CN113637909A - Structural steel for reducing length-diameter ratio of sulfide and manufacturing method - Google Patents
Structural steel for reducing length-diameter ratio of sulfide and manufacturing method Download PDFInfo
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- 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
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B1/00—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations
- B21B1/16—Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section; Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations for rolling wire rods, bars, merchant bars, rounds wire or material of like small cross-section
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
- B21B37/74—Temperature control, e.g. by cooling or heating the rolls or the product
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- 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
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/0006—Adding metallic additives
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- 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
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/0056—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00 using cored wires
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- 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
- C22C33/06—Making ferrous alloys by melting using master alloys
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- 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
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- 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
- C22C38/005—Ferrous alloys, e.g. steel alloys containing rare earths, i.e. Sc, Y, Lanthanides
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- 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
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- 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
- C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
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- 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
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Abstract
A structural steel for reducing the length-diameter ratio of sulfide and a manufacturing method thereof, belonging to the technical field of alloy structural steel. The structural steel comprises the following chemical components in parts by weight: c: 0.32 to 0.40%, Si: 0.10 to 0.80%, Mn: 1.20-1.60%, P: 0-0.020%, S: 0.035-0.075, V: 0.08-0.15, Y: 0.005-0.040%, Ca: 0.0015-0.0035% and the balance of Fe and inevitable impurities. And the inclusions are subjected to denaturation treatment by Y, Ca microalloying, and meanwhile, the increase of the length-diameter ratio of the sulfide in the rolling process is inhibited by utilizing the rolling process design, so that the good form control of the sulfide is realized. The method has the advantages that the aim of reducing the length-diameter ratio of sulfides in the structural steel is fulfilled, and the average length-diameter ratio of the sulfides can be controlled within 5.5.
Description
Technical Field
The invention belongs to the technical field of alloy structural steel, and particularly provides structural steel for reducing the length-diameter ratio of sulfide and a manufacturing method thereof, which are suitable for manufacturing automobile structural parts such as connecting rods, crankshafts, front shafts and bolts.
Background
The non-quenched and tempered structural steel has better advantages in the aspects of environmental protection and cost due to the fact that a heat treatment link is omitted, wide development and application are achieved at present, and many structural components such as connecting rods, crankshafts and the like used on automobiles at home and abroad are produced and manufactured by adopting the non-quenched and tempered steel. As good properties such as higher toughness are obtained when the non-quenched and tempered steel is used for producing bars, sulfide inclusions which are beneficial to machining and cutting are required to be introduced into the steel in order to ensure the machining performance, and the sulfide in the rolled bars is ensured to be spindle-shaped as much as possible, so that the non-quenched and tempered steel has a smaller length-diameter ratio. The control mechanism of the length-diameter ratio of the sulfide is one of hot spots of sulfide research in the field of non-quenched and tempered steel.
The length-diameter ratio of sulfide is controlled by methods such as magnesium treatment, calcium treatment, barium treatment and the like at present, but related researches are mainly in a laboratory research stage, and industrial application is relatively few. The magnesium treatment has low yield and is chemical in the magnesium alloy adding processThe reaction is relatively violent, and the industrial application is not easy to popularize. The calcium treatment process is commonly used for improving the castability of molten steel and preventing alumina inclusions with high melting point from accumulating at a nozzle to block the nozzle, at present, the research on sulfide form control by calcium treatment is also carried out, but a large amount of calcium sulfide inclusions are easily generated during the industrial calcium treatment of sulfur-containing steel, and the calcium sulfide inclusions are easy to accumulate to block the nozzle in the casting process and have obvious adverse effect on casting. Chinese patent CN 107557531B proposes a method for controlling sulfide inclusions in non-quenched and tempered steel treated by barium alloy, which is mainly characterized in that the barium alloy is added when LF refining is finished, and Al is subjected to annealing treatment2O3The inclusion denaturation is carried out, and after VD vacuum degassing, sulfide is added into molten steel to form composite sulfide taking oxide as a core, so that continuous casting and sulfide inclusion grade control are realized, and the control of the morphology and the length-diameter ratio of the sulfide is not specifically researched.
At present, the control of the sulfide inclusion form of non-quenched and tempered steel in China is mainly focused on the smelting process, and the research on the change of sulfides in the rolling/forging process is relatively less.
Disclosure of Invention
The invention aims to provide structural steel for reducing the length-diameter ratio of sulfides and a manufacturing method thereof, and solves the problem of controlling the shape and the length-diameter ratio of sulfides.
The structural steel comprises the following chemical components in parts by weight: c: 0.32 to 0.40%, Si: 0.10 to 0.80%, Mn: 1.20-1.60%, P: 0-0.020%, S: 0.035-0.075, V: 0.08-0.15, Y: 0.005-0.040%, Ca: 0.0015-0.0035% and the balance of Fe and inevitable impurities.
The component structural steel realizes the residual Al in the steel by adding Y, Ca and other microalloy elements on the basis of the components of the traditional non-quenched and tempered steel2O3The inclusion is denatured and a plurality of Y-containing oxide inclusions are formed, the Y-containing oxide inclusions can be used as sulfide core particles, and sulfide is precipitated and grown around the Y-containing oxide inclusions in the solidification process to form a sulfide-wrapped Y-containing composite inclusion.
The smelting process route of the steel of the invention is as follows: BOF converter or EAF electric furnace, LF refining, RH vacuum degassing or VD vacuum degassing, CC continuous casting, forging and cogging, and bar rolling; the alloying method during smelting comprises the following steps: and after RH or VD vacuum treatment is finished, adding the Y-containing alloy wire into the molten steel through a wire feeding machine at the linear speed of 16-20 m/min to ensure that the Y content in the molten steel is 0.005-0.040%, and then carrying out soft blowing stirring for 5-10 min. And then further feeding Ca wires to adjust the Ca content of the molten steel. After the components are adjusted in place, casting into a continuous casting billet with a large section.
After RH or VD vacuum treatment, the content of original oxide inclusion in the steel is minimized, at the moment, the Y-containing alloy wire is added into the molten steel through a wire feeding machine, so that the using amount of the Y-containing wire can be saved, and meanwhile, the original Al can be greatly reduced2O3The inclusions are denatured. And further feeding Ca wires after soft blowing, and further performing denaturation treatment on the oxide, wherein the content of the subsequently added Ca element can be properly reduced due to the early increase of the Y element, the content is controlled to be 0.0015-0.0035%, the generation of a large amount of CaS can be ensured due to the lower Ca content, and a small amount of Ca content can be contained in the subsequently generated sulfide, so that the Ca wire has an important effect on the aspect ratio control of the sulfide during subsequent rolling, and the purpose of reducing the aspect ratio of the sulfide after rolling can be achieved due to the small amount of Ca content.
After the non-quenched and tempered structural steel continuous casting slab is obtained through smelting, the continuous casting slab needs to be further subjected to a rolling method to obtain a structural steel bar with good sulfide length-diameter ratio control, and the specific rolling process comprises the following steps: heating and preserving heat of the continuous casting billet at 1180-1230 ℃ for 5-6 hours, then rolling and cogging, after cogging, performing pit cooling or furnace cooling to 20-500 ℃, then heating again to 1170-1220 ℃, preserving heat for not less than 5 hours, after heat preservation, rolling, wherein the initial rolling temperature is 1100-1180 ℃, the final rolling temperature is 850-1000 ℃, and air cooling is performed after rolling.
During rolling, the cogging and the rolling are divided into two stages, sulfide in steel is rolled into a long strip after cogging, a billet is cooled to 20-500 ℃, the billet is heated to 1170-1220 ℃ again, the temperature is kept for not less than 5 hours, at the moment, the sulfide in the steel can be broken and spheroidized on the basis of Y-containing oxide cores, and then finer sulfide inclusions can be formed during secondary rolling, meanwhile, the sulfide contains Y, Ca and other components, the deformation performance is poor, and the length-diameter ratio can be kept in a small range.
Through the components and the process control, the aim of reducing the length-diameter ratio of sulfides in the structural steel can be fulfilled, and the average length-diameter ratio of the sulfides can be controlled within 5.5.
Drawings
FIG. 1 is a graph of the morphology of typical sulfides in a steel bar obtained in example 1.
FIG. 2 is a graph of the morphology of typical sulfides in a steel bar obtained in example 2.
FIG. 3 is a graph of the morphology of typical sulfides in steel bars obtained by a comparative example.
Detailed Description
The following is a further description of the method of carrying out the present invention by way of specific examples.
Example 1:
the structural steel comprises the following chemical components in parts by weight: c: 0.34%, Si: 0.32%, Mn: 1.45%, P: 0.011%, S: 0.051%, V: 0.11%, Y: 0.015%, Ca: 0.0027 percent, and the balance of Fe and inevitable impurities.
The manufacturing process route is as follows: BOF converter, LF refining, RH vacuum stripping, CC continuous casting, forging and cogging, and bar rolling;
the alloying method during smelting comprises the following steps: after the RH vacuum treatment is finished, the Y-containing alloy is added into the molten steel through a wire feeding machine at the linear speed of 17m/min, and then soft blowing stirring is carried out for 6 min. And then further feeding Ca wires to adjust the Ca content of the molten steel.
The rolling method comprises the following steps: heating the continuous casting billet at 1200 ℃ for 5.5 hours, then rolling and cogging, after cogging, performing pit cooling or furnace cooling to 180 ℃, then heating to 1180 ℃ again, keeping the temperature for not less than 5 hours, rolling after the heat preservation is finished, wherein the initial rolling temperature is 1100-1180 ℃, the final rolling temperature is 850-1000 ℃, and air cooling after rolling.
The structural steel bars obtained were sampled and observed for typical sulfide morphology in the steel, as shown in fig. 1 for sulfide morphology in the steel, with average sulfide aspect ratio of 5.1.
Example 2:
the structural steel comprises the following chemical components in parts by weight: c: 0.39%, Si: 0.67%, Mn: 1.40%, P: 0.013%, S: 0.063%, V: 0.10%, Y: 0.033%, Ca: 0.0021 percent, and the balance of Fe and inevitable impurities.
The manufacturing process route is as follows: EAF electric furnace, LF refining, VD vacuum degassing, CC continuous casting, forging and cogging, and bar rolling;
the alloying method during smelting comprises the following steps: after the RH vacuum treatment is finished, the Y-containing alloy is added into the molten steel through a wire feeding machine at the linear speed of 19m/min, and then soft blowing stirring is carried out for 6 min. And then further feeding Ca wires to adjust the Ca content of the molten steel.
The rolling method comprises the following steps: heating the continuous casting billet at 1210 ℃ for 5.5 hours, then rolling and cogging, after cogging, performing pit cooling or furnace cooling to 25 ℃, then heating to 1180 ℃ again, keeping the temperature for not less than 5 hours, rolling after the heat preservation is finished, wherein the initial rolling temperature is 1100-1180 ℃, the final rolling temperature is 850-1000 ℃, and air cooling after rolling.
The structural steel bars obtained were sampled and observed for typical sulfide morphology in the steel, as shown in fig. 2 for sulfide morphology in the steel, with an average sulfide aspect ratio of 4.5.
Comparative example:
the comparative steel comprises the following chemical components in percentage by weight: c: 0.38%, Si: 0.44%, Mn: 1.34%, P: 0.010%, S: 0.055%, V: 0.10% and the balance of Fe and inevitable impurities.
The manufacturing process route is as follows: BOF converter, LF refining, RH vacuum degassing, CC continuous casting and bar rolling;
the rolling method comprises the following steps: and heating and insulating the continuous casting billet at 1180 ℃ for 5.5 hours, then rolling for not less than 5 hours, rolling after the insulation is finished, wherein the initial rolling temperature is 1100-1180 ℃, the final rolling temperature is 850-1000 ℃, and air cooling is carried out after rolling.
The obtained steel bars were sampled and observed for typical sulfide morphology in steel, as shown in fig. 3 for sulfide morphology in steel, with average sulfide aspect ratio of 6.8.
Claims (2)
1. A structural steel for reducing the length-diameter ratio of sulfides is characterized in that: the steel comprises the following chemical components in parts by weight: c: 0.32 to 0.40%, Si: 0.10 to 0.80%, Mn: 1.20-1.60%, P: 0-0.020%, S: 0.035-0.075, V: 0.08-0.15, Y: 0.005-0.040%, Ca: 0.0015-0.0035% and the balance of Fe and inevitable impurities.
2. A method of manufacturing the structural steel of claim 1, wherein:
the manufacturing process route is as follows: BOF converter or EAF electric furnace, LF refining, RH vacuum degassing or VD vacuum degassing, CC continuous casting, forging and cogging, and bar rolling;
the alloying method during smelting comprises the following steps: after RH or VD vacuum treatment is finished, adding the Y-containing alloy wire into the molten steel through a wire feeding machine at the linear speed of 16-20 m/min to ensure that the Y content in the molten steel is 0.005-0.040%, and then carrying out soft blowing stirring for 5-10 min; then further feeding Ca lines to adjust the Ca content of the molten steel; after the components are adjusted in place, casting into a large-section continuous casting billet;
the rolling method comprises the following steps: heating and preserving heat of the continuous casting billet at 1180-1230 ℃ for 5-6 hours, then rolling and cogging, after cogging, performing pit cooling or furnace cooling to 20-500 ℃, then heating again to 1170-1220 ℃, preserving heat for not less than 5 hours, after heat preservation, rolling, wherein the initial rolling temperature is 1100-1180 ℃, the final rolling temperature is 850-1000 ℃, and air cooling is performed after rolling.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115386797A (en) * | 2022-08-29 | 2022-11-25 | 西安建筑科技大学 | Non-quenched and tempered steel for automobile and processing method thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2018523A1 (en) * | 1989-06-09 | 1990-12-09 | Serosh Engineer | Structural steel |
| CN107287504A (en) * | 2017-06-16 | 2017-10-24 | 上海大学 | The middle carbon easy-cutting non-hardened and tempered steel and its manufacturing technique method of sulfur-bearing, tellurium |
| CN109234627A (en) * | 2018-10-17 | 2019-01-18 | 南京钢铁股份有限公司 | A kind of high-strength and high-ductility Micro Alloying round steel and preparation method |
| CN111172351A (en) * | 2020-01-17 | 2020-05-19 | 中天钢铁集团有限公司 | Control method for medium-carbon sulfur-containing aluminum deoxidized non-quenched and tempered steel Ds inclusion |
| CN112899567A (en) * | 2021-01-18 | 2021-06-04 | 中国科学院金属研究所 | High-purity high-strength-toughness rare earth free-cutting steel |
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- 2021-07-30 CN CN202110874108.3A patent/CN113637909B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2018523A1 (en) * | 1989-06-09 | 1990-12-09 | Serosh Engineer | Structural steel |
| CN107287504A (en) * | 2017-06-16 | 2017-10-24 | 上海大学 | The middle carbon easy-cutting non-hardened and tempered steel and its manufacturing technique method of sulfur-bearing, tellurium |
| CN109234627A (en) * | 2018-10-17 | 2019-01-18 | 南京钢铁股份有限公司 | A kind of high-strength and high-ductility Micro Alloying round steel and preparation method |
| CN111172351A (en) * | 2020-01-17 | 2020-05-19 | 中天钢铁集团有限公司 | Control method for medium-carbon sulfur-containing aluminum deoxidized non-quenched and tempered steel Ds inclusion |
| CN112899567A (en) * | 2021-01-18 | 2021-06-04 | 中国科学院金属研究所 | High-purity high-strength-toughness rare earth free-cutting steel |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115386797A (en) * | 2022-08-29 | 2022-11-25 | 西安建筑科技大学 | Non-quenched and tempered steel for automobile and processing method thereof |
| CN115386797B (en) * | 2022-08-29 | 2023-08-22 | 西安建筑科技大学 | Non-quenched and tempered steel for automobiles and processing method thereof |
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