CN116790993A - Production and preparation method of high-aluminum plastic die steel - Google Patents

Production and preparation method of high-aluminum plastic die steel Download PDF

Info

Publication number
CN116790993A
CN116790993A CN202310795397.7A CN202310795397A CN116790993A CN 116790993 A CN116790993 A CN 116790993A CN 202310795397 A CN202310795397 A CN 202310795397A CN 116790993 A CN116790993 A CN 116790993A
Authority
CN
China
Prior art keywords
steel
temperature
equal
pass
percent
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
Application number
CN202310795397.7A
Other languages
Chinese (zh)
Inventor
张群
卢秉军
王德勇
阚开
赵千水
齐峰
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Bengang Steel Plates Co Ltd
Original Assignee
Bengang Steel Plates Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Bengang Steel Plates Co Ltd filed Critical Bengang Steel Plates Co Ltd
Priority to CN202310795397.7A priority Critical patent/CN116790993A/en
Publication of CN116790993A publication Critical patent/CN116790993A/en
Pending legal-status Critical Current

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
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D7/00—Casting ingots, e.g. from ferrous metals
    • 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
    • C21C5/52—Manufacture of steel in electric furnaces
    • 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
    • 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
    • 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
    • C21C7/0075—Treating in a ladle furnace, e.g. up-/reheating of molten steel within the ladle
    • 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
    • C21C7/04—Removing impurities by adding a treating agent
    • C21C7/06—Deoxidising, e.g. killing
    • 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
    • C21C7/10—Handling in a vacuum
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/18—Hardening; Quenching with or without subsequent tempering
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/002—Heat treatment of ferrous alloys containing Cr
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/004—Heat treatment of ferrous alloys containing Cr and Ni
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/005—Heat treatment of ferrous alloys containing Mn
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D6/00—Heat treatment of ferrous alloys
    • C21D6/008—Heat treatment of ferrous alloys containing Si
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/06—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of rods or wires
    • C21D8/065—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of rods or wires of ferrous alloys
    • 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
    • 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
    • C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
    • 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
    • C22C38/20—Ferrous alloys, e.g. steel alloys containing chromium with copper
    • 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
    • C22C38/22—Ferrous alloys, e.g. steel alloys containing chromium with molybdenum or tungsten
    • 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
    • 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
    • C22C38/44—Ferrous alloys, e.g. steel alloys containing chromium with nickel with molybdenum or tungsten

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Treatment Of Steel In Its Molten State (AREA)

Abstract

The invention discloses a production and preparation method of high-aluminum plastic die steel, which comprises the following chemical components in percentage by mass: 0.36% -0.40%, si:0.25 to 0.35 percent, mn:0.32% -0.50%, P: less than or equal to 0.012 percent, S: less than or equal to 0.006 percent, cr:1.37 to 1.55 percent of Ni: less than or equal to 0.25 percent, mo:0.16 to 0.23 percent, cu: less than or equal to 0.015 percent, al:0.80% -1.00%, and the balance of iron and unavoidable impurities. The invention adopts the electric furnace smelting-external refining (LF+VD) -die casting ingot smelting process, thereby ensuring the indexes such as the low-power structure, nonmetallic inclusion, gas content and the like of the finished steel of the high-aluminum plastic die steel.

Description

Production and preparation method of high-aluminum plastic die steel
Technical Field
The invention relates to the field of special steel, in particular to a production and preparation method of high-aluminum plastic die steel.
Background
As plastic products are increasingly used in industry and daily life, the demand for die steel in the plastic die industry is also increasing. In the plastic molding process, the quality of the mold plays a self-evident role in ensuring the quality of the product. The plastic mold has been developed in the directions of precision, large-scale and multi-cavity, and the requirements on the performance of the plastic mold steel are higher and higher, and the performance of the plastic mold steel is determined according to the requirements of the type of plastic, the application of products, the production batch, the dimensional precision and the surface quality.
Therefore, it is necessary to develop high aluminum plastic mold steel with high strength, impact toughness and high steel purity, which meets the requirements of high-end products.
Disclosure of Invention
The invention aims to provide a production and preparation method of high-aluminum plastic die steel 38CrMoAlA, which adopts an electric furnace smelting-external refining (LF+VD) -die ingot smelting process to produce and manufacture the high-aluminum plastic die steel 38CrMoAlA, realizes the breakthrough of mass production of high-quality high-aluminum plastic die steel 38CrMoAlA in an electric furnace process, ensures indexes such as low-power tissues, nonmetallic inclusion, gas content and the like of finished steel products of the high-aluminum plastic die steel 38CrMoAlA, ensures the mechanical properties of the high-aluminum plastic die steel 38CrMoAlA, has high strength, impact toughness and high steel purity, meets the requirements of high-end products, and fills up the blank of a high-aluminum plastic die steel market.
In order to achieve the aim of the invention, the invention provides a production and preparation method of high-aluminum plastic die steel 38CrMoAlA, which comprises the following specific steps of: electric furnace smelting, external refining (LF+VD), die casting, soaking furnace heating process, high-pressure water descaling, rolling and slow cooling (heat preservation). Meets the quality requirement of the high-aluminum plastic die steel 38CrMoAlA, and the indexes of the low-power structure, nonmetallic inclusion, mechanical property and the like can also meet the standard requirement.
The high-aluminum plastic die steel 38CrMoAlA comprises the following chemical components in percentage by mass: 0.36% -0.40%, si:0.25 to 0.35 percent, mn:0.32% -0.50%, P: less than or equal to 0.012 percent, S: less than or equal to 0.006 percent, cr:1.37 to 1.55 percent of Ni: less than or equal to 0.25 percent, mo:0.16 to 0.23 percent, cu: less than or equal to 0.015 percent, al:0.80% -1.00%, and the balance of iron and unavoidable impurities.
In order to ensure the purity of the steel, the oxygen content of the steel is less than or equal to 15 multiplied by 10 -6 The nitrogen content is less than or equal to 70 multiplied by 10 -6 The hydrogen content is less than or equal to 2 multiplied by 10 -6 。
A production and preparation method of high-aluminum plastic die steel 38CrMoAlA comprises the following steps: electric furnace smelting, external refining (LF+VD), die casting, soaking furnace heating process, high-pressure water descaling, rolling process and slow cooling;
wherein, the electric furnace smelting is as follows: smelting by adopting 65-75% of molten iron and 25-35% of scrap steel; heating up the three-phase electrode, oxidizing with oxygen, boiling, automatically flowing slag, tapping at 1660-1665 ℃, wherein C is 0.10-0.15% during tapping, P is less than or equal to 0.008%, and adding auxiliary materials and alloy during tapping 1/4-1/3. Alloy ton steel addition: 0.06-0.07 Kg/t of aluminum ingot, 3.1-3.3 Kg/t of high carbon ferromanganese and 17-18 Kg/t of high carbon ferrochrome. The addition amount of auxiliary materials per ton of steel is as follows: 6.5-7 Kg/t of electric furnace foaming agent and 42-43 Kg/t of active lime.
The LF furnace refining is as follows: the 21000-22000A high-current heating slag melting is adopted, the refining time is 160-165 min, when the slag surface fluctuates, molten steel and electric arc are not exposed, active lime is added, after 5min, the chemical components are sampled and analyzed for the first time, the alloy is added according to the target value of the chemical components, and the alloy is added to argon gas flow to promote the rapid melting and homogenization of the alloy. When the temperature of molten steel reaches 1580-1589 ℃, adding a diffusion deoxidizer for diffusion deoxidization, and when the temperature of molten steel reaches 1630-1635 ℃, sampling and analyzing chemical components for the second time to confirm the deviation value of the content of each chemical element component from the target value, taking out the secondary sample, adding the diffusion deoxidizer, and continuously adjusting slag. The adding amount of the additional alloy ton steel is as follows: 1.1 to 1.2kg/t of ferrosilicon, 3.3 to 3.5kg/t of high carbon ferrochrome, 8.8 to 9kg/t of aluminum ingot and 2.4 to 2.6kg/t of ferromolybdenum. And simultaneously continuously maintaining the white slag to be smelted for 25-30 min. Slag sample binary alkalinity (CaO/SiO) after LF refining 2 ) Ensure R1 is more than or equal to 9.0, and the ternary alkalinity ((CaO+MgO)/SiO) 2 ) Ensure R2 is more than or equal to 10, and quaternary basicity ((CaO+MgO)/(SiO) 2 +Al 2 O 3 ) And R3 is more than or equal to 1.5.
The VD refining is as follows: the temperature before VD is 1680-1685 ℃, the argon pressure is controlled to be 0.1-0.3 MPa before a vacuum pump is started, the slag surface micro-motion molten steel is not exposed, the timing is started when the vacuum degree reaches 100-110 Pa, the holding time is 20-25 min, the vacuum breaking temperature is 1615-1620 ℃, alloy is added according to the molten steel component reference target component, the argon pressure is regulated to be 0.3-0.5 MPa, the static argon blowing time is 30-35 min, the phi 10mm silicon-calcium cored wire is added for 2.2-2.3 m/t steel after the static argon blowing is finished, the hanging package temperature is 1600-1610 ℃, and the carbonized rice husk is 1.7-1.8 kg/t steel.
The die casting is as follows: pouring a steel ingot of 0.6-8.4t, after molten steel is poured onto a cap opening for 20-30 mm, starting gradual flow reduction to perform slow pouring, after pouring the molten steel onto one half of the pouring height of the cap opening, closing a sliding plate to stop pouring for 6-8S, and then performing rapid flow opening and pouring for a plurality of times, wherein the interval time is about 4-5S each time, and the heat insulating agent coke powder of the cap opening is added when the pouring height reaches 2/3 of the height of the cap opening.
Further, in the die casting step, 2 ingot plates are cast, and each plate is provided with 6 steel ingots of 3.16 t; the casting time of single-disc die casting is strictly controlled, the spindle body is 6-6.5 min, and the cap opening is 6-6.5 min.
Further, in the die casting step, the cap mouth heat preservation agent coke powder is added when the cap mouth heat preservation agent coke powder is injected to the height of 2/3 of the cap mouth, and the adding amount is 10-12Kg/t of steel ingot.
Further, the heating process comprises the following steps: the ingot temperature is 600-850 ℃ when the soaking pit is arranged, the preheating section requirement of the soaking pit is designed according to the characteristics of the 38CrMoAlA steel grade, the heating time is more than or equal to 1h, and the temperature is increased to 950-960 ℃; the heating section is heated to 1200-1220 ℃ with the temperature rising speed less than or equal to 180/h, the temperature rising time more than or equal to 2.5h, the temperature rising is carried out to 1200-1220 ℃ with the temperature equalizing time of 1.5-2 h.
Further, the high-pressure water descaling is as follows: the dephosphorization water adopts turbid circulating water, and the water spraying pressure is 20-30MPa.
Further, the steel has a production specification of Φ50-200mm, preferably 110mm.
Further, the rolling process comprises blooming and continuous rolling, and the blooming rolling and continuous rolling unit is used 1150, specifically: BD cogging process: cogging by adopting a 1150mm BD blooming mill, rolling for 11 passes, and reducing: 80 to 80.5mm of the 1 st pass, 80 to 80.5mm of the 2 nd pass, 95 to 95.5mm of the 3 rd pass, 85 to 85.5mm of the 4 th pass, 72 to 72.5mm of the 5 th pass, 82 to 82.5mm of the 6 th pass, 69 to 69.5mm of the 7 th pass, 75 to 75.5mm of the 8 th pass, 32 to 32.5mm of the 9 th pass, 20 to 20.5mm of the 10 th pass, 32 to 32.5mm of the 11 th pass, and then a large rod is discharged through a 3-frame 850mm rolling mill and enters a continuous rolling unit.
Further, the initial rolling temperature of the steel is 1100-1130 ℃; finish rolling temperature is 950 ℃ to 1100 ℃; the finishing temperature is 850-920 ℃.
Further, the heat preservation process comprises the following steps: the temperature of the lower heat preservation pit is more than or equal to 600 ℃, the heat preservation is carried out for 48-60h, and the temperature of the pit outlet is less than or equal to 130 ℃.
Based on the technical scheme, further, the heat-preserving steel material is sampled and subjected to heat treatment, and the heat treatment comprises the following steps:
1) Quenching: preserving heat for 50-70min at 930-950 ℃ and cooling with oil;
2) Tempering: heat preservation is carried out for 110-130min at 635-645 ℃ and water cooling is carried out.
The invention has the beneficial effects that:
(1) The high-aluminum plastic die steel 38CrMoAlA is produced by adopting an electric furnace smelting-external refining (LF+VD) -die ingot smelting process and a rolling process, and round steel with the specification of phi 110mm is produced, so that the purity of the steel is ensured.
(2) Reasonable component design and production process ensure the surface quality.
(3) The low-power structure, nonmetallic inclusion, gas content and mechanical property of the finished steel meet the requirements of high-end products.
Detailed Description
The following non-limiting examples will enable those of ordinary skill in the art to more fully understand the invention and are not intended to limit the invention in any way.
Example 1
1 component optimization design
(1) In order to meet the requirement of the high-aluminum plastic die steel 38CrMoAlA, the internal control chemical components are determined, and the mass percentages of the internal control chemical components are C:0.38%, si:0.28%, mn:0.36%, P:0.010%, S:0.005%, cr:1.40%, ni:0.10%, mo:0.19%, cu:0.01%, al:0.90%, the balance being iron and unavoidable impurities.
(2) In order to ensure the purity of the steel, the oxygen content of the steel is required to be 13 multiplied by 10 -6 Nitrogen content 60×10 -6 Hydrogen content 1.5X10 -6 。
2 high-aluminum plastic die steel 38CrMoAlA electric furnace die casting production process parameter design
The process route is as follows: 50t electric furnace smelting, external refining (LF+VD), 3.16t die casting, soaking furnace heating, high-pressure water descaling, 1150 blooming mill rolling, continuous rolling unit and slow cooling; wherein:
(1) An electric furnace smelting process comprises the following steps: smelting by adopting 70% molten iron and 30% scrap steel in mass fraction; three-phase electrode temperature rise, oxygen oxidation, violent boiling and automatic slag flowing, tapping temperature 1662 ℃, C0.12% during tapping, P:0.006%, adding auxiliary materials and alloy when tapping 1/4. Alloy ton steel addition: aluminum ingot 0.06Kg/t, high carbon ferromanganese 3.2Kg/t, high carbon ferrochrome 17Kg/t. The addition amount of auxiliary materials is as follows: 6.8Kg/t of electric furnace foaming agent and 42Kg/t of active lime.
(2) LF furnace: the 21000A high-current heating slag melting is adopted, the refining time is 162min, when the slag surface fluctuates, molten steel and electric arc are not exposed, active lime is added, after 5min, the chemical components are sampled and analyzed for the first time, the alloy is added according to the target value of the chemical components, and the alloy is added to argon gas flow so as to promote the rapid melting and homogenization of the alloy. When the temperature of molten steel reaches 1585 ℃, adding a diffusion deoxidizer for diffusion deoxidization, and when the temperature of molten steel reaches 1632 ℃, sampling and analyzing chemical components for the second time to confirm the deviation value of the content of each chemical element component from the target value, and after taking out the secondary sample, adding the diffusion deoxidizer for continuous slag adjustment. And (3) adding alloy: 1.1kg/t of ferrosilicon, 3.3kg/t of high-carbon ferrochromium, 8.8kg/t of aluminum ingot and 2.4kg/t of ferromolybdenum. And simultaneously continuously maintaining the white slag smelting for 26min. After LF, the binary alkalinity (CaO/SiO 2) of the slag sample ensures R1:9.5, ternary basicity ((CaO+MgO)/SiO) 2 ) Guarantee R2:10.2, quaternary basicity ((CaO+MgO)/(SiO) 2 +Al 2 O 3 ) Guaranteed R3:1.8.
(3) And (3) VD refining: the temperature before VD is 1682 ℃, the argon pressure is controlled to be 0.15MPa before a vacuum pump is started, the slag surface micro-motion molten steel is not exposed, the timing is started when the vacuum degree reaches 100Pa, the holding time is 25min, the vacuum breaking temperature is 1618 ℃, alloy is added according to the molten steel components, meanwhile, the argon pressure is adjusted to be 0.3MPa, the static argon blowing time is 32min, after the static argon blowing is finished, the phi 10mm calcium silicate cored wire is added to be 2.2m/t, the hanging package temperature is 1605 ℃, and the carbonized rice husk is 1.7kg/t.
(4) And (3) die casting: and pouring 2 ingot plates, wherein each plate is provided with 6 steel ingots of 3.16t, after molten steel is poured onto a cap opening for 20mm, gradually reducing flow is started to perform slow pouring, after the molten steel is poured onto one half of the pouring height of the cap opening, a sliding plate is closed to stop pouring for 7S, and then pouring is performed through multiple rapid open flow pouring, the interval time is about 4S each time, and the heat insulating agent coke powder at the cap opening is added when the pouring height reaches 2/3 of the height of the cap opening. The casting time of single-disc die casting is strictly controlled, the spindle body is 6min, and the cap opening is 6min.
(5) The heating process comprises the following steps: the ingot temperature is 720 ℃ when the soaking pit is arranged, the preheating section requirement of the soaking pit is designed according to the characteristics of the 38CrMoAlA steel grade, the heating time is 1.5h, and the temperature is increased to 950 ℃; the heating section is heated to the temperature rising speed of 1200 ℃ for 150/h, the heating time is 3h, the heating section is heated to 1220 ℃, and the temperature is equalized for 2h.
(6) High-pressure water descaling: the dephosphorization water adopts turbid circulating water, and the water spraying pressure is 28MP.
(7) The rolling process comprises the following steps: the rolling process of the product specification phi 110mm comprises the following steps:
the initial rolling temperature of the steel is 1100 ℃; finish rolling temperature 980 ℃; the finishing temperature is 870 ℃.
BD cogging process: cogging by adopting a 1150mm BD blooming mill, rolling for 11 passes, and reducing: 80mm in 1 st pass, 80mm in 2 nd pass, 95mm in 3 rd pass, 85mm in 4 th pass, 72mm in 5 th pass, 82mm in 6 th pass, 69mm in 7 th pass, 75mm in 8 th pass, 32mm in 9 th pass, 20mm in 10 th pass, 32mm in 11 th pass and a large bar continuous rolling unit is obtained through a 3-frame 850mm rolling mill.
(8) The heat preservation process comprises the following steps: the temperature of the lower heat preservation pit is 700 ℃, the heat preservation is carried out for 48 hours, and the temperature of the pit outlet is 110 ℃.
Example 2
1 component optimization design
(1) In order to meet the requirement of the high-aluminum plastic die steel 38CrMoAlA, the internal control chemical components are determined, and the mass percentages of the internal control chemical components are C:0.37%, si:0.29%, mn:0.38%, P:0.010%, S:0.005%, cr:1.42%, ni:0.10%, mo:0.18%, cu:0.010%, al:0.85%, the balance being iron and unavoidable impurities.
(2) In order to ensure the purity of the steel, the oxygen content of the steel is 11 multiplied by 10 -6 Nitrogen content 65×10 -6 Hydrogen content 1.6X10 -6 。
2 high-aluminum plastic die steel 38CrMoAlA electric furnace die casting production process parameter design
The process route is as follows: 50t electric furnace smelting, external refining (LF+VD), 3.16t die casting, soaking furnace heating, high-pressure water descaling, 1150 blooming mill rolling, continuous rolling unit and slow cooling; wherein:
(1) An electric furnace smelting process comprises the following steps: smelting by adopting 68% molten iron and 32% scrap steel in mass fraction; three-phase electrode temperature rise, oxygen oxidation, violent boiling and automatic slag flowing, tapping temperature 1660 ℃, C0.10% during tapping, P:0.007 percent, and adding auxiliary materials and alloy when tapping 1/4. Alloy ton steel addition: aluminum ingot 0.06Kg/t, high carbon ferromanganese 3.1Kg/t, high carbon ferrochrome 17Kg/t. The addition amount of auxiliary materials is as follows: 6.6Kg/t of electric furnace foaming agent and 42Kg/t of active lime.
(2) LF furnace: the 21000A high-current heating slag melting is adopted, the refining time is 162min, when the slag surface fluctuates, molten steel and electric arc are not exposed, active lime is added, after 5min, the chemical components are sampled and analyzed for the first time, the alloy is added according to the target value of the chemical components, and the alloy is added to argon gas flow so as to promote the rapid melting and homogenization of the alloy. When the temperature of molten steel reaches 1585 ℃, adding a diffusion deoxidizer for diffusion deoxidization, and when the temperature of molten steel reaches 1634 ℃, sampling and analyzing chemical components for the second time to confirm the deviation value of the content of each chemical element component from the target value, and after taking out the secondary sample, adding the diffusion deoxidizer for continuous slag adjustment. And (3) adding alloy: 1.1kg/t of ferrosilicon, 3.3kg/t of high-carbon ferrochromium, 8.8kg/t of aluminum ingot and 2.5kg/t of ferromolybdenum. And simultaneously continuously maintaining the white slag smelting for 26min. Binary basicity (CaO/SiO) of slag sample after LF 2 ) Guarantee R1:9.2, ternary basicity ((CaO+MgO)/SiO) 2 Guarantee R2:10.6, quaternary basicity ((CaO+MgO)/(SiO2+Al) 2 O 3 ) Guarantee R3:1.8.
(3) And (3) VD refining: the temperature before VD is 1682 ℃, the argon pressure is controlled to be 0.1MPa before a vacuum pump is started, the slag surface micro-movement of molten steel is not exposed, the timing is started when the vacuum degree reaches 100Pa, the holding time is 20-25 min, the vacuum breaking temperature is 1618 ℃, alloy is added according to the molten steel components, meanwhile, the argon pressure is adjusted to be 0.3MPa, the static argon blowing time is 33min, after the static argon blowing is finished, the phi 10mm calcium silicate cored wire is added to be 2.2m/t, the hanging package temperature is 1600 ℃, and the carbonized rice husk is 1.7kg/t.
(4) And (3) die casting: and 2 ingot plates are cast, each plate is provided with 6 steel ingots of 3.16t, after molten steel is cast to a cap opening by 24mm, gradually reducing flow is started to perform slow casting, after casting is performed to one half of the casting height of the cap opening, a sliding plate is closed to stop casting for 6S, and after the casting is stopped, the pouring is performed for a plurality of times by rapid flow opening and flushing, the interval time is about 4S each time until the casting height and the filling time are reached, and the cap opening heat insulating agent coke powder is added when the pouring is performed to the 2/3 of the height of the cap opening. The casting time of single-disc die casting is strictly controlled, the spindle body is 6min, and the cap opening is 6min.
(5) The heating process comprises the following steps: the ingot temperature is 700 ℃ when the soaking pit is arranged, the preheating section requirement of the soaking pit is designed according to the characteristics of the 38CrMoAlA steel grade, the heating time is 1.3h, and the temperature is increased to 950 ℃; the heating section is heated to 1220 ℃ with the temperature rising speed of 130/h and the temperature rising time of 3h, and the temperature rising time is heated to 1220 ℃ with the uniform temperature of 1.8h.
(6) High-pressure water descaling: the dephosphorization water adopts turbid circulating water, and the water spraying pressure is 28MP.
(7) The rolling process comprises the following steps: the rolling process of the product specification phi 110mm comprises the following steps:
the initial rolling temperature of the steel is 1110 ℃; finish rolling temperature 990 ℃; the finishing temperature was 880 ℃.
BD cogging process: cogging by adopting a 1150mm BD blooming mill, rolling for 11 passes, and reducing: 80mm in 1 st pass, 80mm in 2 nd pass, 95mm in 3 rd pass, 85mm in 4 th pass, 72mm in 5 th pass, 82mm in 6 th pass, 69mm in 7 th pass, 75mm in 8 th pass, 32mm in 9 th pass, 20mm in 10 th pass, 32mm in 11 th pass and a large bar continuous rolling unit is obtained through a 3-frame 850mm rolling mill.
(8) The heat preservation process comprises the following steps: the temperature of the lower heat preservation pit is 700 ℃, the heat preservation is carried out for 48 hours, and the temperature of the pit outlet is 90 ℃.
Example 3
1 component optimization design
(1) In order to meet the requirement of the high-aluminum plastic die steel 38CrMoAlA, the internal control chemical components are determined, and the mass percentages of the internal control chemical components are C:0.37%, si:0.26%, mn:0.38%, P:0.011%, S:0.005%, cr:1.43%, ni:0.10%, mo:0.18%, cu:0.010%, al:0.90%, the balance being iron and unavoidable impurities.
(2) In order to ensure the purity of the steel, the oxygen content of the steel is required to be 12 multiplied by 10 -6 Nitrogen content 60×10 -6 Hydrogen content 1.5X10 -6 。
2 high-aluminum plastic die steel 38CrMoAlA electric furnace die casting production process parameter design
The process route is as follows: 50t electric furnace smelting, external refining (LF+VD), 3.16t die casting, soaking furnace heating, high-pressure water descaling, 1150 blooming mill rolling, continuous rolling unit and slow cooling; wherein:
(1) An electric furnace smelting process comprises the following steps: smelting by adopting 65% molten iron and 35% scrap steel in mass fraction; three-phase electrode temperature rise, oxygen oxidation, violent boiling and automatic slag flowing, tapping temperature 1665 ℃, C0.12% during tapping, P:0.007 percent, and adding auxiliary materials and alloy when tapping 1/4. Alloy ton steel addition: aluminum ingot 0.06Kg/t, high carbon ferromanganese 3.2Kg/t, high carbon ferrochrome 17Kg/t. The addition amount of auxiliary materials is as follows: 6.6Kg/t of electric furnace foaming agent and 42Kg/t of active lime.
(2) LF furnace: the 21000A high-current heating slag melting is adopted, the refining time is 162min, when the slag surface fluctuates, molten steel and electric arc are not exposed, active lime is added, after 5min, the chemical components are sampled and analyzed for the first time, the alloy is added according to the target value of the chemical components, and the alloy is added to argon gas flow so as to promote the rapid melting and homogenization of the alloy. When the temperature of molten steel reaches 1585 ℃, adding a diffusion deoxidizer for diffusion deoxidization, and when the temperature of molten steel reaches 1630 ℃, sampling and analyzing chemical components for the second time to confirm the deviation value of the content of each chemical element component from the target value, and after taking out the secondary sample, adding the diffusion deoxidizer for continuous slag adjustment. And (3) adding alloy: 1.1kg/t of ferrosilicon, 3.3kg/t of high-carbon ferrochromium, 8.9kg/t of aluminum ingot and 2.5kg/t of ferromolybdenum. And simultaneously continuously maintaining the white slag to be smelted for 25min. Binary basicity (CaO/SiO) of slag sample after LF 2 ) Guarantee R1:9.5, ternary basicity ((CaO+MgO)/SiO) 2 Guarantee R2:10.5, quaternary basicity ((CaO+MgO)/(SiO) 2 +Al 2 O 3 ) Guarantee R3:1.8.
(3) And (3) VD refining: the temperature before VD is 1682 ℃, the argon pressure is controlled to be 0.1MPa before a vacuum pump is started, the slag surface micro-movement of molten steel is not exposed, the timing is started when the vacuum degree reaches 100Pa, the holding time is 20-25 min, the vacuum breaking temperature is 1618 ℃, alloy is added according to the molten steel components, meanwhile, the argon pressure is adjusted to be 0.4MPa, the static argon blowing time is 32min, after the static argon blowing is finished, the phi 10mm calcium silicate cored wire is added to be 2.2m/t, the hanging package temperature is 1605 ℃, and the carbonized rice husk is 1.7kg/t.
(4) And (3) die casting: and 2 ingot trays are cast, each tray is provided with 6 steel ingots of 3.16t, after molten steel is cast to a cap opening by 20-30 mm, gradually reducing flow is started to perform slow casting, after casting is performed to one half of the casting height of the cap opening, a sliding plate is closed to stop casting for 6S, and after the casting is stopped, the rapid flow opening and pouring are performed for a plurality of times, the interval time is about 4S each time, until the casting height and the filling time are reached, and the heat insulating agent coke powder at the cap opening is added when the casting is performed to the 2/3 height of the cap opening. The casting time of single-disc die casting is strictly controlled, the spindle body is 6min, and the cap opening is 6min.
(5) The heating process comprises the following steps: the ingot temperature is 750 ℃ when the soaking pit is arranged, the preheating section requirement of the soaking pit is designed according to the characteristics of the 38CrMoAlA steel grade, the heating time is 1.2h, and the temperature is increased to 950 ℃; the heating section is heated to 1220 ℃ with the temperature rising speed of 150/h and the temperature rising time of 3h, and the temperature rising time is heated to 1220 ℃ with the temperature equalizing time of 2h.
(6) High-pressure water descaling: the dephosphorization water adopts turbid circulating water, and the water spraying pressure is 28MP.
(7) The rolling process comprises the following steps: the rolling process of the product specification phi 110mm comprises the following steps:
the initial rolling temperature of the steel is 1100 ℃; finish rolling temperature 980 ℃; the finishing temperature was 880 ℃.
BD cogging process: cogging by adopting a 1150mm BD blooming mill, rolling for 11 passes, and reducing: 80mm in 1 st pass, 80mm in 2 nd pass, 95mm in 3 rd pass, 85mm in 4 th pass, 72mm in 5 th pass, 82mm in 6 th pass, 69mm in 7 th pass, 75mm in 8 th pass, 32mm in 9 th pass, 20mm in 10 th pass, 32mm in 11 th pass and a large bar continuous rolling unit is obtained through a 3-frame 850mm rolling mill.
(8) The heat preservation process comprises the following steps: the temperature of the lower heat preservation pit is 700 ℃, the heat preservation is carried out for 48 hours, and the temperature of the pit outlet is 120 ℃.
Examples 1 to 3 results of the final product inspection
(1) Low-power structure of steel
Sequence number General porosity Center porosity Ingot segregation General spot segregation Edge spot segregation
Standard of ≤2.0 ≤2.0 ≤2.0 ≤1.0 ≤1.0
Example 1 0.5 0.5 0.5 0 0
Example 1 0.5 0.5 0.5 0 0
Example 2 0.5 0.5 0.5 0 0
Example 2 0.5 0.5 0.5 0 0
Example 3 0.5 0.5 0.5 0 0
Example 3 0.5 0.5 0.5 0 0
(2) Nonmetallic inclusion of steel
(3) Mechanical properties of steel
Many possible variations and modifications of the disclosed technology can be made by anyone skilled in the art without departing from the scope of the technology, or the technology can be modified to be equivalent. Therefore, any simple modification, equivalent variation and modification of the above embodiments according to the technical substance of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims (10)

1. The high-aluminum plastic die steel is characterized by comprising the following chemical components in percentage by mass: 0.36% -0.40%, si:0.25 to 0.35 percent, mn:0.32% -0.50%, P: less than or equal to 0.012 percent, S: less than or equal to 0.006 percent, cr:1.37 to 1.55 percent of Ni: less than or equal to 0.25 percent, mo:0.16 to 0.23 percent, cu: less than or equal to 0.015 percent, al:0.80% -1.00%, and the balance of iron and unavoidable impurities.
2. The high-alumina plastic mold steel according to claim 1, wherein the oxygen content of the steel is 15 x 10 or less -6 The nitrogen content is less than or equal to 70 multiplied by 10 -6 The hydrogen content is less than or equal to 2 multiplied by 10 -6 。
3. A method of producing the high aluminum plastic mold steel as claimed in claim 1 or 2, characterized in that the method comprises: smelting in an electric furnace, refining outside an LF+VD furnace, die casting, heating, descaling by high-pressure water, rolling and heat preservation;
wherein, the electric furnace smelting is as follows: smelting by adopting 65-75% of molten iron and 25-35% of scrap steel; heating a three-phase electrode, oxidizing by oxygen, boiling, automatically flowing slag, tapping at 1660-1665 ℃, wherein C is 0.10-0.15% during tapping, P is less than or equal to 0.008%, and adding auxiliary materials and alloy during tapping 1/4-1/3; alloy ton steel addition: 0.06-0.07 kg/t of aluminum ingot, 3.1-3.3 kg/t of high carbon ferromanganese and 17-18 kg/t of high carbon ferrochrome; the addition amount of auxiliary materials per ton of steel is as follows: 6.5-7 kg/t of electric furnace foaming agent and 42-43 kg/t of active lime;
the LF refining is as follows: adopting 21000-22000A high-current heating to melt slag, refining for 160-165 min, adding active lime when slag surface fluctuates and molten steel and electric arc are not exposed, and after 5minAnalyzing chemical components by sampling for the first time, and supplementing alloy according to a chemical component target value; adding a diffusion deoxidizer when the temperature of molten steel reaches 1580-1589 ℃, performing diffusion deoxidization, and sampling and analyzing chemical components for the second time when the temperature of molten steel reaches 1630-1635 ℃ to confirm the deviation value of the content of each chemical element from the target value, and supplementing the diffusion deoxidizer to continuously adjust slag after taking out the secondary sample; the adding amount of the additional alloy ton steel is as follows: 1.1 to 1.2kg/t of ferrosilicon, 3.3 to 3.5kg/t of high carbon ferrochromium, 8.8 to 9kg/t of aluminum ingot and 2.4 to 2.6kg/t of ferromolybdenum; simultaneously continuously maintaining the white slag to be smelted for 25-30 min; slag sample binary alkalinity (CaO/SiO) after LF refining 2 ) Ensure R1 is more than or equal to 9.0, and the ternary alkalinity ((CaO+MgO)/SiO) 2 ) Ensure R2 is more than or equal to 10, and quaternary basicity ((CaO+MgO)/(SiO) 2 +Al 2 O 3 ) Ensuring R3 is more than or equal to 1.5;
the VD refining is as follows: the temperature before VD is 1680-1685 ℃, the argon pressure is controlled to be 0.1-0.3 MPa before a vacuum pump is started, the slag surface micro-motion molten steel is not exposed, the timing is started when the vacuum degree reaches 100-110 Pa, the holding time is 20-25 min, the vacuum breaking temperature is 1615-1620 ℃, alloy is added according to the molten steel component reference target component, the argon pressure is adjusted to be 0.3-0.5 MPa, the static argon blowing time is 30-35 min, after the static argon blowing is finished, phi 10mm silicon-calcium cored wire 2.2-2.3 m/t steel is added, the hanging package temperature is 1600-1610 ℃, and the carbonized rice husk is 1.7-1.8 kg/t steel;
the die casting is as follows: pouring a steel ingot of 0.6-8.4t, after molten steel is poured onto a cap opening for 20-30 mm, starting gradual flow reduction to perform slow pouring, after pouring the molten steel onto one half of the pouring height of the cap opening, closing a sliding plate to stop pouring for 6-8S, and then performing rapid flow opening and pouring for a plurality of times, wherein the interval time is 4-5S each time, until the pouring height and the filling time are reached, and adding the heat insulating agent coke powder of the cap opening when the molten steel is poured onto the cap opening for 2/3 of the height.
4. A method according to claim 3, wherein in the die casting step, 2 ingot plates are cast, each plate having 6 pieces of 3.16t ingot; the casting time of single-disc die casting is strictly controlled, the spindle body is 6-6.5 min, and the cap opening is 6-6.5 min.
5. A method of manufacture according to claim 3, wherein the heating process is: when the soaking pit is arranged, the ingot temperature is 600-850 ℃, the preheating section of the soaking pit is required, the heating time is more than or equal to 1h, and the temperature is increased to 950-960 ℃; the heating section is heated to 1200-1220 ℃ with the temperature rising speed less than or equal to 180/h, the temperature rising time more than or equal to 2.5h, the temperature rising is carried out to 1200-1220 ℃ with the temperature equalizing time of 1.5-2 h;
the high-pressure water descaling is as follows: the dephosphorization water adopts turbid circulating water, and the water spraying pressure is 20-30MPa.
6. A method of manufacture as claimed in claim 3 wherein the steel is produced in a gauge of Φ50-200mm.
7. A method of manufacture according to claim 3, wherein the rolling process is:
BD cogging process: cogging by adopting a BD blooming mill, rolling for 11 times, and reducing: 80 to 80.5mm of the 1 st pass, 80 to 80.5mm of the 2 nd pass, 95 to 95.5mm of the 3 rd pass, 85 to 85.5mm of the 4 th pass, 72 to 72.5mm of the 5 th pass, 82 to 82.5mm of the 6 th pass, 69 to 69.5mm of the 7 th pass, 75 to 75.5mm of the 8 th pass, 32 to 32.5mm of the 9 th pass, 20 to 20.5mm of the 10 th pass, 32 to 32.5mm of the 11 th pass, and then bar materials are discharged through a 3-frame 850mm rolling mill and enter a continuous rolling unit.
8. The production method according to claim 3 or 7, wherein the initial rolling temperature of the steel material is 1100 ℃ to 1130 ℃; finish rolling temperature is 950 ℃ to 1100 ℃; the finishing temperature is 850-920 ℃.
9. The method according to claim 3, wherein the heat preservation process is as follows: the temperature of the lower heat preservation pit is more than or equal to 600 ℃, the heat preservation is carried out for 48-60h, and the temperature of the pit outlet is less than or equal to 130 ℃.
10. The method of producing according to claim 9, wherein the heat-preserved steel material is subjected to a heat treatment comprising the steps of:
1) Quenching: preserving heat for 50-70min at 930-950 ℃ and cooling with oil;
2) Tempering: heat preservation is carried out for 110-130min at 635-645 ℃ and water cooling is carried out.
CN202310795397.7A 2023-06-30 2023-06-30 Production and preparation method of high-aluminum plastic die steel Pending CN116790993A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202310795397.7A CN116790993A (en) 2023-06-30 2023-06-30 Production and preparation method of high-aluminum plastic die steel

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202310795397.7A CN116790993A (en) 2023-06-30 2023-06-30 Production and preparation method of high-aluminum plastic die steel

Publications (1)

Publication Number Publication Date
CN116790993A true CN116790993A (en) 2023-09-22

Family

ID=88049466

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202310795397.7A Pending CN116790993A (en) 2023-06-30 2023-06-30 Production and preparation method of high-aluminum plastic die steel

Country Status (1)

Country Link
CN (1) CN116790993A (en)

Similar Documents

Publication Publication Date Title
CN105177215B (en) Efficient production process of high aluminum-alloy-content structure round steel
EP3050994A1 (en) Non-quenched and tempered steel and manufacturing method therefor
CN114250402B (en) Manufacturing method of low-carbon nitrogen-containing austenitic stainless steel bar
EP3050995A1 (en) Non-quenched and tempered steel and manufacturing method therefor
CN109207856B (en) Nitrogenous plastic die flat steel and production method thereof
CN114393181B (en) Assembled frog and preparation method thereof
CN108893682B (en) Die steel billet and preparation method thereof
EP3050991A1 (en) Non-quenched and tempered steel and manufacturing method therefor
CN103045948A (en) High-chromium steel and manufacturing method thereof
AU2022215193A1 (en) Method for producing hypereutectoid steel rail resistant to contact fatigue
CN114892094B (en) Pre-hardened mirror plastic die steel and production method thereof
CN113145807A (en) Rare earth bearing steel ingot for shield machine and production method thereof
CN111041352B (en) External refining production method of wire rod for cutting diamond wire
CN115261564B (en) Pure iron as non-aluminum deoxidizing material for amorphous soft magnetic thin belt and preparation method thereof
CN114875334B (en) Pre-hardened mirror plastic die steel and smelting method thereof
CN114150219B (en) Steel for large-specification high-strength mining machinery drill bit and production process
CN116790993A (en) Production and preparation method of high-aluminum plastic die steel
CN110343811B (en) Smelting and forging method of high-toughness alloy steel forging
CN112281055A (en) Low-carbon steel plate with excellent low-temperature impact toughness performance and production method thereof
CN116815058A (en) Production and preparation method of steel for camshaft
CN115094321B (en) Steel for long-service-life injection molding machine screw and preparation method thereof
CN115927795B (en) Ultrahigh Al for producing bearing steel2O3Refining slag system and preparation process thereof
CN115584435B (en) High-strength steel for cold extrusion molding of heavy cross shaft and preparation method thereof
CN112126743B (en) Production method of low-aluminum-content Cr5 steel ingot for supporting roll
CN115505853A (en) Square steel for high-speed rail brake and preparation method thereof

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