CN115323288B - Preparation method of chalcogenide free-cutting hot-work die steel CX2344 - Google Patents

Preparation method of chalcogenide free-cutting hot-work die steel CX2344 Download PDF

Info

Publication number
CN115323288B
CN115323288B CN202210957357.3A CN202210957357A CN115323288B CN 115323288 B CN115323288 B CN 115323288B CN 202210957357 A CN202210957357 A CN 202210957357A CN 115323288 B CN115323288 B CN 115323288B
Authority
CN
China
Prior art keywords
equal
less
furnace
forging
temperature
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.)
Active
Application number
CN202210957357.3A
Other languages
Chinese (zh)
Other versions
CN115323288A (en
Inventor
张涛
敬小龙
王绍华
杨清明
张帅军
廖明航
杜科
王超
邓吉宁
莫敦
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.)
Jiangyou Changxiang Special Steel Manufacturing Co ltd
Original Assignee
Jiangyou Changxiang Special Steel Manufacturing 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 Jiangyou Changxiang Special Steel Manufacturing Co ltd filed Critical Jiangyou Changxiang Special Steel Manufacturing Co ltd
Priority to CN202210957357.3A priority Critical patent/CN115323288B/en
Publication of CN115323288A publication Critical patent/CN115323288A/en
Application granted granted Critical
Publication of CN115323288B publication Critical patent/CN115323288B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

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
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/24—Ferrous alloys, e.g. steel alloys containing chromium with vanadium
    • 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
    • C21C5/527—Charging of the electric furnace
    • 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
    • C21C7/076—Use of slags or fluxes as treating agents
    • 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
    • C21D1/26—Methods of annealing
    • 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
    • C21D8/005—Modifying the physical properties by deformation combined with, or followed by, heat treatment 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
    • 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
    • C22C38/001—Ferrous alloys, e.g. steel alloys containing N
    • 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
    • C22C38/06—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
    • C22C38/22—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
    • C22C38/44—Ferrous alloys, e.g. steel alloys containing chromium with nickel 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
    • C22C38/46—Ferrous alloys, e.g. steel alloys containing chromium with nickel with vanadium
    • 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
    • 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

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)
  • Forging (AREA)
  • Heat Treatment Of Steel (AREA)

Abstract

The invention provides a preparation method of sulfur free-cutting hot work die steel CX2344. The composite material comprises the following chemical components in percentage by weight: 0.36 to 0.42 percent of C, 0.80 to 1.20 percent of Si, 0.30 to 0.60 percent of Mn, 0.08 to 0.13 percent of S, less than or equal to 0.020 percent of P, 4.70 to 5.50 percent of Cr, less than or equal to 0.30 percent of Ni, 0.80 to 1.20 percent of V, 1.45 to 1.75 percent of Mo, 0.015 to 0.035 percent of Al, less than or equal to 0.0004 percent of H, less than or equal to 0.0030 percent of O, less than or equal to 0.0200 percent of N, and the balance of Fe; during the preparation, the red-fed steel ingot is subjected to forging treatment, and the forging temperature is more than or equal to 900 ℃; and (5) utilizing the waste heat after forging to enter an annealing furnace for heat treatment. The die steel of the invention does not crack in the forging process, and meets the NADCA#207-2003 standard requirement after superfine grain treatment.

Description

Preparation method of chalcogenide free-cutting hot-work die steel CX2344
Technical Field
The invention relates to the technical field of alloy steel manufacturing, in particular to a preparation method of sulfur free-cutting hot work die steel CX2344.
Background
Hot work die steel refers to alloy tool steel suitable for making dies for hot deforming metals, such as hot forging dies, hot extrusion dies, die casting dies, hot forging dies, and the like. Since the hot-working mold is operated under high temperature and high pressure conditions for a long time, the mold material is required to have high strength, hardness and thermal stability, and in particular, should have high heat resistance, thermal fatigue, toughness and wear resistance.
The die steel CX2344 is hot work die steel, the hot work die is generally used in a state of higher hardness, and is subjected to great impact force during working, the die cavity is contacted with high-temperature metal, and the die cavity is repeatedly heated and cooled, so that the use condition is extremely bad; and the hot working die steel CX2344 has high hardness, increased finish machining difficulty and difficult guarantee of precision.
In order to improve the service life of the hot working die, the problems of high processing difficulty and difficult guarantee of precision are solved, and meanwhile, in order to improve the production efficiency of cutting processing, the free-cutting die casting die steel of +S is developed.
The existing manufacturing process of hot work die steel generally comprises a smelting process, a heat treatment process, a forging process, a heat treatment process, a machining process and a heat treatment process; in order to make the crystal grains more uniform, in the manufacturing process, the steel ingot formed after smelting and casting needs to be cooled to the room temperature and then enters an annealing process, the steel ingot cooled to the room temperature after the annealing process is finished enters a forging process, namely, the steel ingot is reheated from the room temperature to the annealing temperature and the steel ingot is reheated from the room temperature to the forging temperature, namely, the steel ingot is forged from the low temperature to the high temperature, and the process is favorable for the diffusion of atoms and can make the crystal grains more uniform. However, if the S-series free-cutting hot-work die steel (including die casting die) is forged from low temperature to high temperature, a melting phenomenon occurs in a forging temperature range, because a large amount of S element is added, so that the high-temperature plasticity of the forging temperature range is poor, cracking is easy to occur during forging, and how to solve the problem that the steel ingot is cracked in the forging temperature range due to the vulcanization is the important point of the invention.
The applicant found that the prior art has at least the following technical problems:
in the prior art, S is added into the free-cutting die casting die steel, and because of the large addition of S element, the high-temperature plasticity of a forging temperature interval is poor, and cracking is easy to occur during forging.
Disclosure of Invention
The invention aims to provide a preparation method of sulfur free-cutting hot-working die steel CX2344, which aims to solve the technical problems that S free-cutting die steel in the prior art is poor in high-temperature plasticity in a forging temperature range and easy to crack during forging due to the fact that a large amount of S element is added. The preferred technical solutions of the technical solutions provided by the present invention can produce a plurality of technical effects described below.
In order to achieve the above purpose, the present invention provides the following technical solutions:
the invention provides a preparation method of sulfur free-cutting hot work die steel CX2344, which is characterized by comprising the following steps: the sulfur free cutting hot work die steel CX2344 comprises the following chemical components in percentage by weight:
0.36-0.42% of C, 0.80-1.20% of Si, 0.30-0.60% of Mn, 0.08-0.13% of S, less than or equal to 0.020% of P, 4.70-5.50% of Cr, less than or equal to 0.30% of Ni, 0.80-1.20% of V, 1.45-1.75% of Mo, 0.015-0.035% of Al, less than or equal to 0.0004% of H, less than or equal to 0.0030% of O, less than or equal to 0.0200% of N, and the balance of Fe;
the preparation of the chalcogenide free-cutting hot-work die steel CX2344 comprises a smelting process, a forging process and a heat treatment process; after the smelting and casting steel ingot is solidified, carrying out forging treatment on the red-cast steel ingot when the temperature of the steel ingot is less than or equal to 1300 ℃, and keeping the forging temperature at more than or equal to 900 ℃; and after the forging process is finished, utilizing the waste heat after forging of the forging piece to enter an annealing furnace to enter a heat treatment process.
Further, when forging treatment is performed, the forging temperature is 1260-950 ℃.
Further, the weight percentages of the chemical components are as follows: 0.38% -0.40% of C, 0.90% -1.10% of Si, 0.40% -0.50% of Mn, 0.10% -0.12% of S, less than or equal to 0.020% of P, 5.00% -5.20% of Cr, less than or equal to 0.30% of Ni, 0.90% -1.10% of V, 1.55% -1.65% of Mo, 0.020% -0.030% of Al, less than or equal to 0.0004% of H, less than or equal to 0.0030% of O, less than or equal to 0.0200% of N and the balance of Fe.
Further, the weight percentages of the chemical components are as follows: 0.39% of C, 1.00% of Si, 0.45% of Mn, 0.11% of S, less than or equal to 0.020% of P, 5.10% of Cr, less than or equal to 0.30% of Ni, 1.00% of V, 1.60% of Mo, 0.025% of Al, less than or equal to 0.0004% of H, less than or equal to 0.0030% of O, less than or equal to 0.0200% of N, and the balance of Fe.
Further, the preparation of the sulfur-based free-cutting hot work die steel CX2344 specifically comprises the following steps:
s1, smelting
S11, proportioning the raw materials according to the chemical components, and baking the ferroalloy in the raw materials at a high temperature;
s12, entering an electric furnace, cleaning a steel ladle before smelting, and baking well, wherein before raw materials in the electric furnace are filled, soot blowing is needed, and carburetion is prevented; 15-17Kg/T of stone dust is added according to the total steelmaking amount at present, then the raw materials prepared in the step S11 are added for melting, a slag former is added for slag formation in the melting process, the molten steel is prevented from being exposed, and the addition amount of the slag former is 1.5-2.0Kg/T according to the total steelmaking amount at present; and using calcium wires for diffusion deoxidation, wherein the adding amount of the calcium wires is 4.8-5.2m/T according to the total steelmaking amount; when the smelting temperature is more than or equal to 1620 ℃, the double pipes are lifted and blown, the wild air valve is opened to perform water pumping and cooling on the cable and the furnace cover lifting cylinder, and the carbon content of the terminal point is controlled to be 0.18%; then entering a reduction period, wherein the reduction method adopted in the reduction period is as follows: adding baked lime 18-22Kg/T and deoxidizer 2-4Kg/T according to the total steelmaking amount, pre-reducing, adding deoxidizer from a furnace door after slagging, blowing argon into the furnace door, stirring for more than or equal to 10min, and thoroughly reducing; regulating Si content to 0.95% before tapping, and tapping to remove slag;
s13, entering an LF furnace, adding 18-22Kg/T of baked lime, 5.5-6.5Kg/T of cap slag and 1.5-2.5Kg/T of fire brick and 2.5Kg/T of deoxidizer into the LF furnace according to the total steelmaking amount, and making white slag, controlling the refining time of the white slag to be more than or equal to 30min, and continuously adding the deoxidizer in the process of maintaining the refining of the white slag so as to maintain a strong reducing atmosphere; sampling when the chemical clearing temperature is more than or equal to 1560 ℃, and adjusting the chemical components according to the content requirements of the chemical components; after the adjustment is completed for at least 10min, deslagging and vacuumizing are carried out; sampling again, adjusting chemical composition control: 0.42% of C, 0.90% of Si, 0.45% of Mn, 4.90% of Cr, 1.44% of Mo, 0.83% of V and 0.095% of S; after chemical components are regulated, when the temperature reaches 1700 ℃, feeding Al wires until the Al content is 0.11%, adding fire bricks, thoroughly breaking slag, and adding sulfur core wires until the S content is 0.095%;
s14, entering a VD furnace, and controlling the ultimate vacuum pressure to be less than or equal to 67Pa and the time to be more than or equal to 12min; the temperature of the hanging bag is 1550-1555 ℃;
s15, pouring, namely cleaning an ingot mould, ensuring that a pouring system is clean and dry, and filling argon into a pouring tube and the mould for 3 minutes before pouring, wherein the amount of casting powder is 2 kg/branch; when in pouring, the ladle hanging temperature is 1550-1555 ℃; controlling the injection temperature and the injection speed, controlling the injection temperature to 1550-1555 ℃, and uniformly feeding 0.3-0.5Kg/T of lanthanum-cerium mixed rare earth metal during casting;
s2, forging
S21, a first sequence: when the temperature of the steel ingot is less than or equal to 1300 ℃, red-feeding the steel ingot to a gas heating furnace section, heating to 1190-1210 ℃, preserving heat for 2.5-3 minutes according to the thickness of the steel ingot per millimeter, and after the heat preservation is finished, carrying out first order, namely pressing the clamp to ensure that phi 400mmX is 650mm, staggering water purifying ports, drawing out and rounding to the same size at the two ends, wherein the forging deformation is less than or equal to 10%, so that the surface of the steel ingot forms compressive stress; heating to 1190-1210 ℃ in a furnace, and preserving heat for 1.5-2 minutes per millimeter according to the thickness of the steel ingot;
s22, upsetting to the height H=950 mm, drawing out 820mm again, chamfering, returning to the furnace, heating to 1190-1210 ℃, and preserving heat for 1.5-2 minutes per millimeter according to the thickness of the steel ingot;
s23, upsetting to the height H=950 mm, flattening 700mm, turning over 90 degrees, pressing 820mm again, chamfering, returning to the furnace, heating to 1190-1210 ℃, and preserving heat for 1.5-2 minutes per millimeter according to the thickness of the steel ingot;
s24, fourth procedure: upsetting to a height H=950 mm, flattening 700mm, turning over 90 degrees, pressing 820mm again, chamfering, returning to the furnace, heating to 1190-1210 ℃, and preserving heat for 1.5-2 minutes per millimeter according to the thickness of the steel ingot;
s25, a fifth procedure: upsetting to a height H=800 mm, drawing and trimming all parts to a ruler, and completing forging to obtain a forging piece;
s3, heat treatment
After forging, utilizing the waste heat of the forged piece after forging to enter an annealing furnace for annealing, wherein the annealing temperature is 850-870 ℃, and the heat preservation time is 2.5-3.5 minutes according to the thickness of the forged piece per millimeter; air cooling is carried out after heat preservation is finished, and an annealed forging piece is obtained;
s4, machining
Machining according to the machining size reserved allowance to obtain a machined die steel plate;
s5, ultra-fine grain treatment
Quenching: heating to 1030 ℃ for 1-2 minutes according to the effective thickness of the plate material per millimeter, quenching into oil, discharging oil at 150-170 ℃, loading into a tempering furnace, tempering at 730-750 ℃ for 2.5-3.0 minutes according to the effective thickness of the plate material per millimeter, discharging from the furnace for air cooling, and obtaining the chalcogenide free-cutting hot work die steel CX2344 after the air cooling is finished.
Further, in the step S11, the iron alloy is baked at a high temperature by heating the iron alloy to 730-780 ℃ in a baking furnace, and maintaining the temperature at 730-780 ℃ for at least 6 hours.
Further, in the step S12, the slag former is a mixture of calcium oxide and aluminum oxide, and the mass ratio of the calcium oxide to the aluminum oxide is 3.5-4.5:1.
Further, in the step S12, the deoxidizer added during the pre-reduction is fe—si powder.
Further, in the step S13, the deoxidizer is fe—si powder.
Based on the technical scheme, the embodiment of the invention at least has the following technical effects:
(1) According to the preparation method of the sulfur free-cutting hot-work die steel CX2344, the Mn content is improved to 0.3% -0.6%, feS+Mn- & gtMnS+Fe occurs during smelting, moderately improved Mn content forms high-melting-point MnS which exists in a crystal in a spherical shape and a granular shape, the formation of eutectic formation or excessive content of low-melting-point FeS and Fe is prevented, and further the high-temperature plasticity reduction of a forging temperature interval caused by the formation of the eutectic of excessive FeS and Fe is avoided, and the cracking condition in the forging process is avoided.
(2) According to the preparation method of the chalcogenide free-cutting hot-work die steel CX2344, the Mo content is improved to 1.45% -1.75%, at high temperature, mo atoms replace part of Fe atoms, and because the size of the radius of the Mo atoms is larger than that of the radius of the Fe atoms, gaps among the atoms are reduced, a certain strengthening effect is achieved, a replacement solid solution is formed, and the purpose of replacement strengthening of the hot-work die steel is achieved.
(3) According to the preparation method of the chalcogenide free-cutting hot-work die steel CX2344, after smelting, the steel ingot is red and sent to a forging process, so that the formation of eutectic of FeS and Fe or excessive content can be avoided, the influence of vulcanization on the high-temperature plasticity deterioration of a forging temperature interval can be avoided, and the cracking condition in the forging process can be avoided; and, after the forging is finished, heat treatment is carried out, and the crystal grains are subjected to homogenization treatment, so that the obtained sulfur free-cutting hot work die steel CX2344 meets various performance requirements of the sulfur free-cutting hot work die steel CX2344.
(4) According to the preparation method of the chalcogenide free-cutting hot-work die steel CX2344, the lanthanum-cerium mixed rare earth metal is fed during casting, the addition amount of the lanthanum-cerium mixed rare earth metal is less than or equal to 0.10 percent according to the total steelmaking amount, the deoxidization is more thorough, and the spheroidization of sulfides is facilitated.
Drawings
In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 shows the result of detecting nonmetallic inclusion of die steel CX2344 obtained in example 1 at a multiple of 100 times;
FIG. 2 shows the result of detecting nonmetallic inclusion of die steel CX2344 obtained in example 2 at a magnification of 100 times;
FIG. 3 shows the result of detecting nonmetallic inclusion of die steel CX2344 obtained in example 3 at a magnification of 100 times;
FIG. 4 shows the result of metallographic examination of die steel CX2344 obtained in example 1 at a magnification of 500 times;
FIG. 5 shows the result of metallographic examination of die steel CX2344 obtained in example 2 at a magnification of 500 times;
FIG. 6 shows the result of metallographic examination of die steel CX2344 obtained in example 3 at a magnification of 500 times.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. It will be apparent that the described embodiments are only some, but not all, embodiments of the invention. All other embodiments, based on the examples herein, which are within the scope of the invention as defined by the claims, will be within the scope of the invention as defined by the claims.
Material description:
the lanthanum cerium mischmetal in the examples described below was purchased from the company of liability for rare earth thinning, silver, pennsylvania.
1. Preparation examples:
example 1:
1.1 chemical composition (weight percent):
0.39% of C, 1.00% of Si, 0.45% of Mn, 0.11% of S, less than or equal to 0.020% of P, 5.10% of Cr, less than or equal to 0.30% of Ni, 1.00% of V, 1.60% of Mo, 0.025% of Al, less than or equal to 0.0004% of H, less than or equal to 0.0030% of O, less than or equal to 0.0200% of N, and the balance of Fe.
1.2, the preparation method specifically comprises the following steps:
s1, smelting
S11, proportioning the raw materials according to the chemical components, and baking the ferroalloy in the raw materials at a high temperature; the high-temperature baking of the ferroalloy is to put the ferroalloy into a baking furnace to be heated to 750 ℃ and keep the temperature at 750 ℃ for 6 hours;
s12, entering an electric furnace, cleaning a steel ladle before smelting, and baking well, wherein before raw materials in the electric furnace are filled, soot blowing is needed, and carburetion is prevented; according to the total steelmaking amount, 16Kg/T of the lime stone is added, the raw materials prepared in the step S11 are added for melting, a slag former is added for slag formation in the melting process, molten steel exposure is avoided, the addition amount of the slag former is added according to the total steelmaking amount at the time by 1.8Kg/T, the slag former is a mixture of calcium oxide and aluminum oxide, and the mass ratio of the calcium oxide to the aluminum oxide is 4:1; and using calcium wires for diffusion deoxidation, wherein the adding amount of the calcium wires is 5m/T according to the total steelmaking amount at present; when the smelting temperature is more than or equal to 1620 ℃, the double pipes are lifted and blown, the wild air valve is opened to perform water pumping and cooling on the cable and the furnace cover lifting cylinder, and the carbon content of the terminal point is controlled to be 0.18%; then entering a reduction period, wherein the reduction method adopted in the reduction period is as follows: adding baked lime 20Kg/T and deoxidizer (Fe-Si powder) 3Kg/T according to the total steelmaking amount, pre-reducing, wherein the deoxidizer is added from a furnace door after slag formation, and argon is blown in and stirred for more than or equal to 10min to thoroughly reduce; regulating Si content to 0.95% before tapping, and tapping to remove slag;
s13, entering an LF furnace, adding baked lime 18-22Kg/T, cap slag 6Kg/T, fire brick 2Kg/T and deoxidizer (Fe-Si powder) 2.5Kg/T into the LF furnace according to the total steelmaking amount, making white slag, controlling the refining time of the white slag to be more than or equal to 30min, and continuously adding deoxidizer (Fe-Si powder) in the process of maintaining the refining of the white slag so as to maintain a strong reducing atmosphere; sampling when the chemical clearing temperature is more than or equal to 1560 ℃, and adjusting the chemical components according to the content requirements of the chemical components; after the adjustment is completed for at least 10min, deslagging and vacuumizing are carried out; sampling again, adjusting chemical composition control: 0.42% of C, 0.90% of Si, 0.45% of Mn, 4.90% of Cr, 1.44% of Mo, 0.83% of V and 0.095% of S; after chemical components are regulated, when the temperature reaches 1700 ℃, feeding Al wires until the Al content is 0.11%, adding fire bricks, thoroughly breaking slag, and adding sulfur core wires until the S content is 0.095%;
s14, entering a VD furnace, and controlling the ultimate vacuum pressure to be less than or equal to 67Pa and the time to be more than or equal to 12min; the temperature of the hanging bag is 1550-1555 ℃;
s15, pouring, namely cleaning an ingot mould, ensuring that a pouring system is clean and dry, and filling argon into a pouring tube and the mould for 3 minutes before pouring, wherein the amount of casting powder is 2 kg/branch; when in pouring, the ladle hanging temperature is 1550-1555 ℃; controlling the injection temperature and the injection speed, controlling the injection temperature to 1550-1555 ℃, and uniformly feeding 0.4Kg/T of lanthanum-cerium mixed rare earth metal during casting;
s2, forging
S21, a first sequence: when the temperature of the steel ingot is less than or equal to 1300 ℃, red-feeding the steel ingot to a gas heating furnace section, heating to 1200 ℃, preserving heat for 2.8 minutes according to the thickness of the steel ingot per millimeter, and after the heat preservation is finished, carrying out first order, namely pressing clamp to ensure that phi 400mmX650mm is arranged, forming water purifying ports in a staggered way, drawing out and rounding to the same size at the two ends, wherein the forging deformation is less than or equal to 10%, so that the surface of the steel ingot forms compressive stress; heating to 1200 ℃ in a furnace, and preserving heat for 1.8 minutes according to the thickness of the steel ingot per millimeter;
s22, upsetting to the height H=950 mm, drawing out 820mm, chamfering, returning to the furnace, heating to 1200 ℃, and preserving heat for 1.8 minutes according to the thickness of the steel ingot per millimeter;
s23, upsetting to the height H=950 mm, flattening 700mm, turning over 90 degrees, pressing 820mm again, chamfering, returning to the furnace, heating to 1200 ℃, and preserving heat for 1.8 minutes per millimeter according to the thickness of the steel ingot;
s24, fourth procedure: upsetting to a height H=950 mm, flattening 700mm, turning over 90 degrees, pressing 820mm again, chamfering, returning to the furnace, heating to 1200 ℃, and preserving heat for 1.8 minutes per millimeter according to the thickness of the steel ingot;
s25, a fifth procedure: upsetting to a height H=800 mm, drawing and trimming all parts to a ruler, and completing forging to obtain a forging piece;
s3, heat treatment
After forging, utilizing the waste heat of the forged piece after forging to enter an annealing furnace for annealing, wherein the annealing temperature is 860 ℃, and the heat preservation time is 3 minutes according to the thickness of the forged piece per millimeter; air cooling is carried out after heat preservation is finished, and an annealed forging piece is obtained;
s4, machining
Machining according to the machining size reserved allowance to obtain a machined die steel plate;
s5, ultra-fine grain treatment
Quenching: heating to 1030 ℃, preserving heat for 1.5 minutes per millimeter according to the effective thickness of the plate, quenching into oil, discharging oil at 160 ℃, loading into a tempering furnace, tempering, preserving heat for 2.8 minutes per millimeter according to the effective thickness of the plate at 740 ℃, discharging from the furnace for air cooling, and obtaining the chalcogenide free-cutting hot work die steel CX2344 after the air cooling is finished.
Example 2:
2.1 chemical composition (weight percent):
0.40% of C, 0.90% of Si, 0.50% of Mn, 0.12% of S, less than or equal to 0.020% of P, 5.20% of Cr, less than or equal to 0.30% of Ni, 0.90% of V, 1.65% of Mo, 0.020% of Al, less than or equal to 0.0004% of H, less than or equal to 0.0030% of O, less than or equal to 0.0200% of N, and the balance of Fe.
2.2, the preparation method specifically comprises the following steps:
s1, smelting
S11, proportioning the raw materials according to the chemical components, and baking the ferroalloy in the raw materials at a high temperature; the high-temperature baking of the ferroalloy is to put the ferroalloy into a baking furnace to be heated to 780 ℃ and keep the temperature at 780 ℃ for 6 hours;
s12, entering an electric furnace, cleaning a steel ladle before smelting, and baking well, wherein before raw materials in the electric furnace are filled, soot blowing is needed, and carburetion is prevented; according to the total steelmaking amount at present, 17Kg/T of lime stone is added, then the raw materials prepared in the step S11 are added for melting, a slag former is added for slag formation in the melting process, molten steel exposure is avoided, the addition amount of the slag former is added according to the total steelmaking amount at present at 2.0Kg/T, the slag former is a mixture of calcium oxide and aluminum oxide, and the mass ratio of the calcium oxide to the aluminum oxide is 4.5:1; and using calcium wires for diffusion deoxidation, wherein the adding amount of the calcium wires is 4.8m/T according to the total steelmaking amount; when the smelting temperature is more than or equal to 1620 ℃, the double pipes are lifted and blown, the wild air valve is opened to perform water pumping and cooling on the cable and the furnace cover lifting cylinder, and the carbon content of the terminal point is controlled to be 0.18%; then entering a reduction period, wherein the reduction method adopted in the reduction period is as follows: adding baked lime 18Kg/T and deoxidizer (Fe-Si powder) 4Kg/T according to the total steelmaking amount, pre-reducing, wherein the deoxidizer is added from a furnace door after slag formation, blowing argon into the furnace door, stirring for more than or equal to 10min, and thoroughly reducing; regulating Si content to 0.95% before tapping, and tapping to remove slag;
s13, entering an LF furnace, adding 22Kg/T of baked lime, 5.5Kg/T of cap slag, 2.5Kg/T of fire brick and 2Kg/T of deoxidizer (Fe-Si powder) into the LF furnace according to the total steelmaking amount, and making white slag, controlling the refining time of the white slag to be more than or equal to 30min, and continuously adding the deoxidizer (Fe-Si powder) in the process of maintaining the refining of the white slag so as to maintain a strong reducing atmosphere; sampling when the chemical clearing temperature is more than or equal to 1560 ℃, and adjusting the chemical components according to the content requirements of the chemical components; after the adjustment is completed for at least 10min, deslagging and vacuumizing are carried out; sampling again, adjusting chemical composition control: 0.42% of C, 0.90% of Si, 0.45% of Mn, 4.90% of Cr, 1.44% of Mo, 0.83% of V and 0.095% of S; after chemical components are regulated, when the temperature reaches 1700 ℃, feeding Al wires until the Al content is 0.11%, adding fire bricks, thoroughly breaking slag, and adding sulfur core wires until the S content is 0.095%;
s14, entering a VD furnace, and controlling the ultimate vacuum pressure to be less than or equal to 67Pa and the time to be more than or equal to 12min; the temperature of the hanging bag is 1550-1555 ℃;
s15, pouring, namely cleaning an ingot mould, ensuring that a pouring system is clean and dry, and filling argon into a pouring tube and the mould for 3 minutes before pouring, wherein the amount of casting powder is 2 kg/branch; when in pouring, the ladle hanging temperature is 1550-1555 ℃; controlling the injection temperature and the injection speed, controlling the injection temperature to 1550-1555 ℃, and uniformly feeding 0.3Kg/T of lanthanum-cerium mixed rare earth metal during casting;
s2, forging
S21, a first sequence: when the temperature of the steel ingot is less than or equal to 1300 ℃, red-feeding the steel ingot to a gas heating furnace section, heating to 1190 ℃, preserving heat for 3 minutes according to the thickness of the steel ingot per millimeter, pressing a clamp to ensure phi 400mmX650mm after the heat preservation is finished, staggering water purifying ports, drawing out and rounding to the same size at two ends, and forging the deformation amount to be less than or equal to 10 percent, so that the surface of the steel ingot forms compressive stress; heating to 1190-1210 ℃ in a furnace, and preserving heat for 2 minutes according to the thickness of the steel ingot per millimeter;
s22, upsetting to the height H=950 mm, drawing out 820mm, chamfering, returning to the furnace, heating to 1190 ℃, and preserving heat for 2 minutes according to the thickness of the steel ingot per millimeter;
s23, upsetting to the height H=950 mm, flattening 700mm, turning over 90 degrees, pressing 820mm again, chamfering, returning to the furnace, heating to 1190 ℃, and preserving heat for 2 minutes per millimeter according to the thickness of the steel ingot;
s24, fourth procedure: upsetting to a height H=950 mm, flattening 700mm, turning over 90 degrees, pressing 820mm again, chamfering, returning to the furnace, heating to 1190 ℃, and preserving heat for 2 minutes per millimeter according to the thickness of the steel ingot;
s25, a fifth procedure: upsetting to a height H=800 mm, drawing and trimming all parts to a ruler, and completing forging to obtain a forging piece;
s3, heat treatment
After forging, utilizing the waste heat after forging of the forging piece to enter an annealing furnace for annealing, wherein the annealing temperature is 850 ℃, and the heat preservation time is 3.5 minutes according to the thickness of the forging piece per millimeter; air cooling is carried out after heat preservation is finished, and an annealed forging piece is obtained;
s4, machining
Machining according to the machining size reserved allowance to obtain a machined die steel plate;
s5, ultra-fine grain treatment
Quenching: heating to 1030 ℃ for 2 minutes at the effective thickness of the plate material per millimeter, quenching into oil, discharging the oil at 150 ℃, loading into a tempering furnace, tempering, wherein the tempering temperature is 730 ℃, the heat preservation time is 3.0 minutes at the effective thickness of the plate material per millimeter, discharging from the furnace for air cooling, and obtaining the chalcogenide free cutting hot work die steel CX2344 after the air cooling is finished.
Example 3:
3.1 chemical composition (weight percent):
0.38% of C, 1.10% of Si, 0.40% of Mn, 0.10% of S, less than or equal to 0.020% of P, 5.00% of Cr, less than or equal to 0.30% of Ni, 1.10% of V, 1.55% of Mo, 0.030% of Al, less than or equal to 0.0004% of H, less than or equal to 0.0030% of O, less than or equal to 0.0200% of N, and the balance of Fe.
2.2, the preparation method specifically comprises the following steps:
s1, smelting
S11, proportioning the raw materials according to the chemical components, and baking the ferroalloy in the raw materials at a high temperature; the ferroalloy is baked at high temperature, namely the ferroalloy is put into a baking furnace to be heated to 730 ℃ and is kept at the temperature of 730 ℃ for at least 8 hours;
s12, entering an electric furnace, cleaning a steel ladle before smelting, and baking well, wherein before raw materials in the electric furnace are filled, soot blowing is needed, and carburetion is prevented; according to the total steelmaking amount at present, 15Kg/T of lime stone is added, then the raw materials prepared in the step S11 are added for melting, a slag former is added for slag formation in the melting process, molten steel exposure is avoided, the addition amount of the slag former is added according to the total steelmaking amount at present at 1.5Kg/T, the slag former is a mixture of calcium oxide and aluminum oxide, and the mass ratio of the calcium oxide to the aluminum oxide is 3.5:1; and using calcium wires for diffusion deoxidation, wherein the adding amount of the calcium wires is 5.2m/T according to the total steelmaking amount at present; when the smelting temperature is more than or equal to 1620 ℃, the double pipes are lifted and blown, the wild air valve is opened to perform water pumping and cooling on the cable and the furnace cover lifting cylinder, and the carbon content of the terminal point is controlled to be 0.18%; then entering a reduction period, wherein the reduction method adopted in the reduction period is as follows: adding 22Kg/T of baked lime and 2Kg/T of deoxidizer (Fe-Si powder) according to the total steelmaking amount, pre-reducing, wherein the deoxidizer is added from a furnace door after slag formation, and argon is blown in and stirred for more than or equal to 10min to thoroughly reduce; regulating Si content to 0.95% before tapping, and tapping to remove slag;
s13, entering an LF furnace, adding 18Kg/T of baked lime, 6.5Kg/T of cap slag, 1.5Kg/T of fire brick and 3Kg/T of deoxidizer (Fe-Si powder) into the LF furnace according to the total steelmaking amount, and making white slag, controlling the refining time of the white slag to be more than or equal to 30min, and continuously adding the deoxidizer (Fe-Si powder) in the process of maintaining the refining of the white slag so as to maintain a strong reducing atmosphere; sampling when the chemical clearing temperature is more than or equal to 1560 ℃, and adjusting the chemical components according to the content requirements of the chemical components; after the adjustment is completed for at least 10min, deslagging and vacuumizing are carried out; sampling again, adjusting chemical composition control: 0.42% of C, 0.90% of Si, 0.45% of Mn, 4.90% of Cr, 1.44% of Mo, 0.83% of V and 0.095% of S; after chemical components are regulated, when the temperature reaches 1700 ℃, feeding Al wires until the Al content is 0.11%, adding fire bricks, thoroughly breaking slag, and adding sulfur core wires until the S content is 0.095%;
s14, entering a VD furnace, and controlling the ultimate vacuum pressure to be less than or equal to 67Pa and the time to be more than or equal to 12min; the temperature of the hanging bag is 1550-1555 ℃;
s15, pouring, namely cleaning an ingot mould, ensuring that a pouring system is clean and dry, and filling argon into a pouring tube and the mould for 3 minutes before pouring, wherein the amount of casting powder is 2 kg/branch; when in pouring, the ladle hanging temperature is 1550-1555 ℃; controlling the injection temperature and the injection speed, controlling the injection temperature to 1550-1555 ℃, and uniformly feeding 0.5Kg/T of lanthanum-cerium mixed rare earth metal during casting;
s2, forging
S21, a first sequence: when the temperature of the steel ingot is less than or equal to 1300 ℃, red-feeding the steel ingot to a gas heating furnace section, heating to 1210 ℃, preserving heat for 2.5 minutes according to the thickness of the steel ingot per millimeter, and after the heat preservation is finished, carrying out first order, namely pressing clamp to ensure that phi 400mmX650mm is arranged, forming water purifying ports in a staggered way, drawing out and rounding to the same size at the two ends, wherein the forging deformation is less than or equal to 10%, so that the surface of the steel ingot forms compressive stress; heating to 1210 ℃ in a furnace, and preserving heat for 1.5 minutes according to the thickness of the steel ingot per millimeter;
s22, upsetting to the height H=950 mm, drawing out 820mm, chamfering, returning to the furnace, heating to 1210 ℃, and preserving heat for 1.5 minutes according to the thickness of the steel ingot per millimeter;
s23, upsetting to the height H=950 mm, flattening 700mm, turning over 90 degrees, pressing 820mm again, chamfering, returning to the furnace, heating to 1210 ℃, and preserving heat for 1.5 minutes per millimeter according to the thickness of the steel ingot;
s24, fourth procedure: upsetting to a height H=950 mm, flattening 700mm, turning over 90 degrees, pressing 820mm again, chamfering, returning to the furnace, heating to 1210 ℃, and preserving heat for 1.5 minutes per millimeter according to the thickness of the steel ingot;
s25, a fifth procedure: upsetting to a height H=800 mm, drawing and trimming all parts to a ruler, and completing forging to obtain a forging piece;
s3, heat treatment
After forging, utilizing the waste heat after forging of the forging piece to enter an annealing furnace for annealing, wherein the annealing temperature is 870 ℃, and the heat preservation time is 2.5 minutes according to the thickness of the forging piece per millimeter; air cooling is carried out after heat preservation is finished, and an annealed forging piece is obtained;
s4, machining
Machining according to the machining size reserved allowance to obtain a machined die steel plate;
s5, ultra-fine grain treatment
Quenching: heating to 1030 ℃ for heat preservation for 1 minute per millimeter according to the effective thickness of the plate, quenching into oil, discharging oil at 170 ℃, loading into a tempering furnace, tempering, wherein the tempering temperature is 750 ℃, heat preservation for 2.5 minutes per millimeter according to the effective thickness of the plate, discharging from the furnace for air cooling, and obtaining the chalcogenide free cutting hot work die steel CX2344 after the air cooling is finished.
Example 4:
4.1 chemical composition (weight percent):
0.42% of C, 0.80% of Si, 0.60% of Mn, 0.13% of S, less than or equal to 0.020% of P, 4.70% of Cr, less than or equal to 0.30% of Ni, 1.20% of V, 1.75% of Mo, 0.015% of Al, less than or equal to 0.0004% of H, less than or equal to 0.0030% of O, less than or equal to 0.0200% of N, and the balance of Fe.
4.2 preparation method:
a sulfur-based free-cutting hot-work die steel CX2344 was obtained in the same manner as in example 1.
Example 5:
5.1 chemical composition (weight percent):
0.36% of C, 1.20% of Si, 0.30% of Mn, 0.08% of S, less than or equal to 0.020% of P, 5.50% of Cr, less than or equal to 0.30% of Ni, 0.80% of V, 1.75% of Mo, 0.035% of Al, less than or equal to 0.0004% of H, less than or equal to 0.0030% of O, less than or equal to 0.0200% of N, and the balance of Fe.
5.2 preparation method:
a sulfur-based free-cutting hot-work die steel CX2344 was obtained in the same manner as in example 1.
2. Experimental example:
the sulfur free-cutting hot-work die steels CX2344 obtained in examples 1 to 5 were each subjected to sampling test.
1. Chemical component detection
The test results are shown in table 1 below:
TABLE 1 chemical composition detection results (%)
Chemical composition Example 1 Example 2 Example 3 Example 4 Example 5
C 0.38 0.39 0.38 0.41 0.36
Si 0.94 0.91 1.08 0.81 1.16
Mn 0.45 0.48 0.42 0.58 0.32
S 0.112 0.118 0.095 0.0125 0.08
P 0.018 0.015 0.018 0.013 0.015
Cr 5.07 5.12 4.93 4.72 5.48
Ni 0.25 0.22 0.23 0.27 0.24
V 0.95 0.85 1.08 1.13 0.83
Mo 1.54 1.60 1.48 1.68 1.63
Al 0.024 0.020 0.023 0.016 0.033
H 0.0003 0.002 0.003 0.004 0.003
O 0.003 0.002 0.002 0.001 0.002
N 0.015 0.018 0.013 0.015 0.016
Fe Allowance of Allowance of Allowance of Allowance of Allowance of
2. Nonmetallic inclusion
2.1 detection of nonmetallic inclusions of various types (coarse and Fine System) according to the A method of ASTM E45-2018 Standard detection
2.2 results are shown in Table 2 below:
TABLE 2 detection results of nonmetallic inclusions
Figure BDA0003791900150000161
2.3 rating according to the NADCA #207-2003 standard rating chart.
2.4 results are shown in Table 3 below and in FIGS. 1-3:
TABLE 3 detection results
Whether or not to pass
Example 1 AS2, 100% qualified
Example 2 AS4, 100% qualified
Example 3 AS5, 100% qualified
Example 4 AS3, 100% qualified
Example 5 AS4, 100% qualified
3. Ultrasonic flaw detection
3.1 grade 4 100% flaw detection according to GB/T6402-2008 standard.
3.2 results are shown in Table 4 below:
TABLE 4 ultrasonic inspection test results
Whether or not to pass
Example 1 Grade 4, 100% pass
Example 2 Grade 4, 100% pass
Example 3 Grade 4, 100% pass
Example 4 Grade 4, 100% pass
Example 5 Grade 4, 100% pass
4. Metallographic detection
The metallographic examination results in examples 1-3 are shown in FIGS. 4-6, and all the examination results meet North American die casting society standard NADCA#207-2003.
The foregoing is merely illustrative of the present invention, and the present invention is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present invention.

Claims (7)

1. A preparation method of a sulfur free cutting hot work die steel CX2344 is characterized by comprising the following steps: the sulfur free cutting hot work die steel CX2344 comprises the following chemical components in percentage by weight:
0.36-0.42% of C, 0.80-1.20% of Si, 0.30-0.60% of Mn, 0.08-0.13% of S, less than or equal to 0.020% of P, 4.70-5.50% of Cr, less than or equal to 0.30% of Ni, 0.80-1.20% of V, 1.45-1.75% of Mo, 0.015-0.035% of Al, less than or equal to 0.0004% of H, less than or equal to 0.0030% of O, less than or equal to 0.0200% of N, and the balance of Fe;
the preparation of the chalcogenide free-cutting hot-work die steel CX2344 comprises a smelting process, a forging process and a heat treatment process; after the smelting and casting steel ingot is solidified, carrying out forging treatment on the red-cast steel ingot when the temperature of the steel ingot is less than or equal to 1300 ℃, and keeping the forging temperature at more than or equal to 900 ℃; when forging treatment is carried out, the forging temperature is 1260-950 ℃; after the forging process is finished, utilizing the waste heat after forging of the forging piece to enter an annealing furnace to enter a heat treatment process;
the preparation of the sulfur free cutting hot work die steel CX2344 specifically comprises the following steps:
s1, smelting
S11, proportioning the raw materials according to the chemical components, and baking the ferroalloy in the raw materials at a high temperature;
s12, entering an electric furnace, cleaning a steel ladle before smelting, and baking well, wherein before raw materials in the electric furnace are filled, soot blowing is needed, and carburetion is prevented; 15-17Kg/T of stone dust is added according to the total steelmaking amount at present, then the raw materials prepared in the step S11 are added for melting, a slag former is added for slag formation in the melting process, the molten steel is prevented from being exposed, and the addition amount of the slag former is 1.5-2.0Kg/T according to the total steelmaking amount at present; and using calcium wires for diffusion deoxidation, wherein the adding amount of the calcium wires is 4.8-5.2m/T according to the total steelmaking amount; when the smelting temperature is more than or equal to 1620 ℃, the double pipes are lifted and blown, the wild air valve is opened to perform water pumping and cooling on the cable and the furnace cover lifting cylinder, and the carbon content of the terminal point is controlled to be 0.18%; then entering a reduction period, wherein the reduction method adopted in the reduction period is as follows: adding baked lime 18-22Kg/T and deoxidizer 2-4Kg/T according to the total steelmaking amount, pre-reducing, adding deoxidizer from a furnace door after slagging, blowing argon into the furnace door, stirring for more than or equal to 10min, and thoroughly reducing; regulating Si content to 0.95% before tapping, and tapping to remove slag;
s13, entering an LF furnace, adding 18-22Kg/T of baked lime, 5.5-6.5Kg/T of cap slag and 1.5-2.5Kg/T of fire brick and 2.5Kg/T of deoxidizer into the LF furnace according to the total steelmaking amount, and making white slag, controlling the refining time of the white slag to be more than or equal to 30min, and continuously adding the deoxidizer in the process of maintaining the refining of the white slag so as to maintain a strong reducing atmosphere; sampling when the chemical clearing temperature is more than or equal to 1560 ℃, and adjusting the chemical components according to the content requirements of the chemical components; after the adjustment is completed for at least 10min, deslagging and vacuumizing are carried out; sampling again, and adjusting the chemical composition control target value to be: 0.42% of C, 0.90% of Si, 0.45% of Mn, 4.90% of Cr, 1.44% of Mo, 0.83% of V and 0.095% of S; after chemical components are regulated, when the temperature reaches 1700 ℃, feeding Al wires until the Al content is 0.11%, adding fire bricks, thoroughly breaking slag, and adding sulfur core wires until the S content is 0.095%;
s14, entering a VD furnace, and controlling the ultimate vacuum pressure to be less than or equal to 67Pa and the time to be more than or equal to 12min; the temperature of the hanging bag is 1550-1555 ℃;
s15, pouring, namely cleaning an ingot mould, ensuring that a pouring system is clean and dry, and filling argon into a pouring tube and the mould for 3 minutes before pouring, wherein the amount of casting powder is 2 kg/branch; when in pouring, the ladle hanging temperature is 1550-1555 ℃; controlling the injection temperature and the injection speed, controlling the injection temperature to 1550-1555 ℃, and uniformly feeding 0.3-0.5Kg/T of lanthanum-cerium mixed rare earth metal during casting;
s2, forging
S21, a first sequence: when the temperature of the steel ingot is less than or equal to 1300 ℃, red-feeding the steel ingot to a gas heating furnace section, heating to 1190-1210 ℃, preserving heat for 2.5-3 minutes according to the thickness of the steel ingot per millimeter, and after the heat preservation is finished, carrying out first order, namely pressing the clamp to ensure that phi 400mmX is 650mm, staggering water purifying ports, drawing out and rounding to the same size at the two ends, wherein the forging deformation is less than or equal to 10%, so that the surface of the steel ingot forms compressive stress; heating to 1190-1210 ℃ in a furnace, and preserving heat for 1.5-2 minutes per millimeter according to the thickness of the steel ingot;
s22, second sequence: upsetting to the height H=950 mm, drawing out 820mm and chamfering, returning to the furnace and heating to 1190-1210 ℃, and preserving heat for 1.5-2 minutes according to the thickness of the steel ingot per millimeter;
s23, third procedure: upsetting to a height H=950 mm, flattening 700mm, turning over 90 degrees, pressing 820mm again, chamfering, returning to the furnace, heating to 1190-1210 ℃, and preserving heat for 1.5-2 minutes per millimeter according to the thickness of the steel ingot;
s24, fourth procedure: upsetting to a height H=950 mm, flattening 700mm, turning over 90 degrees, pressing 820mm again, chamfering, returning to the furnace, heating to 1190-1210 ℃, and preserving heat for 1.5-2 minutes per millimeter according to the thickness of the steel ingot;
s25, a fifth procedure: upsetting to a height H=800 mm, drawing and trimming all parts to a ruler, and completing forging to obtain a forging piece;
s3, heat treatment
After forging, utilizing the waste heat of the forged piece after forging to enter an annealing furnace for annealing, wherein the annealing temperature is 850-870 ℃, and the heat preservation time is 2.5-3.5 minutes according to the thickness of the forged piece per millimeter; air cooling is carried out after heat preservation is finished, and an annealed forging piece is obtained;
s4, machining
Machining according to the machining size reserved allowance to obtain a machined die steel plate;
s5, ultra-fine grain treatment
Quenching: heating to 1030 ℃ for 1-2 minutes according to the effective thickness of the plate material per millimeter, quenching into oil, discharging oil at 150-170 ℃, loading into a tempering furnace, tempering at 730-750 ℃ for 2.5-3.0 minutes according to the effective thickness of the plate material per millimeter, discharging from the furnace for air cooling, and obtaining the chalcogenide free-cutting hot work die steel CX2344 after the air cooling is finished.
2. The method for preparing the sulfur-free cutting hot work die steel CX2344, which is characterized in that: the weight percentages of the chemical components are as follows: 0.38% -0.40% of C, 0.90% -1.10% of Si, 0.40% -0.50% of Mn, 0.10% -0.12% of S, less than or equal to 0.020% of P, 5.00% -5.20% of Cr, less than or equal to 0.30% of Ni, 0.90% -1.10% of V, 1.55% -1.65% of Mo, 0.020% -0.030% of Al, less than or equal to 0.0004% of H, less than or equal to 0.0030% of O, less than or equal to 0.0200% of N and the balance of Fe.
3. The method for preparing the sulfur-free cutting hot work die steel CX2344, which is characterized in that: the weight percentages of the chemical components are as follows: 0.39% of C, 1.00% of Si, 0.45% of Mn, 0.11% of S, less than or equal to 0.020% of P, 5.10% of Cr, less than or equal to 0.30% of Ni, 1.00% of V, 1.60% of Mo, 0.025% of Al, less than or equal to 0.0004% of H, less than or equal to 0.0030% of O, less than or equal to 0.0200% of N, and the balance of Fe.
4. The method for preparing the sulfur-free cutting hot work die steel CX2344, which is characterized in that: in the step S11, the ferroalloy is baked at high temperature, namely the ferroalloy is put into a baking furnace to be heated to 730-780 ℃, and the temperature is kept at 730-780 ℃ for at least 6 hours.
5. The method for preparing the sulfur-free cutting hot work die steel CX2344, which is characterized in that: in the step S12, the slag former is a mixture of calcium oxide and aluminum oxide, and the mass ratio of the calcium oxide to the aluminum oxide is 3.5-4.5:1.
6. The method for preparing the sulfur-free cutting hot work die steel CX2344, which is characterized in that: in the step S12, the deoxidizer added during the pre-reduction is fe—si powder.
7. The method for preparing the sulfur-free cutting hot work die steel CX2344, which is characterized in that: in the step S13, the deoxidizer is fe—si powder.
CN202210957357.3A 2022-08-10 2022-08-10 Preparation method of chalcogenide free-cutting hot-work die steel CX2344 Active CN115323288B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210957357.3A CN115323288B (en) 2022-08-10 2022-08-10 Preparation method of chalcogenide free-cutting hot-work die steel CX2344

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210957357.3A CN115323288B (en) 2022-08-10 2022-08-10 Preparation method of chalcogenide free-cutting hot-work die steel CX2344

Publications (2)

Publication Number Publication Date
CN115323288A CN115323288A (en) 2022-11-11
CN115323288B true CN115323288B (en) 2023-05-16

Family

ID=83922390

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210957357.3A Active CN115323288B (en) 2022-08-10 2022-08-10 Preparation method of chalcogenide free-cutting hot-work die steel CX2344

Country Status (1)

Country Link
CN (1) CN115323288B (en)

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112030073A (en) * 2020-08-26 2020-12-04 东北大学 Bismuth-containing free-cutting pre-hardened plastic die steel and preparation method thereof

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4117114B2 (en) * 2001-04-26 2008-07-16 Ｊｆｅテクノワイヤ株式会社 Manufacturing method of welded closed high strength shear reinforcement
CN114540699B (en) * 2022-02-28 2022-12-13 江苏宏晟模具钢材料科技有限公司 High-performance hot-work die steel and preparation method thereof

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112030073A (en) * 2020-08-26 2020-12-04 东北大学 Bismuth-containing free-cutting pre-hardened plastic die steel and preparation method thereof

Also Published As

Publication number Publication date
CN115323288A (en) 2022-11-11

Similar Documents

Publication Publication Date Title
CN108220766B (en) Cr-V hot work die steel and preparation method thereof
CN109266970B (en) High-nitrogen high-chromium plastic die steel and smelting and heat treatment method thereof
CN111961988B (en) Production process and forging method of medium-carbon non-quenched and tempered steel for automobile expansion fracture connecting rod
CN112899560B (en) High-strength gear steel 23CrMnMoS and manufacturing method thereof
CN110273105B (en) High-speed tool steel and preparation method thereof
CN109402498A (en) A kind of high-temperature carburizing pinion steel and its manufacturing method
WO2022228216A1 (en) Steel for high-temperature carburized gear shaft and manufacturing method for steel
CN112159932A (en) Method for manufacturing ultrahigh-strength rare earth 4340 steel
WO2019169548A1 (en) Low-strength cast steel micro-alloyed with rare earth
CN114892094A (en) Pre-hardened mirror plastic die steel and production method thereof
CN114645188A (en) Method for efficiently producing hot-rolled steel strip for 2-4 mm extreme thin-specification high-quality stirring tank with tensile strength of 650MPa
CN103526121A (en) Anti-scratching mandrel material
WO2019029533A1 (en) Cast steel, preparation method for cast steel and use of cast steel
CN114635077A (en) Super austenitic stainless steel and preparation method thereof
CN114959456B (en) Nuclear power SA182F91 valve body and preparation method thereof
CN115323288B (en) Preparation method of chalcogenide free-cutting hot-work die steel CX2344
WO2023137842A1 (en) Die steel having high thermal diffusion coefficient, and preparation method therefor
CN110241358A (en) Novel body structural member die-casting die steel and its preparation process
CN109778073B (en) Free-cutting steel for automobile synchronizer and preparation method thereof
CN116623064A (en) Preparation method of high-strength corrosion-resistant stainless steel X14CrMoS17
CN112962030B (en) Large-specification high-fragment-rate steel and preparation method thereof
CN115821169B (en) High-strength steel and preparation method and application thereof
CN115896634B (en) High-temperature-resistant nonferrous metal die-casting forming die steel material and preparation method thereof
CN115261744B (en) High-toughness low-chromium ferrite stainless steel medium plate and manufacturing method thereof
CN115584435B (en) High-strength steel for cold extrusion molding of heavy cross shaft 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
GR01 Patent grant
GR01 Patent grant