0.75-1.30 m/min; the superheat degree of molten steel is controlled to be 5-30 ℃, the water temperature of a secondary cooling area is controlled to be 32-45 ℃, the water ratio is 0.5-0.7l/kg, the temperature of a casting blank out of a straightening area is guaranteed to be more than or equal to 950 ℃, the roll gap precision of a fan-shaped section is controlled to be-0.5 mm to +0.5mm, the arc-aligning precision of each section is 0-0.5mm, and the hot blank pressure of a driving roll of the fan-shaped section is 6.6-7.6 MPa.

Through the control, the surface quality of the boron-containing wear-resistant steel is obviously improved; the surface crack defect of the billet is effectively controlled.

The invention is further illustrated by the following specific examples in which all component percentages are by weight.

In examples 1 to 6, 100 ton converter, 100 ton LF furnace, 100 ton RH furnace and 180-260mm section large slab caster were used to produce boron-containing wear resistant steel, and the chemical compositions of each example are shown in Table 1.

Table 1 examples 1-6 boron-containing wear resistant steel chemistries (wt%)

[ example 1 ]

The embodiment is a method for controlling surface cracks of a boron-containing wear-resistant steel casting blank, which comprises the following steps:

(1) smelting in a converter: the whole process adopts a bottom argon blowing process to carry out dephosphorization operation, over-blowing is avoided, and N is 28 ppm;

(2) LF refining: feeding an aluminum wire 150 m into a steel ladle TO ensure that acid-soluble aluminum in molten steel reaches 0.030wt%, firstly adding ferrotitanium, after the molten steel is uniformly stirred, adding ferroboron when TO in the molten steel is 20ppm and N in the molten steel is 45ppm, and blowing the steel ladle for 5min TO ensure that the components and the temperature of the molten steel are uniform;

(3) RH vacuum treatment: under the condition of a vacuum degree of 50Pa, the vacuum treatment time is 35min, the pure degassing time is 8min, the argon net blowing time of molten steel after RH refining is 8min, and the N content of the molten steel is 40 ppm;

(4) slab continuous casting: argon blowing protection pouring is carried out in the whole process, and the flow is controlled to be 10m³H, constant-speed casting at the speed of 0.91 m/min; the superheat degree of the molten steel is controlled to be 5 ℃, the water temperature of a secondary cooling area is controlled to be 35 ℃, the water ratio is 0.65l/kg, and the temperature of a casting blank discharged from a straightening area is guaranteed to be more than or equal to 950 ℃; the accuracy of the roll gap of the sector section is controlled to be-0.5 mm, the arc alignment accuracy of each section is 0mm, and the hot blank pressure of the drive roll of the sector section is 7.6 MPa;

through the control, the surface quality of the boron-containing wear-resistant steel is obviously improved; no cracks are generated on the surfaces of the casting blank and the rolled steel plate.

[ example 2 ]

The embodiment is a method for controlling surface cracks of a boron-containing wear-resistant steel casting blank, which comprises the following steps:

(1) smelting in a converter: the whole process adopts a bottom argon blowing process to carry out dephosphorization operation, over-blowing is avoided, and N is 25 ppm;

(2) LF refining: feeding 223 m of aluminum wires into a steel ladle TO ensure that acid-soluble aluminum in molten steel reaches 0.047%, adding ferrotitanium, after the molten steel is uniformly stirred, adding ferroboron when TO in the molten steel is 18ppm and N in the molten steel is 47ppm, and blowing the steel ladle for 4min TO ensure that the components and the temperature of the molten steel are uniform;

(3) RH vacuum treatment: under the condition of a vacuum degree of 12Pa, the vacuum treatment time is 31min, the pure degassing time is 10min, the argon net blowing time of molten steel after RH refining is 6min, and the N content of the molten steel is 42 ppm;

(4) slab continuous casting: argon blowing protection pouring is carried out in the whole process, and the flow is controlled to be 20m³H, constant-speed casting at the speed of 0.75 m/min; the superheat degree of the molten steel is controlled at 30 ℃, the water temperature of the secondary cooling area is controlled at 32 ℃, the water ratio is 0.55l/kg, and the temperature of the casting blank discharged from the straightening area is guaranteed to be more than or equal to 950 ℃. The accuracy of the roll gap of the sector section is controlled to be-0.2 mm, the arc alignment accuracy of each section is 0.1mm, and the hot blank pressure of the drive roll of the sector section is 7.5 MPa;

through the control, the surface quality of the boron-containing wear-resistant steel is obviously improved. No cracks are generated on the surfaces of the casting blank and the rolled steel plate.

[ example 3 ]

The embodiment is a method for controlling surface cracks of a boron-containing wear-resistant steel casting blank, which comprises the following steps:

(1) smelting in a converter: the whole process adopts a bottom argon blowing process to carry out dephosphorization operation, over-blowing is avoided, and N is 30 ppm;

(2) LF refining: feeding an aluminum wire into a steel ladle for 250 meters TO ensure that acid-soluble aluminum in the molten steel reaches 0.050 percent, firstly adding ferrotitanium, after the molten steel is uniformly stirred, adding ferroboron when TO in the molten steel is 15ppm and N in the molten steel is 50ppm, and blowing the steel ladle for 3min TO ensure that the components and the temperature of the molten steel are uniform;

(3) RH vacuum treatment: under the condition of a vacuum degree of 27Pa, the vacuum treatment time is 20min, the pure degassing time is 9min, the argon net blowing time of molten steel after RH refining is 10min, and the N content of the molten steel is 45 ppm;

(4) slab continuous casting: all-purposeArgon blowing protection pouring is carried out, and the flow is controlled to be 5m³H, keeping constant-speed casting at 1.02 m/min; the superheat degree of molten steel is controlled at 21 ℃, the water temperature of a secondary cooling area is controlled at 40 ℃, the water ratio is 0.50l/kg, the temperature of a casting blank out of a straightening area is guaranteed to be more than or equal to 950 ℃, the roll gap precision of a sector section is controlled at 0.5mm, the arc-alignment precision of each section is 0.4mm, and the hot blank pressure of a driving roll of the sector section is 7.1 MPa.

Through the control, the surface quality of the boron-containing wear-resistant steel is obviously improved. No cracks are generated on the surfaces of the casting blank and the rolled steel plate.

[ example 4 ]

The embodiment is a method for controlling surface cracks of a boron-containing wear-resistant steel casting blank, which comprises the following steps:

(1) smelting in a converter: the whole process adopts a bottom argon blowing process to carry out dephosphorization operation, over-blowing is avoided, and N is 29 ppm;

(2) LF refining: feeding an aluminum wire for 200 meters into a steel ladle, ensuring that acid-soluble aluminum in molten steel reaches 0.045%, firstly adding ferrotitanium, uniformly stirring the molten steel, then adding ferroboron when TO in the molten steel is 19ppm and N in the molten steel is 42ppm, and blowing the steel ladle for 5min TO ensure that the components and the temperature of the molten steel are uniform;

(3) RH vacuum treatment: under the condition of a vacuum degree of 41Pa, the vacuum treatment time is 30min, the pure degassing time is 12min, the argon net blowing time of molten steel after RH refining is 7min, and the N content of the molten steel is 37 ppm;

(4) slab continuous casting: argon blowing protection pouring is carried out in the whole process, and the flow is controlled to be 12m³H, keeping constant-speed casting at 1.00 m/min, controlling the superheat degree of molten steel at 8 ℃, controlling the water temperature of a secondary cooling area at 45 ℃ and the water ratio at 0.70l/kg, and ensuring that the temperature of a casting blank discharged from a straightening area is more than or equal to 950 ℃; the accuracy of the roll gap of the sector section is controlled to be 0.3mm, the arc alignment accuracy of each section is 0.5mm, and the hot blank pressure of the drive roll of the sector section is 6.6 MPa.

Through the control, the surface quality of the boron-containing wear-resistant steel is obviously improved. No cracks are generated on the surfaces of the casting blank and the rolled steel plate.

[ example 5 ]

The embodiment is a method for controlling surface cracks of a boron-containing wear-resistant steel casting blank, which comprises the following steps:

(1) smelting in a converter: the whole process adopts a bottom argon blowing process to carry out dephosphorization operation, over-blowing is avoided, and N is 26 ppm;

(2) LF refining: feeding an aluminum wire for 199 m into a steel ladle TO ensure that acid-soluble aluminum in molten steel reaches 0.040%, firstly adding ferrotitanium, uniformly stirring the molten steel, then adding ferroboron when TO in the molten steel is 12ppm and N in the molten steel is 40ppm, and blowing the steel ladle for 4min TO ensure that the components and the temperature of the molten steel are uniform;

(3) RH vacuum treatment: under the condition of a vacuum degree of 36Pa, the vacuum treatment time is 22min, the pure degassing time is 11min, the argon net blowing time of molten steel after RH refining is 9min, and the N content of the molten steel is 35 ppm;

(4) slab continuous casting: argon blowing protection pouring is carried out in the whole process, and the flow is controlled to be 25m³And h, constant-speed casting at the speed of 1.30m/min is kept, the superheat degree of molten steel is controlled at 27 ℃, the water temperature of a secondary cooling area is controlled at 33 ℃, the water ratio is 0.57l/kg, the temperature of a casting blank out of a straightening area is guaranteed to be more than or equal to 950 ℃, the roll gap precision of a sector section is controlled at 0mm, the arc-aligning precision of each section is 0.2mm, and the hot blank pressure of a driving roll of the sector section is 7.6 MPa.

Through the control, the surface quality of the boron-containing wear-resistant steel is obviously improved. No cracks are generated on the surfaces of the casting blank and the rolled steel plate.

[ example 6 ]

The embodiment is a method for controlling surface cracks of a boron-containing wear-resistant steel casting blank, which comprises the following steps:

(1) smelting in a converter: the whole process adopts a bottom argon blowing process to carry out dephosphorization operation, over-blowing is avoided, and N is 24 ppm;

(2) LF refining: feeding an aluminum wire of 176 meters into a steel ladle TO ensure that acid-soluble aluminum in molten steel reaches 0.031 percent, adding ferrotitanium, after the molten steel is uniformly stirred, adding ferroboron when TO in the molten steel is 17ppm and N in the molten steel is 41ppm, and blowing the steel ladle for 6min TO ensure that the components and the temperature of the molten steel are uniform;

(3) RH vacuum treatment: under the condition of the vacuum degree of 0Pa, the vacuum treatment time is 25min, the pure degassing time is 13min, the argon net blowing time of molten steel after RH refining is 11min, and the N content of the molten steel is 36 ppm.

(4) Slab continuous casting: argon blowing protection pouring is carried out in the whole process, and the flow is controlled to be 21m³H, constant-speed casting at 0.88 m/min, controlling the superheat degree of molten steel at 8 ℃, the water temperature of a secondary cooling zone at 42 ℃ and the water ratio at 062l/kg, and ensuring that the temperature of the casting blank out of a straightening area is more than or equal to 950 ℃; the accuracy of the roll gap of the sector section is controlled to be 0.1mm, the arc alignment accuracy of each section is 0.3mm, and the hot blank pressure of the drive roll of the sector section is 6.8 MPa.

Through the control, the surface quality of the boron-containing wear-resistant steel is obviously improved. No cracks are generated on the surfaces of the casting blank and the rolled steel plate.