CN110904395A - Sulfur-containing free-cutting steel and smelting method thereof - Google Patents
Sulfur-containing free-cutting steel and smelting method thereof Download PDFInfo
- Publication number
- CN110904395A CN110904395A CN201911303966.1A CN201911303966A CN110904395A CN 110904395 A CN110904395 A CN 110904395A CN 201911303966 A CN201911303966 A CN 201911303966A CN 110904395 A CN110904395 A CN 110904395A
- Authority
- CN
- China
- Prior art keywords
- molten steel
- blowing
- steel
- ladle
- content
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/60—Ferrous alloys, e.g. steel alloys containing lead, selenium, tellurium, or antimony, or more than 0.04% by weight of sulfur
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/28—Manufacture of steel in the converter
- C21C5/30—Regulating or controlling the blowing
- C21C5/35—Blowing from above and through the bath
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/04—Making ferrous alloys by melting
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/42—Ferrous alloys, e.g. steel alloys containing chromium with nickel with copper
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Mechanical Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Treatment Of Steel In Its Molten State (AREA)
- Carbon Steel Or Casting Steel Manufacturing (AREA)
Abstract
The invention discloses a sulfur-containing free-cutting steel and a smelting method thereof, wherein the smelting method of the sulfur-containing free-cutting steel comprises the following steps: 1) blowing the molten iron through a top-bottom combined blowing converter, and tapping; 2) hoisting the molten steel blown in the step 1) to a refining process, and refining in an LF refining furnace; 3) hoisting the molten steel refined by LF in the step 2) to a continuous casting process for full-process protective casting; in the step 1), a converter blowing process adopts a high-tension complementary blowing mode for blowing, the content of the blown molten steel C is not more than 0.04 wt%, the content of P is not more than 0.045 wt%, and the tapping temperature is 1630-1660 ℃. The sulfur-containing free-cutting steel has excellent cutting performance, and the smelting method has the advantages of simple process and convenient operation.
Description
Technical Field
The invention relates to steel, in particular to sulfur-containing free-cutting steel and a smelting method thereof.
Background
With the development of high speed, precision and automation of machining, especially in the automobile industry, the precision instrument industry and household appliances, it is generally desired to reduce the machining cost by improving the machining performance of steel materials in consideration of the fact that the machining cost is an important component of the manufacturing cost of parts in the manufacturing industry (sometimes even reaching 40% -60% of the manufacturing cost of parts). Various factors promote the increase of the yield and variety of the free-cutting steel and the continuous improvement of the quality. Free-cutting steel is a steel grade aimed at reducing machining cost (lowering tool cost and improving work efficiency), improving cutting quality, reducing cutting resistance, or improving cutting processability in automatic machine tools for machining, and is an energy-saving material that is increasingly widely used in the development of the mechanical industry.
In the production of free-cutting steel, free-cutting elements S, P, Pb, Se, Te, Bi, Sn, etc., which are harmful elements or residual elements for most steel grades (especially clean steel or ultra-pure steel), are added, in the sense that the composition and process design of free-cutting steel are almost opposite to those of all other steel grades, which brings great difficulty to the development and production of free-cutting steel.
Disclosure of Invention
The invention aims to provide sulfur-containing free-cutting steel and a smelting method thereof, wherein the sulfur-containing free-cutting steel has excellent cutting performance, and the smelting method has the advantages of simple process and convenient operation.
In order to achieve the above object, the present invention provides a method for melting sulfur-containing free-cutting steel, comprising:
1) blowing the molten iron through a top-bottom combined blowing converter, and tapping;
2) hoisting the molten steel blown in the step 1) to a refining process, and refining in an LF refining furnace;
3) hoisting the molten steel refined by LF in the step 2) to a continuous casting process for full-process protective casting;
in the step 1), a converter blowing process adopts a high-tension complementary blowing mode for blowing, the content of the blown molten steel C is not more than 0.04 wt%, the content of P is not more than 0.045 wt%, and the tapping temperature is 1630-1660 ℃.
The invention also provides the sulfur-containing free-cutting steel which is obtained by smelting through the smelting method.
Through the technical scheme, the invention strictly controls the content of each element through the whole-process protective casting of the blowing, refining and continuous casting processes of the top-bottom combined blown converter of the molten iron, ensures that the prepared steel not only can ensure excellent free-cutting property, but also can solve the unstable casting problems of out-of-control refractory material erosion casting flow, unstable drawing speed, drawing leakage and the like, thereby overcoming a series of technical problems of high sulfur, high oxygen, continuous casting leakage, difficult control of the surface quality of a casting blank and the like, and successfully developing the free-cutting steel.
Additional features and advantages of the invention will be set forth in the detailed description which follows.
Detailed Description
The following describes in detail specific embodiments of the present invention. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.
The invention provides a smelting method of sulfur-containing free-cutting steel, which comprises the following steps:
1) blowing the molten iron through a top-bottom combined blowing converter, and tapping;
2) hoisting the molten steel blown in the step 1) to a refining process, and refining in an LF refining furnace;
3) hoisting the molten steel refined by LF in the step 2) to a continuous casting process for full-process protective casting;
in the step 1), a converter blowing process adopts a high-tension complementary blowing mode for blowing, the content of the blown molten steel C is not more than 0.04 wt%, the content of P is not more than 0.045 wt%, and the tapping temperature is 1630-1660 ℃.
In the present invention, in order to further improve the free-cutting property and other properties of the steel product, it is preferable that in step 1), aluminum iron, sulfur iron, alloys (silicomanganese and low-carbon ferromanganese), and slag are added to the ladle in order at the time of tapping 1/4; wherein the addition amount of the aluminum iron is 2.3-2.5kg/t, the addition amount of the sulfur iron is 8.0-8.5kg/t, the addition amount of the silicon-manganese alloy is 2.3-2.5kg/t, and the balance is supplemented with low-carbon ferromanganese to ensure that the content of Mn is 1.10-1.20 wt% when the LF enters the station; the slag charge is 3.0-3.3kg/t lime.
In the present invention, in order to further improve the free-cutting property and other properties of the produced steel, it is preferable that in step 1), argon is bottom-blown throughout the ladle, subject to the fact that molten steel does not splash into the ladle; after steel tapping is finished, the flow of bottom blowing argon is adjusted to the position of 500mm of the bright surface of 300-.
In the present invention, in order to further improve the free-cutting property and other properties of the steel product obtained, it is preferable that in step 1), the tapping be strictly prohibited from slag removal and, if necessary, the steel leaving operation be performed.
In step 2) of the present invention, the contents of the respective elements may vary within wide ranges, but in order to further improve the free-cutting property and other properties of the produced steel, it is preferable that in step 2), the molten steel is melted with the following composition: 0.05 to 0.09 weight percent of C, 0.01 to 0.03 weight percent of Si, 0.045 to 0.055 weight percent of P, 1.25 to 1.35 weight percent of Mn, 0.35 to 0.40 weight percent of S, and the weight ratio of Mn to S is 3 to 5: 1.
in step 2) of the invention, in order to further improve the free-cutting property and other properties of the prepared steel, preferably, in step 2), 1.5-2.5kg/t of lime and 0.38-0.40kg/t of calcium carbide are added after molten steel enters a station, ferrosilicon powder can be floated on the slag surface in the electrifying process to control the oxygen balance of slag, and the binary alkalinity of refining slag is 2.5-3.0; after the slag is refined, the component adjustment operation is carried out, the hit rate of the adjusted component is improved, and the times of adjusting the component are reduced.
In step 2) of the present invention, in order to further improve the free-cutting property and other properties of the steel product, it is preferable that in step 2), oxygen is controlled throughout the refining process, and oxygen is determined using a heili oxygen determinator; when the oxygen content of the molten steel is higher than 60PPm, adding aluminum iron or feeding silicon barium lines to reduce the oxygen content of the molten steel; when the oxygen content of the molten steel is lower than 40PPm, adjusting the bottom blowing flow of the steel ladle, adding iron scale and increasing the oxygen content of the molten steel; when the oxygen content of the molten steel is 40-55PPm, the molten steel is not processed, and the oxygen content of the molten steel outbound target is about 50 PPm.
In step 2) of the present invention, in order to further improve the free-cutting property and other properties of the produced steel, it is preferable that in step 2), the calcium treatment is prohibited, and the soft blow time: the soft blowing time of the first furnace for casting is not less than 15min (preferably 15-20min), and the soft blowing time of the following continuous casting furnace (the furnace time of the first furnace for casting) is not less than 10min (preferably 10-15 min).
In step 3) of the invention, in order to further improve the machinability and other properties of the prepared steel, preferably, in step 3), the continuous casting protection pouring adopts a large-ladle sleeve argon blowing protection and integral nozzle casting mode, the degree of superheat of a ladle in a first furnace is 35-45 ℃, the degree of superheat of a ladle in a continuous casting furnace is 30-40 ℃, and the degree of superheat is controlled by adopting a crystallizer electromagnetic stirring mode and a tail end electric mode.
The invention also provides the sulfur-containing free-cutting steel which is obtained by smelting through the smelting method.
The present invention will be described in detail below by way of examples.
Example 1
1) And blowing the molten iron into a top-bottom combined blown converter by a high-tension complementary blowing mode, wherein the content of C in the blown molten steel is 0.02 weight percent, and the content of P in the blown molten steel is 0.042 weight percent. Tapping, wherein the tapping temperature is 1650 ℃, and aluminum iron, sulfur iron, alloy and slag charge are sequentially added into a ladle when tapping 1/4; wherein the addition amount of the aluminum iron is 2.4kg/t, the addition amount of the sulfur iron is 8.2kg/t, the addition amount of the silicon manganese is 2.4kg/t, and the balance is supplemented with low-carbon ferromanganese to ensure that the content of Mn is 1.15 wt% when the LF enters the station; the slag charge is 3.2kg/t lime. Bottom blowing argon in the whole process of the ladle, wherein the ladle is tapped on the basis that molten steel does not splash; after tapping, adjusting the flow of bottom blowing argon to the position of 400mm of a bright surface; the slag is strictly forbidden in the tapping process, and steel is remained when necessary
2) And (2) blowing the molten steel obtained in the step 1) (the molten steel satisfies the following conditions: the content of C is 0.07 wt%, the content of Si is 0.02 wt%, the content of P is 0.050 wt%, the content of Mn is 1.30 wt%, and the content of S is 0.38 wt%, the refining process is carried out in an LF refining furnace (2.0 kg/t lime and 0.39kg/t calcium carbide are added after the refining furnace enters the refining furnace, ferrosilicon powder can be floated on the slag surface in the electrifying process to control the oxygen balance of slag, the binary alkalinity of refining slag is 2.8), and after the refining slag is refined, component adjustment operation is carried out, the component hit rate is improved and adjusted, and the component adjustment times are reduced. Controlling oxygen in the whole refining process, and determining oxygen by using a Helli oxygen determination instrument; when the oxygen content of the molten steel is higher than 60PPm, adding aluminum iron or feeding silicon barium lines to reduce the oxygen content of the molten steel; when the oxygen content of the molten steel is lower than 40PPm, adjusting the bottom blowing flow of the steel ladle, adding iron scale and increasing the oxygen content of the molten steel; when the oxygen content of the molten steel is 40-55PPm, the molten steel is not treated, and when the molten steel is discharged, the oxygen content is 50 PPm. Calcium treatment is forbidden in the refining process, and the soft blowing time is as follows: the soft blowing time of the first furnace for casting is 20min, and the soft blowing time of the following continuous casting furnace is 15 min.
3) And (3) hoisting the molten steel refined by LF in the step 2) to a continuous casting process for full-process protective casting. The continuous casting protection pouring adopts a large ladle sleeve argon blowing protection and integral nozzle pouring mode, the superheat degree of a ladle in a first furnace is 40 ℃, the superheat degree of a ladle in a continuous casting furnace is 35 ℃, and the superheat degree is controlled by adopting a crystallizer electromagnetic stirring and end electric mode.
Example 2
1) And blowing the molten iron into a top-bottom combined blown converter by a high-tension complementary blowing mode, wherein the content of molten steel C after blowing is 0.03 weight percent, and the content of P is 0.040 weight percent. Tapping, wherein the tapping temperature is 1630 ℃, and aluminum iron, sulfur iron, alloy and slag charge are added into the ladle in sequence when tapping 1/4; wherein the addition amount of the aluminum iron is 2.3kg/t, the addition amount of the sulfur iron is 8.0kg/t, the addition amount of the silicon manganese is 2.3kg/t, and the balance is supplemented with low-carbon ferromanganese to ensure that the content of Mn is 1.10 wt% when the LF enters the station; the slag charge is 3.0kg/t lime. Bottom blowing argon in the whole process of the ladle, wherein the ladle is tapped on the basis that molten steel does not splash; after tapping, adjusting the flow of bottom blowing argon to the position of 300mm of a bright surface; the slag is strictly forbidden in the tapping process, and steel is remained when necessary
2) And (2) blowing the molten steel obtained in the step 1) (the molten steel satisfies the following conditions: the content of C is 0.05 wt%, the content of Si is 0.01 wt%, the content of P is 0.045 wt%, the content of Mn is 1.25 wt%, and the content of S is 0.40 wt%, the refining process is carried out in an LF refining furnace (1.5 kg/t lime and 0.38kg/t calcium carbide are added after the refining furnace enters the refining furnace, ferrosilicon powder can be floated on the slag surface in the electrifying process to control the oxygen balance of slag, the binary alkalinity of refining slag is 3.0), and after the refining slag is refined, the component adjustment operation is carried out, so that the component hit rate is improved and the component adjustment times are reduced. Controlling oxygen in the whole refining process, and determining oxygen by using a Helli oxygen determination instrument; when the oxygen content of the molten steel is higher than 60PPm, adding aluminum iron or feeding silicon barium lines to reduce the oxygen content of the molten steel; when the oxygen content of the molten steel is lower than 40PPm, adjusting the bottom blowing flow of the steel ladle, adding iron scale and increasing the oxygen content of the molten steel; when the oxygen content of the molten steel is 40-55PPm, the molten steel is not treated, and the oxygen content of the molten steel at the outlet is about 48 PPm. Calcium treatment is forbidden in the refining process, and the soft blowing time is as follows: the soft blowing time of the first furnace for casting is 15min, and the soft blowing time of the following continuous casting furnace is 10 min.
3) And (3) hoisting the molten steel refined by LF in the step 2) to a continuous casting process for full-process protective casting. The continuous casting protection pouring adopts a large ladle sleeve argon blowing protection and integral nozzle pouring mode, the superheat degree of a ladle in a first furnace is 35 ℃, the superheat degree of a ladle in a continuous casting furnace is 30 ℃, and the superheat degree is controlled by adopting a crystallizer electromagnetic stirring and end electric mode.
Example 3
Example 1
1) And blowing the molten iron into a top-bottom combined blown converter by a high-tension complementary blowing mode, wherein the content of C in the blown molten steel is 0.03 weight percent, and the content of P in the blown molten steel is 0.042 weight percent. Tapping, wherein the tapping temperature is 1660 ℃, and aluminum iron, sulfur iron, alloy and slag are added into a ladle in sequence when tapping 1/4; wherein the addition amount of the aluminum iron is 2.5kg/t, the addition amount of the sulfur iron is 8.5kg/t, the addition amount of the silicon manganese is 2.5kg/t, and the balance is supplemented with low-carbon ferromanganese to ensure that the content of Mn is 1.20 wt% when the LF enters the station; the slag charge is 3.3kg/t lime. Bottom blowing argon in the whole process of the ladle, wherein the ladle is tapped on the basis that molten steel does not splash; after tapping, adjusting the flow of bottom blowing argon to 500mm of bright surface; the slag is strictly forbidden in the tapping process, and steel is remained when necessary
2) And (2) blowing the molten steel obtained in the step 1) (the molten steel satisfies the following conditions: the content of C is 0.09 wt%, the content of Si is 0.03 wt%, the content of P is 0.055 wt%, the content of Mn is 1.35 wt%, and the content of S is 0.35 wt%, the refining process is carried out in an LF refining furnace (2.5 kg/t lime and 0.40kg/t calcium carbide are added after the refining process is finished, ferrosilicon powder can be floated on the slag surface in the electrifying process to control the oxygen balance of slag, the binary alkalinity of refining slag is 3.0), and after the refining is finished, the component adjustment operation is carried out, so that the component hit rate is improved, and the component adjustment times are reduced. Controlling oxygen in the whole refining process, and determining oxygen by using a Helli oxygen determination instrument; when the oxygen content of the molten steel is higher than 60PPm, adding aluminum iron or feeding silicon barium lines to reduce the oxygen content of the molten steel; when the oxygen content of the molten steel is lower than 40PPm, adjusting the bottom blowing flow of the steel ladle, adding iron scale and increasing the oxygen content of the molten steel; when the oxygen content of the molten steel is 40-55PPm, the molten steel is not processed, and the oxygen content of the molten steel at the outlet is about 52 PPm. Calcium treatment is forbidden in the refining process, and the soft blowing time is as follows: the soft blowing time of the first furnace for casting is 25min, and the soft blowing time of the next continuous casting furnace is 15 min.
3) And (3) hoisting the molten steel refined by LF in the step 2) to a continuous casting process for full-process protective casting. The continuous casting protection pouring adopts a large ladle sleeve argon blowing protection and integral nozzle pouring mode, the superheat degree of a ladle in a first furnace is 45 ℃, the superheat degree of a ladle in a continuous casting furnace is 40 ℃, and the superheat degree is controlled by adopting a crystallizer electromagnetic stirring and end electric mode.
Detection example 1
1) The free-cutting steel obtained by the smelting is tested according to the standard of Q HGJ 2139-2012, and the test chemical components are shown in the following table 1.
TABLE 1
By comparison, the free-cutting steel prepared by the method completely meets the standard of Q HGJ 2139-.
TABLE 2
| (％) | C | Si | Mn | P | S |
| 1215MS | ≤0.09 | ≤0.10 | 1.00-1.50 | 0.04-0.08 | 0.25-0.40 |
The allowable deviation of the chemical components of the finished product of the steel is +/-0.03% when S is less than or equal to 0.33% (smelting analysis); s is more than 0.33 percent (melting analysis), the allowable deviation is +/-0.04 percent, and the allowable deviation of the chemical components of the finished products of the other elements is in accordance with the GB/T222 specification.
2) The free-cutting steel is made into rolled steel wire rods, and then the rolled steel wire rods are tested according to the standard of Q _ XG178-2015, and the test items, the number of samples, the sampling method, the sampling position and the test method of each batch of the wire rods are implemented according to the specification of Table 3.
TABLE 3
| Inspection item | Number of samples | Sampling method and site | Test method | |
| 1 | Chemical composition (melting composition) | 1/furnace | GB/T 20066 | GB/T 4336 |
| 2 | Stretching | 2/batch | GB/T 2975 | GB/T 228 |
| 3 | Hardness test (Brinell hardness) | 3/batch | Different root of the rod | GB/T 231.1 |
The detection results all meet the standard requirement of Q _ XG 178-2015.
The preferred embodiments of the present invention have been described in detail, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.
It should be noted that the various technical features described in the above embodiments can be combined in any suitable manner without contradiction, and the invention is not described in any way for the possible combinations in order to avoid unnecessary repetition.
In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.
Claims (10)
1. A method for melting sulfur-containing free-cutting steel, characterized by comprising:
1) blowing the molten iron through a top-bottom combined blowing converter, and tapping;
2) hoisting the molten steel blown in the step 1) to a refining process, and refining in an LF refining furnace;
3) hoisting the molten steel refined by LF in the step 2) to a continuous casting process for full-process protective casting;
in the step 1), a converter blowing process adopts a high-tension complementary blowing mode for blowing, the content of the blown molten steel C is not more than 0.04 wt%, the content of P is not more than 0.045 wt%, and the tapping temperature is 1630-1660 ℃.
2. Smelting method according to claim 1, wherein in step 1), aluminum iron, sulfur iron, alloys and slag are added to the ladle in sequence while tapping 1/4; wherein the addition amount of the aluminum iron is 2.3-2.5kg/t, the addition amount of the sulfur iron is 8.0-8.5kg/t, the addition amount of the silicon manganese is 2.3-2.5kg/t, and the balance is supplemented with low-carbon ferromanganese to ensure that the content of Mn is 1.10-1.20 wt% when LF enters the station; the slag charge is 3.0-3.3kg/t lime.
3. The smelting method according to claim 1, wherein in step 1), argon is bottom-blown to the ladle throughout the process, based on the fact that molten steel does not splash into the ladle; after steel tapping is finished, the flow of bottom blowing argon is adjusted to the position of 500mm of the bright surface of 300-.
4. Smelting process according to claim 1, wherein in step 1) the tapping process strictly prohibits tapping.
5. The smelting method according to claim 1, wherein in the step 2), the molten steel smelting composition is: 0.05 to 0.09 weight percent of C, 0.01 to 0.03 weight percent of Si, 0.045 to 0.055 weight percent of P, 1.25 to 1.35 weight percent of Mn, 0.35 to 0.40 weight percent of S, and the weight ratio of Mn to S is 3 to 5: 1.
6. the smelting method according to claim 1, wherein in the step 2), lime 1.5-2.5kg/t and calcium carbide 0.38-0.40kg/t are added after molten steel enters a station, ferrosilicon powder can be floated on the slag surface in the electrifying process to control the oxygen balance of the slag, and the binary alkalinity of the refining slag is 2.5-3.0.
7. Smelting process according to claim 1, wherein in step 2), oxygen is controlled throughout the refining process, and oxygen is determined using a Heliothis oximeter; when the oxygen content of the molten steel is higher than 60PPm, adding aluminum iron or feeding silicon barium lines to reduce the oxygen content of the molten steel; when the oxygen content of the molten steel is lower than 40PPm, adjusting the bottom blowing flow of the steel ladle, adding iron scale and increasing the oxygen content of the molten steel; when the oxygen content of the molten steel is 40-55PPm, the molten steel is not treated.
8. Smelting process according to claim 1, wherein in step 2), calcium treatment is prohibited, soft blowing time: the soft blowing time of the first furnace for casting is not less than 15min, and the soft blowing time of the following continuous casting furnace is not less than 10 min.
9. The smelting method according to claim 1, wherein in step 3), the continuous casting protection pouring adopts a ladle-to-ladle sleeve argon blowing protection and integral nozzle casting mode, the degree of superheat of a ladle in the first furnace is 35-45 ℃, and the degree of superheat of a ladle in the continuous casting heat is 30-40 ℃.
10. A sulfur-containing free-cutting steel, characterized in that it is obtained by melting according to the melting method of any one of claims 1 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911303966.1A CN110904395A (en) | 2019-12-17 | 2019-12-17 | Sulfur-containing free-cutting steel and smelting method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911303966.1A CN110904395A (en) | 2019-12-17 | 2019-12-17 | Sulfur-containing free-cutting steel and smelting method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110904395A true CN110904395A (en) | 2020-03-24 |
Family
ID=69826103
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911303966.1A Pending CN110904395A (en) | 2019-12-17 | 2019-12-17 | Sulfur-containing free-cutting steel and smelting method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110904395A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111286580A (en) * | 2020-03-30 | 2020-06-16 | 芜湖新兴铸管有限责任公司 | Low-carbon tellurium-containing high-sulfur free-cutting steel casting blank and production method thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101580912A (en) * | 2009-06-19 | 2009-11-18 | 武汉钢铁(集团)公司 | Low carbon high sulfur free-cutting steel production process |
| CN102816979A (en) * | 2012-08-27 | 2012-12-12 | 武汉钢铁(集团)公司 | Production method of low-carbon sulfur series free-cutting steel continuous casting billet |
| CN107699796A (en) * | 2017-11-17 | 2018-02-16 | 中天钢铁集团有限公司 | A kind of low-carbon compound automatic steel and its production method |
| CN110343976A (en) * | 2019-08-13 | 2019-10-18 | 建龙北满特殊钢有限责任公司 | A kind of sulfur-bearing contains phosphorus easy cutting steel and its production method |
-
2019
- 2019-12-17 CN CN201911303966.1A patent/CN110904395A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101580912A (en) * | 2009-06-19 | 2009-11-18 | 武汉钢铁(集团)公司 | Low carbon high sulfur free-cutting steel production process |
| CN102816979A (en) * | 2012-08-27 | 2012-12-12 | 武汉钢铁(集团)公司 | Production method of low-carbon sulfur series free-cutting steel continuous casting billet |
| CN107699796A (en) * | 2017-11-17 | 2018-02-16 | 中天钢铁集团有限公司 | A kind of low-carbon compound automatic steel and its production method |
| CN110343976A (en) * | 2019-08-13 | 2019-10-18 | 建龙北满特殊钢有限责任公司 | A kind of sulfur-bearing contains phosphorus easy cutting steel and its production method |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111286580A (en) * | 2020-03-30 | 2020-06-16 | 芜湖新兴铸管有限责任公司 | Low-carbon tellurium-containing high-sulfur free-cutting steel casting blank and production method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106148844B (en) | A kind of preparation method of sulfur-bearing ultralow titanium high standard bearing steel | |
| CN108330245B (en) | High-purity smelting method for stainless steel | |
| CN108393614B (en) | High-quality welding wire steel wire rod and production method thereof | |
| CN112899552B (en) | Method for controlling inclusions in ultra-low-aluminum non-oriented silicon steel | |
| CN108220530A (en) | The sublimate method of low carbon high alloy steel | |
| CN113249639B (en) | Production method for improving castability of silicon-manganese killed silicon steel | |
| CN109082588B (en) | CrMo round bar quenched and tempered steel and preparation method thereof | |
| CN112029961B (en) | Aluminum deoxidation method for nitrogen-containing super stainless steel | |
| CN112126843B (en) | 6% Mo super austenitic stainless steel and preparation method thereof | |
| CN114318154A (en) | High-cleanliness welding wire steel L-S3 and preparation method thereof | |
| CN111286580A (en) | Low-carbon tellurium-containing high-sulfur free-cutting steel casting blank and production method thereof | |
| CN110629118A (en) | Medium-low carbon industrial ultra-pure iron and production method thereof | |
| CN114540699B (en) | High-performance hot-work die steel and preparation method thereof | |
| CN110438286B (en) | Method for controlling surface cracks of continuous casting billet of welding wire steel | |
| CN111041352A (en) | External refining production method of wire rod for cutting diamond wire | |
| CN113025781B (en) | Method for producing low-carbon low-silicon ultralow-sulfur steel by adopting LF (ladle furnace) single-link process | |
| CN110904395A (en) | Sulfur-containing free-cutting steel and smelting method thereof | |
| CN111020096B (en) | Single LF (low frequency) process low-nitrogen control method for dual-phase automobile steel DP590 | |
| CN112877587A (en) | Method for smelting high-manganese TWIP steel by adopting electric arc furnace and ladle refining furnace | |
| CN109468532B (en) | Steel for transmission gear and production method thereof | |
| CN103710645B (en) | 3Cr17NiMo die steel easy to chip and preparation method of steel | |
| CN109778073B (en) | Free-cutting steel for automobile synchronizer and preparation method thereof | |
| CN110951940B (en) | Method for continuously casting nickel-based alloy by large-size round billet | |
| CN107604120B (en) | The extremely low extremely low sulphur method for making steel of phosphorus | |
| CN113430449A (en) | Smelting and continuous casting production process of sulfur-containing free-cutting steel ASTM1141 |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200324 |
|
| RJ01 | Rejection of invention patent application after publication |