CN117089771B - Magnesium tellurium composite microalloyed gear steel - Google Patents

Magnesium tellurium composite microalloyed gear steel Download PDF

Info

Publication number
CN117089771B
CN117089771B CN202311354328.9A CN202311354328A CN117089771B CN 117089771 B CN117089771 B CN 117089771B CN 202311354328 A CN202311354328 A CN 202311354328A CN 117089771 B CN117089771 B CN 117089771B
Authority
CN
China
Prior art keywords
steel
percent
alloyed
refining
magnesium
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
CN202311354328.9A
Other languages
Chinese (zh)
Other versions
CN117089771A (en
Inventor
白云
杨树峰
刘威
李京社
孙烨
张庆松
车智超
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.)
University of Science and Technology Beijing USTB
Original Assignee
University of Science and Technology Beijing USTB
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 University of Science and Technology Beijing USTB filed Critical University of Science and Technology Beijing USTB
Priority to CN202311354328.9A priority Critical patent/CN117089771B/en
Publication of CN117089771A publication Critical patent/CN117089771A/en
Application granted granted Critical
Publication of CN117089771B publication Critical patent/CN117089771B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/02Ferrous alloys, e.g. steel alloys containing silicon
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C33/00Making ferrous alloys
    • C22C33/04Making ferrous alloys by melting
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/002Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/04Ferrous alloys, e.g. steel alloys containing manganese
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/18Ferrous alloys, e.g. steel alloys containing chromium
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/60Ferrous alloys, e.g. steel alloys containing lead, selenium, tellurium, or antimony, or more than 0.04% by weight of sulfur
    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00Technologies related to metal processing
    • Y02P10/20Recycling

Abstract

The application provides magnesium tellurium composite microalloyed gear steel, and relates to the field of metallurgy. The magnesium-tellurium composite microalloyed gear steel comprises the following components in percentage by mass: 0.16 to 0.22 percent of C, less than or equal to 0.13 percent of Si, 0.80 to 1.60 percent of Mn, 0.02 to 0.03 percent of S, 0 to 0.04 percent of P, 0.95 to 1.35 percent of Cr, 0.01 to 0.024 percent of Te0.01 to 15ppm of Mg, and the balance of Fe and unavoidable impurity elements; the preparation method comprises the following steps: and carrying out electric furnace smelting by using carbon scrap steel and molten iron, and then carrying out LF refining, vacuum degassing, continuous casting and cooling. The magnesium tellurium composite microalloyed gear steel provided by the application considers the Al in the steel at the same time 2 O 3 And MnS, modified with Al 2 O 3 Is core, mnS is shell, and MgAl is used for conversion 2 O 4 Is core and Mn (S, te) is shell.

Description

Magnesium tellurium composite microalloyed gear steel
Technical Field
The application relates to the field of metallurgy, in particular to magnesium-tellurium composite micro-alloyed gear steel.
Background
Gears are an important component of the basic raw materials in "industrial stroma" as a typical base component for manufacturing mechanical transmissions. Compared with the traditional fuel oil automobile, the highest rotating speed of the gear of the gearbox of the new energy automobile is increased from 8000 r/min to 20000 r/min, and the gear steel fatigue performance is more highly required. From the viewpoint of improving the contact fatigue performance of gears, it is required that the gear steel is carburized to have a uniform surface structure and hardness distribution, and that inclusions which can be a crack source are also required. At the same time, the cutting performance of the gear steel is greatly affected by the inclusions. Therefore, the type, the number, the size and the like of nonmetallic inclusion in steel are all important factors influencing the performance of gear steel, and the type of inclusion in 20MnCr5 steel is expressed as Al 2 O 3 And MnS are the dominant.
Al 2 O 3 The presence of inclusions in the steel results in an uneven distribution of the stress field, which results in stress concentrations that make the steel more susceptible to cracking and fatigue fracture when subjected to fatigue loads. When Al is 2 O 3 The size of the inclusions and the transverse-longitudinal ratio of the inclusions become smaller, so that the surface defects of the steel are reduced, and the local stress concentration is relieved, thereby reducing the stress concentration phenomenon when the steel is subjected to fatigue load. Meanwhile, the fine inclusions can improve the grain boundary structure of the steel, so that the grain boundary structure is more uniform, the mechanical property and the deformation resistance of the steel are improved, the fracture risk of the steel when the steel is subjected to fatigue load is reduced, and the fatigue resistance of the steel is improved.
Al in steel 2 O 3 、Cr 2 O 3 And calcium aluminate oxides can greatly reduce the machinability of the steel. Meanwhile, machinability is important in relation to the shape of MnS inclusions, and chain-like and long MnS inclusions may cause defects in steel, so that MnS is controlled to be spindle-like or spherical as much as possible. The spherical sulfide can obviously improve the cutting performance of steel, and the larger the particles, the more obvious the effect is.
At present, researchers use Mg to treat inclusions so as to obtain Al 2 O 3 The core is wrapped with MnS to be converted into MgAl 2 O 4 As a core, but eventually a significant fraction of the individual MnS is present. The scholars use Te to treat the inclusion MnS, and the result is a compound inclusion of which the telluride wraps the MnS, but the growth of the inclusion is uncontrollable, and the optimal tellurium content exists. When Mg and Te are composited, tellurium treatment effect is exerted to the maximum at the same tellurium content. At the same time, the number of inclusions increases and the size becomes smaller.
Disclosure of Invention
The application aims to provide magnesium-tellurium composite micro-alloyed gear steel so as to solve the problems.
In order to achieve the above purpose, the application adopts the following technical scheme:
the magnesium-tellurium composite microalloyed gear steel comprises the following components in percentage by mass:
0.16 to 0.22 percent of C, less than or equal to 0.13 percent of Si, 0.80 to 1.60 percent of Mn, 0.02 to 0.03 percent of S, 0 to 0.04 percent of P, 0.95 to 1.35 percent of Cr, 0.01 to 0.024 percent of Te0.01 to 15ppm of Mg, and the balance of Fe and unavoidable impurity elements;
the preparation method of the magnesium tellurium composite micro-alloyed gear steel comprises the following steps:
carrying out electric furnace smelting by using carbon scrap steel and molten iron, and then carrying out LF refining, vacuum degassing, continuous casting and cooling to obtain the magnesium tellurium composite micro-alloyed gear steel;
the carbon steel scrap comprises the following components in percentage by mass:
c:0.18-0.22%, si:0.08-0.12%, mn:0.5-0.55%, P:0-0.03%, S:0-0.03%, and the balance being Fe and unavoidable impurity elements;
the molten iron comprises the following residual element components in percentage by mass:
C:0.38-0.45%、Si:0.2-0.35%、Mn:0.3-0.4%、P:0-0.13%、S:0 -0.03%;
the carbon steel scrap accounts for 50-70% of the total mass of the carbon steel scrap and the molten iron.
Preferably, in the electric furnace smelting process, the foaming slag forming conditions comprise:
bath temperatureDegree 1545-1585 ℃, caCO 3 The powder spraying amount of the steel is 3-4kg/t, the carrier gas pressure is 0.5-0.7MPa, and the foaming height exceeds 550mm.
Preferably, in the early stage of smelting, the flow of bottom blowing argon is 8-13NL/min, the scrap steel dissolving period is 25-35NL/min, the oxidation period is 15-25NL/min, the smelting end stage is 35-45NL/min, and the smelting time of the electric furnace is 45-50min.
Preferably, the quick lime is added in the LF refining process at 300-500-kg, the refining temperature is 1500-1600 ℃ and the refining time is 30-45 min, so that good fluidity and alkalinity R of the refining slag are ensured to be more than or equal to 3.0.
Preferably, aluminum particles, siC and carbon powder are added in the LF refining process to carry out whole-course diffusion deoxidation, and the white slag refining time is more than or equal to 20min.
Preferably, before and during LF refining, low aluminum ferrosilicon, medium carbon ferromanganese and low carbon ferrochrome are used for fine adjustment and alloying of molten steel components, and pure magnesium wires are fed to perform Mg treatment before the molten steel is discharged.
Preferably, the argon pressure is controlled to be 0.15-0.25 MPa during the vacuum degassing, and soft blowing is carried out for 25-35 min; the bottom blowing is matched in the vacuumizing process, so that the steel slag is prevented from being strongly rolled, and the VD vacuum time is 20-30 min; after VD is broken, sulfur wires and pure tellurium cored wires are fed, the tellurium-sulfur ratio is controlled to be between 0.5 and 0.8, S is less than or equal to 0.025 percent, and soft blowing is carried out for 10 to 20 minutes.
Preferably, before the continuous casting is started, tundish gas replacement, sealing and plastering of rock wool around a tundish and a ladle cover are performed, and a slag bleaching port is sealed by the rock wool;
the nozzle uses an argon seal and requires vertical, centered immersion levels of 100-130 a mm a.
Preferably, in the continuous casting process, the baking time of the tundish is 5-7 h, the baking temperature is 1000-1100 ℃, and the hoisting temperature is 1595-1605 ℃;
a cold water amount of 115-125m 3 And/h, equipped with electromagnetic stirring: current 230-240A, frequency 2.5-2.8Hz; the specific water content of the secondary cooling water is 0.35-0.38L/kg;
the superheat degree of tundish casting is 20-35 ℃, and the continuous casting pulling speed is 0.55-m/min-0.75-m/min.
Preferably, the casting blank obtained by continuous casting is taken off line and then enters a slow cooling pit for slow cooling.
Compared with the prior art, the application has the beneficial effects that:
the magnesium tellurium composite microalloyed gear steel provided by the application considers the Al in the steel at the same time 2 O 3 And MnS, modified with Al 2 O 3 The core is wrapped with MnS to be converted into MgAl 2 O 4 Is core and Mn (S, te) is shell. Wherein the average size of oxide inclusions is reduced from 5.19 mu m to 2.11 mu m, and the number density is reduced from 88 pieces/mm 2 Reduced to 43/mm 2 . The MnS modification is to form a compound inclusion of the telluride coated MnS, the aspect ratio of the inclusion is reduced from 3.56 to 1.69, and the improvement of cutting performance is facilitated. The fatigue strength of the steel is improved from 748 MPa to 1229 MPa. The Mg content is between 10 and 15ppm, and the Te content is between 0.01 and 0.024 percent.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope of the present application.
FIG. 1 is a diagram showing the morphology and composition analysis of inclusion in the initial stage of LF refining in example 3;
FIG. 2 is a diagram showing the morphology and composition analysis of the LF end inclusion in example 3;
FIG. 3 is a chart showing morphology and composition analysis of the VD end point inclusion of example 3.
Detailed Description
Firstly, the technical scheme provided by the application is integrally stated:
the magnesium-tellurium composite microalloyed gear steel comprises the following components in percentage by mass:
0.16 to 0.22 percent of C, less than or equal to 0.13 percent of Si, 0.80 to 1.60 percent of Mn, 0.02 to 0.03 percent of S, 0 to 0.04 percent of P, 0.95 to 1.35 percent of Cr, 0.01 to 0.024 percent of Te0.01 to 15ppm of Mg, and the balance of Fe and unavoidable impurity elements.
Alternatively, the content of C in the magnesium tellurium composite micro-alloyed gear steel may be any value between 0.16%, 0.17%, 0.18%, 0.19%, 0.20%, 0.21%, 0.22% or 0.16% -0.22%; the Si content may be any value of 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.10%, 0.11%, 0.12%, 0.13% or less than or equal to 0.13%; the Mn content may be any value between 0.80%, 0.90%, 1.00%, 1.10%, 1.20%, 1.30%, 1.40%, 1.50%, 1.60% or 0.80% -1.60%; the content of S may be any value between 0.02%, 0.022%, 0.024%, 0.026%, 0.028%, 0.030%, or 0.02% -0.03%; the content of P may be any value between 0, 0.01%, 0.02%, 0.03%, 0.04%, or 0% -0.04%; the Cr content may be any value between 0.95%, 1.00%, 1.05%, 1.10%, 1.15%, 1.20%, 1.25%, 1.30%, 1.35% or 0.95% -1.35%; the Te content may be any value between 0.010%, 0.012%, 0.014%, 0.016%, 0.018%, 0.020%, 0.022%, 0.024% or 0.01% -0.024%; the content of Mg may be 10 ppm, 11 ppm, 12ppm, 13 ppm, 14 ppm, 15ppm or any value between 10 and 15 ppm; the balance of Fe and unavoidable impurity elements.
The application also provides a preparation method of the magnesium tellurium composite micro-alloyed gear steel, which comprises the following steps:
and carrying out electric furnace smelting by using carbon scrap steel and molten iron, and then carrying out LF refining, vacuum degassing, continuous casting and cooling to obtain the magnesium tellurium composite micro-alloyed gear steel.
In an alternative embodiment, the carbon steel scrap comprises, in mass percent:
c:0.18-0.22%, si:0.08-0.12%, mn:0.5-0.55%, P:0-0.03%, S:0-0.03%, and the balance being Fe and unavoidable impurity elements;
the molten iron comprises the following residual element components in percentage by mass:
C:0.38-0.45%、Si:0.2-0.35%、Mn:0.3-0.4%、P:0-0.13%、S:0 -0.03%;
the carbon steel scrap accounts for 50-70% of the total mass of the carbon steel scrap and the molten iron.
Optionally, the carbon scrap comprises any value between 50%, 55%, 60%, 65%, 70% or 50% -70% of the total mass of the carbon scrap and the molten iron.
In an alternative embodiment, the conditions of foaming slag during the electric furnace smelting include:
bath temperature 1545-1585 ℃, caCO 3 The powder spraying amount of the steel is 3-4kg/t, the carrier gas pressure is 0.5-0.7MPa, and the foaming height exceeds 550mm.
Alternatively, the bath temperature may be any value, caCO, of 1545 ℃, 1550 ℃, 1555 ℃, 1560 ℃, 1565 ℃, 1570 ℃, 1575 ℃, 1580 ℃, 1585 ℃ or 1545-1585 DEG C 3 The powder spraying amount of (3) kg/t steel, 3.5kg/t steel, 4kg/t steel or 3-4kg/t steel, and the carrier gas pressure may be any value between 0.5 MPa, 0.6 MPa, 0.7MPa or 0.5-0.7 MPa.
In an alternative embodiment, in the smelting process of the electric furnace, the flow of bottom blowing argon is 8-13NL/min in the earlier stage of smelting, the scrap steel dissolving period is 25-35NL/min, the oxidation period is 15-25NL/min, the smelting period is 35-45NL/min in the final stage of smelting, and the smelting time of the electric furnace is 45-50min.
Optionally, in the early stage of smelting, the flow of bottom blowing argon gas may be any value of 8 NL/min, 9 NL/min, 10 NL/min, 11 NL/min, 12 NL/min, 13NL/min or 8-13NL/min, the scrap steel clearing period may be any value of 25NL/min, 30 NL/min, 35NL/min or 25-35NL/min, the oxidizing period may be any value of 15 NL/min, 20 NL/min, 25NL/min or 15-25NL/min, the smelting end stage may be any value of 35NL/min, 40 NL/min, 45NL/min or 35-45NL/min, and the electric furnace smelting time may be any value of 45 min, 46 min, 47 min, 48 min, 49 min, 50min or 45-50min.
In an alternative embodiment, the quick lime is added in the LF refining process at 300-500kg, the refining temperature is 1500-1600 ℃ and the refining time is 30-45 min, so that good fluidity and the alkalinity R of the refining slag are ensured to be more than or equal to 3.0.
Alternatively, the quicklime may be added in an amount of 300 kg, 400 kg, 500kg or 300-500kg, the refining temperature may be 1500 ℃, 1550 ℃, 1600 ℃ or 1500-1600 ℃ and the refining time may be 30 min, 35 min, 40 min, 45 min or 30-45 min.
In an optional implementation mode, aluminum particles, siC and carbon powder are added in the LF refining process to carry out whole-course diffusion deoxidation, and the white slag refining time is more than or equal to 20 min;
before and during LF refining, low-aluminum ferrosilicon, medium-carbon ferromanganese and low-carbon ferrochrome are used for fine adjustment and alloying of molten steel components, and pure magnesium wires are fed to carry out Mg treatment before the molten steel is discharged.
In an alternative embodiment, the argon pressure is controlled between 0.15 and 0.25 MPa during the vacuum degassing, and the soft blowing is continued for 25 to 35 min; the bottom blowing is matched in the vacuumizing process, so that the steel slag is prevented from being strongly rolled, and the VD vacuum time is 20-30 min; after VD is broken, sulfur wires and pure tellurium cored wires are fed, the tellurium-sulfur ratio is controlled to be between 0.5 and 0.8, S is less than or equal to 0.025 percent, and soft blowing is carried out for 10 to 20 minutes.
Optionally, the argon pressure is controlled to any value between 0.15 MPa, 0.16 MPa, 0.17 MPa, 0.18 MPa, 0.19 MPa, 0.20 MPa, 0.21 MPa, 0.22 MPa, 0.23 MPa, 0.24 MPa, 0.25 MPa or 0.15-0.25 MPa during the vacuum degassing, and the soft blowing is continued for any value between 25 min, 30 min, 35 min or 25-35 min; in the vacuumizing process, bottom blowing is matched to avoid strong rolling of steel slag, and the VD vacuum time can be any value between 20min, 25 min, 30 min or 20-30 min; after VD is broken, a sulfur line and a pure tellurium cored wire are fed, the tellurium-sulfur ratio is controlled to be any value of 0.5, 0.6, 0.7, 0.8 or 0.5-0.8, S is less than or equal to 0.025%, and the soft blowing time can be any value of 10 min, 15 min, 20min or 10-20min.
In an alternative embodiment, the tundish gas replacement, the tundish and the surrounding rock wool sealing and plastering are performed before continuous casting and pouring, and the slag floating port is sealed by rock wool;
the nozzle uses an argon seal and requires vertical, centered immersion levels of 100-130 a mm a.
Alternatively, the immersion liquid level depth may be any value between 100 mm, 110 mm, 120 mm, 130mm, or 100-130mm.
In an alternative embodiment, in the continuous casting process, the ladle baking time is 5-7 h, the ladle baking temperature is 1000-1100 ℃, and the ladle hanging temperature is 1595-1605 ℃;
optionally, the baking time of the middle ladle can be any value between 5h, 6 h, 7 h or 5-7 h, the baking temperature can be any value between 1000 ℃, 1050 ℃, 1100 ℃ or 1000-1100 ℃, and the hanging ladle temperature is controlled to be any value between 1595 ℃, 1600 ℃, 1605 ℃ or 1595-1605 ℃;
a cold water amount of 115-125m 3 And/h, equipped with electromagnetic stirring: current 230-240A at a frequency of 2.5-2.8Hz; the specific water content of the secondary cooling water is 0.35-0.38L/kg;
alternatively, a cold water volume may be 115 m 3 /h、120 m 3 /h、125 m 3 /h or 115-125m 3 The electromagnetic stirring current can be any value between 230A, 235A, 240A or 230-240A, and the frequency can be any value between 2.5 Hz, 2.6 Hz, 2.7 Hz, 2.8Hz or 2.5-2.8Hz; the specific water content of the secondary cooling water can be any value between 0.35L/kg, 0.36L/kg, 0.37L/kg, 0.38L/kg or 0.35-0.38L/kg;
the superheat degree of pouring of the tundish is controlled at 20-35 ℃, and the continuous casting pulling speed is 0.55-m/min-0.75-m/min;
and (3) taking the casting blank obtained by continuous casting off line, and then, entering a slow cooling pit for slow cooling.
Alternatively, the ladle pouring superheat may be any value between 20 ℃, 25 ℃, 30 ℃, 35 ℃, or 20-35 ℃, and the continuous casting pulling rate may be any value between 0.55m/min, 0.60 m/min, 0.65 m/min, 0.70 m/min, 0.75 m/min, or 0.55m/min-0.75 m/min.
Embodiments of the present application will be described in detail below with reference to specific examples, but it will be understood by those skilled in the art that the following examples are only for illustrating the present application and should not be construed as limiting the scope of the present application. The specific conditions are not noted in the examples and are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or apparatus used were conventional products commercially available without the manufacturer's attention.
Example 1
The embodiment provides magnesium tellurium composite micro-alloyed gear steel which comprises the following components in percentage by mass:
0.19% of C, 0.13% of Si, 0.91% of Mn, 0.02% of S, 0.02% of P, 1.18% of Cr, 0.01% of Te0.01% of Mg, 10 ppm of Fe and unavoidable impurity elements as the rest.
The preparation method comprises the following steps:
1) Smelting in an electric furnace:
and (3) melting scrap steel in the electric furnace smelting process, removing redundant alloy elements, adding Mn and Cr element alloy, and adjusting to a target value. Residual elemental composition of molten iron: c:0.42%, si:0.28%, mn:0.35%: p:0.09%, S:0.026%; carbon steel scrap: c:0.20%, si:0.10%, mn, 0.51%: p:0.008%, S:0.012%; the proportion of scrap steel to molten iron is 65-35 wt%.
The optimal technological condition of foaming slag is the molten pool temperature of 1565 ℃, caCO 3 The powder spraying amount of the steel is 3.5kg/t, the carrier gas pressure is 0.6 MPa, and the foaming height is more than 550mm. In the earlier stage of smelting, the flow of bottom-blown argon is 10 NL/min, the scrap steel clearing period is 28 NL/min, the oxidation period is 20 NL/min, the smelting end stage is 40 NL/min, and the whole smelting time is 48 min.
2) LF refining:
after tapping by the electric furnace, hoisting the ladle to an LF station for refining, and after the ladle is ready, starting to introduce argon. After entering the LF furnace, lime 450 and kg are added according to the process slag condition, the slag condition is timely adjusted, good fluidity and alkalinity R of refined slag are ensured to be more than or equal to 3.0, refining temperature is 1550 ℃, and refining time is 38 min. In the power transmission and refining process, proper amount of aluminum particles, siC and carbon powder are added for full-course diffusion deoxidation, and the refining time of white slag is 20min. Aluminum particles are used for diffusion deoxidation, and the argon blowing stirring intensity and refining slag system in the refining process are controlled, so that the aluminum particles can well desulfurize and remove impurities in molten steel. Before and during refining, low-aluminum ferrosilicon, medium-carbon ferromanganese, low-carbon ferrochrome and the like are used for fine adjustment and alloying of molten steel components, so that the hit rate of the components is improved. Before exiting, pure magnesium wire is fed to carry out Mg treatment, and then molten steel with proper composition and temperature is fed into a VD station.
3) VD (vacuum degassing):
the argon pressure was controlled at 0.2 MPa during VD, and soft blowing continued for about 30 min. And in the vacuumizing process, bottom blowing is matched to avoid strong rolling of steel slag, and the VD vacuum time is 25 min. After VD is broken, sulfur wires and pure tellurium cored wires are fed, and the tellurium-sulfur ratio is 0.5. Soft blowing for 15 min, and pouring after refining.
4) Continuous casting:
before continuous casting, making tundish gas replacement, sealing rock wool around the tundish and the ladle cover, plastering mud, and sealing rock wool such as a slag drift. The nozzle (argon seal) is required to be vertical and centered, and immersed to a liquid level of 120 a mm a. The baking time of the tundish is 5h, and the baking temperature is required to be 1000 ℃. The temperature of the hanging bag is controlled at 1600 ℃. A cold water quantity of 120m 3 And/h, equipped with electromagnetic stirring: current 240A, frequency 2.8Hz; the specific water quantity of the secondary cooling water is 0.38L/kg. In order to ensure the internal quality of the casting blank, the superheat degree of tundish casting is controlled at 25 ℃, and the continuous casting pulling speed is 0.65 m/min.
5) And (3) cooling:
and (5) taking off the casting blank obtained by continuous casting, and then feeding the casting blank into a slow cooling pit for slow cooling.
Fatigue strength detection: the test is carried out by using a rotary bending fatigue tester, the frequency is 80 Hz, the stress ratio R is 0.1, and the number of complete fracture or cycle of the test sample reaches 1X 10 7 The test was terminated a second time and the fatigue strength of the steel was 1023 MPa.
Example 2
The embodiment provides magnesium tellurium composite micro-alloyed gear steel which comprises the following components in percentage by mass:
0.19% of C, 0.13% of Si, 0.91% of Mn, 0.03% of S, 0.02% of P, 1.18% of Cr, 0.024% of Te0.024% of Mg, 15ppm of Mg, and the balance of Fe and unavoidable impurity elements.
The preparation method comprises the following steps:
1) Smelting in an electric furnace:
and (3) melting scrap steel in the electric furnace smelting process, removing redundant alloy elements, adding Mn and Cr element alloy, and adjusting to a target value. Residual elemental composition of molten iron: c:0.42%, si:0.28%, mn:0.35%: p:0.09%, S:0.036%; carbon steel scrap: c:0.20%, si:0.10%, mn, 0.51%: p:0.008%, S: 0.022; the proportion of scrap steel to molten iron is 65-35 wt%.
The optimal technological condition of foaming slag is the molten pool temperature of 1565 ℃, caCO 3 The powder spraying amount of the steel is 3.5kg/t, the carrier gas pressure is 0.6 MPa, and the foaming height exceeds 550mm. In the earlier stage of smelting, the flow of bottom-blown argon is 10 NL/min, the scrap steel clearing period is 28 NL/min, the oxidation period is 20 NL/min, the smelting end stage is 40 NL/min, and the whole smelting time is 48 min.
2) LF refining:
after tapping by the electric furnace, hoisting the ladle to an LF station for refining, and after the ladle is ready, starting to introduce argon. After entering the LF furnace, according to the process slag condition, lime 300-500-kg and a proper amount of slag melting agent are added, so that the slag condition is timely adjusted, and good fluidity and alkalinity R of refining slag are ensured to be more than or equal to 3.0. In the power transmission and refining process, proper amount of aluminum particles, siC and carbon powder are added for full-course diffusion deoxidation, and the refining time of white slag is 20min. Aluminum particles are used for diffusion deoxidation, and the argon blowing stirring intensity and refining slag system in the refining process are controlled, so that the aluminum particles can well desulfurize and remove impurities in molten steel. Before and during refining, low-aluminum ferrosilicon, medium-carbon ferromanganese, low-carbon ferrochrome and the like are used for fine adjustment and alloying of molten steel components, so that the hit rate of the components is improved. Before exiting, pure magnesium wire is fed to carry out Mg treatment, and then molten steel with proper composition and temperature is fed into a VD station.
3) VD (vacuum degassing):
the argon pressure was controlled at 0.2 MPa during VD, and soft blowing continued for about 30 min. And in the vacuumizing process, bottom blowing is matched to avoid strong rolling of steel slag, and the VD vacuum time is 25 min. After VD is broken, sulfur wires and pure tellurium cored wires are fed, and the tellurium-sulfur ratio is controlled to be 0.8. Soft blowing for 15 min, and pouring after refining.
4) Continuous casting:
before continuous casting, making tundish gas replacement, sealing rock wool around the tundish and the ladle cover, plastering mud, and sealing rock wool such as a slag drift. The nozzle (argon seal) is required to be vertical and centered, and immersed to a liquid level of 120 a mm a. The baking time of the tundish is 5h, and the baking temperature is required to be 1000 ℃. Hanging deviceThe pack temperature was controlled at 1600 ℃. A cold water quantity of 120m 3 And/h, equipped with electromagnetic stirring: current 240A, frequency 2.8Hz; the specific water quantity of the secondary cooling water is 0.38L/kg. In order to ensure the internal quality of the casting blank, the superheat degree of tundish casting is controlled at 25 ℃, and the continuous casting pulling speed is 0.65 m/min.
5) And (3) cooling:
and (5) taking off the casting blank obtained by continuous casting, and then feeding the casting blank into a slow cooling pit for slow cooling.
Fatigue strength detection: the test is carried out by using a rotary bending fatigue tester, the frequency is 80 Hz, the stress ratio R is 0.1, and the number of complete fracture or cycle of the test sample reaches 1X 10 7 The test was terminated a second time, the fatigue strength of the steel 1118 MPa.
Example 3
The embodiment provides magnesium tellurium composite micro-alloyed gear steel which comprises the following components in percentage by mass:
0.19% of C, 0.13% of Si, 0.91% of Mn, 0.03% of S, 0.02% of P, 1.18% of Cr, 0.02% of Te0.02% of Mg, 12ppm of Fe and unavoidable impurity elements as the rest.
The preparation method comprises the following steps:
1) Smelting in an electric furnace:
and (3) melting scrap steel in the electric furnace smelting process, removing redundant alloy elements, adding Mn and Cr element alloy, and adjusting to a target value. Residual elemental composition of molten iron: c:0.42%, si:0.28%, mn:0.35%: p:0.09%, S:0.036%; carbon steel scrap: c:0.20%, si:0.10%, mn, 0.51%: p:0.008%, S: 0.022; the proportion of scrap steel to molten iron is 65-35 wt%.
The optimal technological condition of foaming slag is the molten pool temperature of 1565 ℃, caCO 3 The powder spraying amount of the steel is 3.5kg/t, the carrier gas pressure is 0.6 MPa, and the foaming height exceeds 550mm. In the earlier stage of smelting, the flow of bottom-blown argon is 10 NL/min, the scrap steel clearing period is 28 NL/min, the oxidation period is 20 NL/min, the smelting end stage is 40 NL/min, and the whole smelting time is 48 min.
2) LF refining:
after tapping by the electric furnace, hoisting the ladle to an LF station for refining, and after the ladle is ready, starting to introduce argon. After entering the LF furnace, according to the process slag condition, lime 300-500-kg and a proper amount of slag melting agent are added, so that the slag condition is timely adjusted, and good fluidity and alkalinity R of refining slag are ensured to be more than or equal to 3.0. In the power transmission and refining process, proper amount of aluminum particles, siC and carbon powder are added for full-course diffusion deoxidation, and the refining time of white slag is more than or equal to 20min. Aluminum particles are used for diffusion deoxidation, and the argon blowing stirring intensity and refining slag system in the refining process are controlled, so that the aluminum particles can well desulfurize and remove impurities in molten steel. Before and during refining, low-aluminum ferrosilicon, medium-carbon ferromanganese, low-carbon ferrochrome and the like are used for fine adjustment and alloying of molten steel components, so that the hit rate of the components is improved. Before exiting, pure magnesium wire is fed to carry out Mg treatment, and then molten steel with proper composition and temperature is fed into a VD station.
3) VD (vacuum degassing):
the argon pressure was controlled at 0.2 MPa during VD, and soft blowing continued for about 30 min. And in the vacuumizing process, bottom blowing is matched to avoid strong rolling of steel slag, and the VD vacuum time is 25 min. After VD is broken, sulfur wires and pure tellurium cored wires are fed, and the tellurium-sulfur ratio is controlled to be 0.6. Soft blowing for 15 min, and pouring after refining.
4) Continuous casting:
before continuous casting, making tundish gas replacement, sealing rock wool around the tundish and the ladle cover, plastering mud, and sealing rock wool such as a slag drift. The nozzle (argon seal) is required to be vertical and centered, and immersed to a liquid level of 120 a mm a. The baking time of the tundish is 5 hours, and the baking temperature is required to be 1000 ℃. The temperature of the hanging bag is controlled at 1600 ℃. A cold water volume of 120m 3 And/h, equipped with electromagnetic stirring: current 240A, frequency 2.8Hz; the specific water quantity of the secondary cooling water is 0.38L/kg. In order to ensure the internal quality of the casting blank, the superheat degree of tundish casting is controlled at 25 ℃, and the continuous casting pulling speed is 0.65 m/min.
5) And (3) cooling:
and (5) taking off the casting blank obtained by continuous casting, and then feeding the casting blank into a slow cooling pit for slow cooling.
Fatigue strength detection: the test was carried out using a rotary bending fatigue tester at a frequency of 80 Hz and a stress ratio R of 0.1, and the test was terminated when the test piece was completely broken or the number of cycles reached 1X 107, and the fatigue strength of the steel was 1229 MPa.
Comparative example
The basic steel comprises C0.19%, si0.13%, mn0.91%, S0.03%, P0.02%, cr1.18%, and Fe and unavoidable impurity elements in balance.
Control tests were carried out on the base steel as a test base, and the test steels with different Mg and Te contents were shown in Table 1 for fatigue strength:
TABLE 1 Table of ingredients of test steels with different Mg and Te contents
The detection method comprises the following steps:
1) Preparing a metallographic sample: the steel sample obtained in each process is processed to remove the surface iron scale, and the steel sample is cut into 10 multiplied by 10 mm by adopting wire cutting 3 Cube samples of (2).
2) Morphology and type of inclusions: and (3) observing the metallographic sample of the prepared steel sample by adopting a metallographic optical microscope and a scanning electron microscope, and determining inclusion components by combining an EDS (electronic discharge spectrometry) spectrometer.
3) Number and size of inclusions: the metallographic sample of the prepared steel sample is used for counting the size distribution, the length-width ratio and the like of the inclusions by utilizing an inclusion automatic analysis system.
4) And (3) component detection: and detecting the contents of Mg and Te elements in the steel by utilizing ICP.
5) Fatigue strength detection: the test is carried out by using a rotary bending fatigue tester, the frequency is 80 Hz, the stress ratio R is 0.1, and the number of complete fracture or cycle of the test sample reaches 1X 10 7 The test was terminated at times.
Sampling scheme:
in order to ensure the reliability of the sampling analysis result, three heats of 20MnCr5 gear steel are continuously sampled in the experiment. The specific sampling scheme is shown in Table 2, and cake samples are taken at the initial stage of LF refining, the final stage of LF and the final stage of VD respectively. As shown in table 2:
table 2 sampling protocol
Experimental results:
taking example 3 as an example, fig. 1 is an analysis chart of the morphology and composition of inclusions at the initial stage (No. 1) of LF refining, fig. 2 is an analysis chart of the morphology and composition of inclusions at the final stage (No. 2) of LF, and fig. 3 is an analysis chart of the morphology and composition of inclusions at the final stage (No. 3) of VD.
In the initial stage of LF refining, inclusions in steel are mainly Al 2 O 3 -MnS; after LF feeding magnesium wire, inclusions mainly comprise MnS and Al taking the inclusions as cores 2 O 3 -MgO-MnS, mg being effective to modify the shape of the manganese sulphide from elongated to spherical after treatment; when reaching the VD end point, composite inclusion containing Te appears, and the core of the inclusion is Al 2 O 3 The size of the manganese sulfide is effectively reduced after the MgO and Te are treated.
Comparative example 1
12ppm of Mg was added with the base steel as the test base.
Oxide inclusions having an average size of 4.58 [ mu ] m and a number density of 77 pieces/mm 2 The method comprises the steps of carrying out a first treatment on the surface of the The aspect ratio of the inclusion containing manganese sulfide was 2.56; the fatigue strength was 956 MPa.
Comparative example 2
100 ppm Te was added with the base steel as the test base.
Oxide inclusions having an average size of 4.97 μm and a number density of 94 pieces/mm 2 The method comprises the steps of carrying out a first treatment on the surface of the The aspect ratio of the inclusion containing manganese sulfide was 2.93; the fatigue strength was 862 MPa.
Comparative example 3
6ppm of Mg and 55 ppm of Te were added based on the base steel as a test base.
Oxide inclusions having an average size of 5.34 [ mu ] m and a number density of 105 pieces/mm 2 The method comprises the steps of carrying out a first treatment on the surface of the The aspect ratio of the inclusion containing manganese sulfide was 3.29; the fatigue strength was 834 MPa.
Comparative example 4
30ppm of Mg and 350 ppm of Te were added on the basis of the test using the base steel.
Oxide inclusions having an average size of 4.01 [ mu ] m and a number density of 61 pieces/mm 2 The method comprises the steps of carrying out a first treatment on the surface of the The aspect ratio of the inclusion containing manganese sulfide was 2.13; the fatigue strength was 986 MPa.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present application, and not for limiting the same; although the application has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the application.
Furthermore, those skilled in the art will appreciate that while some embodiments herein include some features but not others included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the application and form different embodiments. For example, in the claims below, any of the claimed embodiments may be used in any combination. The information disclosed in this background section is only for enhancement of understanding of the general background of the application and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

Claims (10)

1. The magnesium tellurium composite micro-alloyed gear steel is characterized by comprising the following components in percentage by mass:
0.16 to 0.22 percent of C, less than or equal to 0.13 percent of Si, 0.80 to 1.60 percent of Mn, 0.02 to 0.03 percent of S, 0 to 0.04 percent of P, 0.95 to 1.35 percent of Cr, 0.01 to 0.024 percent of Te, 10 to 15ppm of Mg, and the balance of Fe and unavoidable impurity elements;
the preparation method of the magnesium tellurium composite micro-alloyed gear steel comprises the following steps:
carrying out electric furnace smelting by using carbon scrap steel and molten iron, and then carrying out LF refining, vacuum degassing, continuous casting and cooling to obtain the magnesium tellurium composite micro-alloyed gear steel;
the carbon steel scrap comprises the following components in percentage by mass:
c:0.18-0.22%, si:0.08-0.12%, mn:0.5-0.55%, P:0-0.03%, S:0-0.03%, and the balance being Fe and unavoidable impurity elements;
the molten iron comprises the following residual element components in percentage by mass:
C:0.38-0.45%、Si:0.2-0.35%、Mn:0.3-0.4%、P:0-0.13%、S:0-0.03%;
the carbon steel scrap accounts for 50-70% of the total mass of the carbon steel scrap and the molten iron.
2. The magnesium tellurium composite micro-alloyed gear steel according to claim 1, wherein the conditions of foaming slag in the electric furnace smelting process include:
bath temperature 1545-1585 ℃, caCO 3 The powder spraying amount of the steel is 3-4kg/t, the carrier gas pressure is 0.5-0.7MPa, and the foaming height is more than 550mm.
3. The magnesium tellurium composite micro-alloyed gear steel according to claim 1, wherein in the smelting process of the electric furnace, the flow of bottom blowing argon is 8-13NL/min in the earlier stage of smelting, the scrap steel clearing period is 25-35NL/min, the oxidation period is 15-25NL/min, the smelting period is 35-45NL/min in the final stage of smelting, and the smelting time of the electric furnace is 45-50min.
4. The magnesium tellurium composite micro-alloyed gear steel according to claim 1, wherein 300-500kg of quicklime is added in the LF refining process, the refining temperature is 1500-1600 ℃, the refining time is 30-45 min, and good fluidity and alkalinity R of refined slag are guaranteed to be more than or equal to 3.0.
5. The magnesium tellurium composite micro-alloyed gear steel according to claim 1, wherein aluminum particles, siC and carbon powder are added in the LF refining process to perform whole-course diffusion deoxidation, and the white slag refining time is more than or equal to 20min.
6. The magnesium tellurium composite micro-alloyed gear steel according to claim 1, wherein before and during the LF refining, low aluminum ferrosilicon, medium carbon ferromanganese and low carbon ferrochrome are used to fine tune and alloy the molten steel components, and pure magnesium wire is fed to perform Mg treatment before the steel is discharged.
7. The magnesium tellurium composite micro-alloyed gear steel according to claim 1, wherein the argon pressure is controlled to be 0.15-0.25 MPa during the vacuum degassing, and the soft blowing is continued for 25-35 min; the bottom blowing is matched in the vacuumizing process, so that the steel slag is prevented from being strongly rolled, and the VD vacuum time is 20-30 min; after VD is broken, sulfur wires and pure tellurium cored wires are fed, the tellurium-sulfur ratio is controlled between 0.2 and 0.8, S is less than or equal to 0.025 percent, and soft blowing is carried out for 10 to 20 minutes.
8. The magnesium tellurium composite micro-alloyed gear steel according to claim 1, wherein tundish gas replacement, tundish and surrounding rock wool sealing and plaster are carried out before continuous casting, and a slag drift port is sealed by rock wool;
the nozzle is sealed by argon and is required to be vertical and centered, and the immersion liquid level depth is 100-130mm.
9. The magnesium tellurium composite micro-alloyed gear steel according to claim 1, wherein in the continuous casting process, the tundish baking time is 5-7 h, the baking temperature is 1000-1100 ℃, and the tundish hanging temperature is 1595-1605 ℃;
a cold water volume of 115-125m 3 And/h, equipped with electromagnetic stirring: 230-240A of current with the frequency of 2.5-2.8Hz; the specific water content of the secondary cooling water is 0.35-0.38L/kg;
the superheat degree of tundish casting is 20-35 ℃, and the continuous casting pulling speed is 0.55m/min-0.75 m/min.
10. The magnesium tellurium composite micro-alloyed gear steel according to any one of claims 1 to 9, wherein the cast slab obtained by continuous casting is put down and then put into a pit for slow cooling.
CN202311354328.9A 2023-10-19 2023-10-19 Magnesium tellurium composite microalloyed gear steel Active CN117089771B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202311354328.9A CN117089771B (en) 2023-10-19 2023-10-19 Magnesium tellurium composite microalloyed gear steel

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202311354328.9A CN117089771B (en) 2023-10-19 2023-10-19 Magnesium tellurium composite microalloyed gear steel

Publications (2)

Publication Number Publication Date
CN117089771A CN117089771A (en) 2023-11-21
CN117089771B true CN117089771B (en) 2023-12-15

Family

ID=88783726

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202311354328.9A Active CN117089771B (en) 2023-10-19 2023-10-19 Magnesium tellurium composite microalloyed gear steel

Country Status (1)

Country Link
CN (1) CN117089771B (en)

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004107694A (en) * 2002-09-13 2004-04-08 Kobe Steel Ltd Carburizing steel material and carburized component
CN101652494A (en) * 2007-10-24 2010-02-17 新日本制铁株式会社 Carbonitrided induction-hardened steel part with excellent rolling contact fatigue strength at high temperature and process for producing the same
CN104884660A (en) * 2012-12-28 2015-09-02 新日铁住金株式会社 Steel for carburizing
JP2017133052A (en) * 2016-01-26 2017-08-03 新日鐵住金株式会社 Case hardened steel excellent in coarse particle prevention property, fatigue property and machinability during carburization and manufacturing method therefor
CN107406943A (en) * 2015-03-31 2017-11-28 新日铁住金株式会社 Surface hardened layer steel part
JPWO2020040190A1 (en) * 2018-08-24 2021-04-08 日本製鉄株式会社 Manufacturing method of steel materials, forged heat-treated products, and forged heat-treated products
CN114892070A (en) * 2022-04-02 2022-08-12 承德建龙特殊钢有限公司 Sulfur-containing gear steel and production method thereof

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004107694A (en) * 2002-09-13 2004-04-08 Kobe Steel Ltd Carburizing steel material and carburized component
CN101652494A (en) * 2007-10-24 2010-02-17 新日本制铁株式会社 Carbonitrided induction-hardened steel part with excellent rolling contact fatigue strength at high temperature and process for producing the same
CN104884660A (en) * 2012-12-28 2015-09-02 新日铁住金株式会社 Steel for carburizing
CN107406943A (en) * 2015-03-31 2017-11-28 新日铁住金株式会社 Surface hardened layer steel part
JP2017133052A (en) * 2016-01-26 2017-08-03 新日鐵住金株式会社 Case hardened steel excellent in coarse particle prevention property, fatigue property and machinability during carburization and manufacturing method therefor
JPWO2020040190A1 (en) * 2018-08-24 2021-04-08 日本製鉄株式会社 Manufacturing method of steel materials, forged heat-treated products, and forged heat-treated products
CN114892070A (en) * 2022-04-02 2022-08-12 承德建龙特殊钢有限公司 Sulfur-containing gear steel and production method thereof

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
20MnCr5齿轮钢全流程夹杂物分析;白旭旭;《钢铁钒钛》;第43卷(第6期);143-148 *
20MnCr5齿轮钢连铸坯中硫化物三维形貌的解析;张晓宇;《冶金分析》;第42卷(第8期);13-19 *
硫化物改质对20MnCr5齿轮钢夹杂物和切削性能的影响;尉文超;《钢铁》;第57卷(第5期);99-106 *
碲处理对20CrMnTi齿轮钢中MnS夹杂物改性效果;白旭旭;《钢铁》;第54卷(第12期);35-41 *

Also Published As

Publication number Publication date
CN117089771A (en) 2023-11-21

Similar Documents

Publication Publication Date Title
CN106148844B (en) A kind of preparation method of sulfur-bearing ultralow titanium high standard bearing steel
CN109943680B (en) Production method of ultra-low carbon, low silicon, low manganese and low aluminum steel continuous casting billet
CN101519710B (en) Method for controlling non-metallic impurities in structural alloy steel
CN102199684B (en) Production method of ultralow-oxygen titanium-containing ferrite stainless steel
CN114085953B (en) Control method for acid dissolution of aluminum in aluminum-containing cold heading steel
CN111254254A (en) Preparation method of steel for sulfur-containing engineering machinery
CN114058970B (en) Production method of bearing steel
CN110331258B (en) Production process for controlling Cr content of ultra-low carbon silicon killed steel during RH vacuum treatment
CN114574770B (en) Preparation method of high-strength fatigue-resistant 60Si2MnA spring steel
CN109402327B (en) External refining production method of ultrapure high-carbon chromium bearing steel
CN109777918A (en) A kind of external refining production method refining high-carbon-chromium bearing steel inclusion particle
WO2001094648A2 (en) High-cleanliness steel and process for producing the same
CN102925811A (en) Easy-cutting vanadium-feeding high-aluminum nitriding steel and preparation method thereof
CN115404393A (en) Production method of rare earth Ce treated 16MnHIC steel blank for flange
CN117089771B (en) Magnesium tellurium composite microalloyed gear steel
CN115595402B (en) 45# steel refining and slagging method
CN109913739A (en) The production technology of the high-quality Q195 continuous casting square billet of aircraft industry fastener
US4308415A (en) Process for refining a molten metal and an apparatus therefor
US5085691A (en) Method of producing general-purpose steel
JP2000119732A (en) Melting method for high cleanliness extra-low carbon steel
CN109628696B (en) Vacuum melting process of aluminum-free low-oxygen steel
CN112063928A (en) High-hardenability and high-carburization rare earth CrMnTi gear steel and preparation method thereof
CN115261564B (en) Pure iron as non-aluminum deoxidizing material for amorphous soft magnetic thin belt and preparation method thereof
CN116574965B (en) Method for improving inclusion level of wind power steel
CN109680124A (en) A method of improving engineering machinery wear resistance castings performance

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