CN111155030A - Marine air valve steel and preparation process thereof - Google Patents
Marine air valve steel and preparation process thereof Download PDFInfo
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- CN111155030A CN111155030A CN201911414436.4A CN201911414436A CN111155030A CN 111155030 A CN111155030 A CN 111155030A CN 201911414436 A CN201911414436 A CN 201911414436A CN 111155030 A CN111155030 A CN 111155030A
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- air valve
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B9/00—General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals
- C22B9/16—Remelting metals
- C22B9/18—Electroslag remelting
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B9/00—General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals
- C22B9/16—Remelting metals
- C22B9/20—Arc remelting
-
- 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
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/44—Ferrous alloys, e.g. steel alloys containing chromium with nickel with molybdenum or tungsten
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Physics & Mathematics (AREA)
- Plasma & Fusion (AREA)
- Heat Treatment Of Steel (AREA)
Abstract
The invention provides a marine air valve steel and a preparation process thereof, wherein the marine air valve steel comprises the following components in percentage by mass: 0.22 to 0.28 percent of C, 0.7 to 1.3 percent of Si, 0.7 to 1.3 percent of Mn, less than or equal to 0.02 percent of S, less than or equal to 0.035 percent of P, 19.1 to 19.8 percent of Crs, 9.1 to 9.8 percent of Nis, 1.8 to 2.5 percent of W, 0.05 percent of Mo0, and the balance of Fe. The invention takes Fe as a matrix, controls the mass percent of each element through component design, reduces the content of elements such as Ni, Mo and the like, realizes the reduction of components, further improves the plasticity of steel on the basis of ensuring the high-temperature corrosion resistance, the strength, the hardness and other properties of the steel, and reduces the production cost of the gas valve steel.
Description
Technical Field
The invention relates to marine air valve steel, in particular to marine air valve steel and a preparation process thereof.
Background
The air valve steel is suitable for manufacturing various valve steel, is a necessary material for manufacturing air inlet and exhaust valves of gasoline engines and diesel engines, and is a key material in the whole engines. Because the temperature is very high due to the combustion of gas in the cylinder, and impurities such as S, P in gasoline have strong corrosion resistance to materials at high temperature, the air valve steel needs to have good high-temperature corrosion resistance. With the development, the gas valve steel is gradually changed from an initial martensite type gas valve steel to an austenite type with better high-temperature performance, and the nickel-based gas valve alloy is gradually changed, but the content of Ni in the nickel-based gas valve alloy reaches more than 70%, the production cost is higher, and the application is limited. Meanwhile, the plasticity of the steel is required to be maintained and improved, so that the tensile strength, the elongation after fracture and other properties of the steel are further improved.
Disclosure of Invention
The invention aims to solve the defects in the prior art and provides marine air valve steel and a preparation process thereof.
In order to achieve the purpose, the invention adopts the following technical scheme:
the marine air valve steel comprises the following components in percentage by mass: 0.22 to 0.28 percent of C, 0.7 to 1.3 percent of Si, 0.7 to 1.3 percent of Mn, less than or equal to 0.02 percent of S, less than or equal to 0.035 percent of P, 19.1 to 19.8 percent of Crs, 9.1 to 9.8 percent of Nis, 1.8 to 2.5 percent of W, 0.05 percent of Mo0, and the balance of Fe.
Preferably, the composition comprises the following components in percentage by mass: 0.22% of C, 0.7% of Si, 0.7% of Mn0.02% of S, 0.035% of P, 19.1% of Cr19.1%, 9.1% of Ni9%, 1.8% of W, 0.05% of Mo0.05% and the balance of Fe.
Preferably, the composition comprises the following components in percentage by mass: 0.26% of C, 0.9% of Si, 0.9% of Mn0.9% of S, 0.01% of P, 19.4% of Cr19.4%, 9.4% of Ni9.3% of W, 0.05% of Mo0.05% of the balance of Fe.
Preferably, the composition comprises the following components in percentage by mass: 0.28% of C, 1.3% of Si, 1.3% of Mn1, 0.01% of S, 0.035% of P, 19.8% of Cr19, 9.8% of Ni9, 2.5% of W, 0.05% of Mo0, and the balance of Fe.
Preferably, the macrostructures of the air valve steel are all less than or equal to grade 2, the nonmetallic inclusions are all less than or equal to grade 1.5, and the grain size is all finer than grade 6.
Preferably, each index of the air valve steel is Rm: 700-850MPa, Rp0.2-350 MPa, A-26 and Z-45.
A preparation process of the marine air valve steel comprises the following steps:
step 1, raw material preparation, wherein all materials, casting refractory materials, deoxidizing agents and the like are strictly baked to ensure that the materials are free of oil and impurities;
step 2, intermediate frequency smelting, namely putting the raw materials into an intermediate frequency furnace, adding rare earth La-Ce according to the proportion of 0.4%, blowing argon in a tundish, and pouring an electrode;
step 3, electroslag, namely adopting a slag system CaF: al (Al)2O3And (5) keeping arc striking at a rate of 70:30, and controlling current to be 1000-1500A. An electroslag furnace with good equipment is adopted for production;
step 4, forging, wherein the forging heating temperature is 1120-;
step 5, hot rolling, wherein the heating temperature is 1120-1170 ℃;
step 6, solid solution is carried out, wherein the solid solution temperature is 980 and 1050 ℃, and water cooling is carried out;
and 7, inspecting the finished product, packaging and warehousing.
Preferably, the forging ratio in step 3 is controlled to be 4 or more.
Preferably, in the intermediate frequency smelting in the step 2, a double vacuum smelting technology of a vacuum induction smelting technology and a vacuum arc remelting technology can be adopted.
When the steel material composition is designed, the content of C is 0.22-0.28%, the range of low carbon is controlled, the steel material is strengthened, and the reduction of the weldability of the steel material is avoided;
the content of Si is controlled to be 0.7-1.3%, the proper increase is obtained, the improvement of the elastic limit, the yield point and the tensile strength of the steel is facilitated, and because most of Si can be dissolved in ferrite, the strength and the hardness of the ferrite are improved, and the welding performance of the steel can be reduced when the content of Si exceeds 1.3%; meanwhile, Si is oxidized at high temperature to produce a compact SiO2 film, so that oxygen can be prevented from permeating, and the oxidation speed of the alloy is reduced; si is combined with elements such as Cr, W and the like, so that the corrosion resistance and the oxidation resistance can be obviously improved, and the use of steel in the high-temperature environment of the air valve is facilitated.
Cr can obviously improve the strength, hardness and wear resistance of steel, is a key element of high-temperature oxidation resistance and corrosion resistance, but can reduce the plasticity and toughness, while Ni can improve the strength of steel and keep good plasticity and toughness, the invention controls the mass percent of Ni to be 9.1-9.8%, and forms solid solution with Cr at high temperature, so that the steel has higher high-temperature strength, and simultaneously, the Cr element which is easy to dissolve in ferrite is matched, so that the steel can improve the plasticity of the steel at normal temperature while ensuring the hardness, strength and wear resistance of the steel.
The W element and the Mo element are used for forming alloy carbide with the C element, so that the wear resistance of steel is improved, and the steel is more suitable for the working environment of the air valve.
The invention takes Fe as a matrix, controls the mass percent of each element through composition design and process improvement, reduces the content of elements such as Ni, Mo and the like, realizes the reduction of the compositions, further improves the plasticity of the steel on the basis of ensuring the high-temperature corrosion resistance, the strength, the hardness and other properties of the steel, and reduces the production cost of the gas valve steel.
Detailed Description
In order to further understand the objects, structures, features and functions of the present invention, the following embodiments are described in detail.
Example 1
The marine air valve steel comprises the following components in percentage by mass: 0.22% of C, 0.7% of Si, 0.7% of Mn0.02% of S, 0.035% of P, 19.1% of Cr19.1%, 9.1% of Ni9%, 1.8% of W, 0.05% of Mo0.05% and the balance of Fe.
Example 2
The marine air valve steel comprises the following components in percentage by mass: 0.26% of C, 0.9% of Si, 0.9% of Mn0.9% of S, 0.01% of P, 19.4% of Cr19.4%, 9.4% of Ni9.3% of W, 0.05% of Mo0.05% of the balance of Fe.
Example 3
The marine air valve steel comprises the following components in percentage by mass: 0.28% of C, 1.3% of Si, 1.3% of Mn1, 0.01% of S, 0.035% of P, 19.8% of Cr19, 9.8% of Ni9, 2.5% of W, 0.05% of Mo0, and the balance of Fe.
Preferably, the macrostructures of the air valve steel are all less than or equal to grade 2, the nonmetallic inclusions are all less than or equal to grade 1.5, and the grain size is all finer than grade 6.
Preferably, each index of the air valve steel is Rm: 700-850MPa, Rp0.2-350 MPa, A-26 and Z-45.
The content of C is 0.22-0.28%, the range of low carbon is controlled, and the weldability of the steel is prevented from being reduced while the steel is strengthened;
the content of Si is controlled to be 0.7-1.3%, the proper increase is obtained, the improvement of the elastic limit, the yield point and the tensile strength of the steel is facilitated, and because most of Si can be dissolved in ferrite, the strength and the hardness of the ferrite are improved, and the welding performance of the steel can be reduced when the content of Si exceeds 1.3%; meanwhile, Si is oxidized at high temperature to produce a compact SiO2 film, so that oxygen can be prevented from permeating, and the oxidation speed of the alloy is reduced; si is combined with elements such as Cr, W and the like, so that the corrosion resistance and the oxidation resistance can be obviously improved, and the use of steel in the high-temperature environment of the air valve is facilitated.
Cr can obviously improve the strength, hardness and wear resistance of steel, is a key element of high-temperature oxidation resistance and corrosion resistance, but can reduce the plasticity and toughness, while Ni can improve the strength of steel and keep good plasticity and toughness, the invention controls the mass percent of Ni to be 9.1-9.8%, and forms solid solution with Cr at high temperature, so that the steel has higher high-temperature strength, and simultaneously, the Cr element which is easy to dissolve in ferrite is matched, so that the steel can improve the plasticity of the steel at normal temperature while ensuring the hardness, strength and wear resistance of the steel.
The W element and the Mo element are used for forming alloy carbide with the C element, so that the wear resistance of steel is improved, and the steel is more suitable for the working environment of the air valve.
A preparation process of the marine air valve steel comprises the following steps:
step 1, raw material preparation, wherein all materials, casting refractory materials, deoxidizing agents and the like are strictly baked to ensure that the materials are free of oil and impurities;
step 2, intermediate frequency smelting, namely putting the raw materials into an intermediate frequency furnace, adding rare earth La-Ce according to the proportion of 0.4%, blowing argon in a tundish, and pouring an electrode;
step 3, electroslag, namely adopting a slag system CaF: al (Al)2O3And (5) keeping arc striking at a rate of 70:30, and controlling current to be 1000-1500A. An electroslag furnace with good equipment is adopted for production;
step 4, forging, wherein the forging heating temperature is 1120-;
step 5, hot rolling, wherein the heating temperature is 1120-1170 ℃;
step 6, solid solution is carried out, wherein the solid solution temperature is 980 and 1050 ℃, and water cooling is carried out;
and 7, inspecting the finished product, packaging and warehousing.
Preferably, the forging ratio in step 3 is controlled to be 4 or more.
Preferably, in the step 2, a double vacuum smelting technology of a vacuum induction smelting technology and a vacuum arc remelting technology can be adopted in the intermediate frequency smelting, so that the content of harmful elements and inclusions in the steel is better controlled. The Vacuum Induction Melting (VIM) technology utilizes the eddy current generated in the electromagnetic induction process to melt metal under vacuum condition to achieve the purpose of melting metal. This technique can be used to refine high purity metals and alloys due to its high sealing properties. Vacuum Arc Remelting (VAR) is a technique that under vacuum conditions, an arc is used as a heat source to rapidly melt a metal electrode under the action of high temperature, and the metal electrode is solidified again in a condenser, so that the aims of purifying the metal and improving the structure of the metal electrode are fulfilled.
The performance test result of the marine air valve steel at 20 ℃ is as follows:
according to the invention, Fe is used as a matrix, the mass percent of each element is controlled through component design, the content of elements such as Ni, Mo and the like is reduced, the reduction of components is realized, the plasticity of steel is further improved on the basis of ensuring the high-temperature corrosion resistance, the strength, the hardness and other properties of the steel, and the production cost of the gas valve steel is reduced.
The present invention has been described in relation to the above embodiments, which are only exemplary of the implementation of the present invention. It should be noted that the disclosed embodiments do not limit the scope of the invention. Rather, it is intended that all such modifications and variations be included within the spirit and scope of this invention.
Claims (9)
1. The marine air valve steel is characterized by comprising the following components in percentage by mass: 0.22 to 0.28 percent of C, 0.7 to 1.3 percent of Si, 0.7 to 1.3 percent of Mn, less than or equal to 0.02 percent of S, less than or equal to 0.035 percent of P, 19.1 to 19.8 percent of Crs, 9.1 to 9.8 percent of Nis, 1.8 to 2.5 percent of W, 0.05 percent of Mo0, and the balance of Fe.
2. The marine air valve steel as claimed in claim 1, which comprises the following components in percentage by mass: 0.22% of C, 0.7% of Si, 0.7% of Mn0.02% of S, 0.035% of P, 19.1% of Cr19.1%, 9.1% of Ni9%, 1.8% of W, 0.05% of Mo0.05% and the balance of Fe.
3. The marine air valve steel as claimed in claim 1, which comprises the following components in percentage by mass: 0.26% of C, 0.9% of Si, 0.9% of Mn0.9% of S, 0.01% of P, 19.4% of Cr19.4%, 9.4% of Ni9.3% of W, 0.05% of Mo0.05% of the balance of Fe.
4. The marine air valve steel as claimed in claim 1, which comprises the following components in percentage by mass: 0.28% of C, 1.3% of Si, 1.3% of Mn1, 0.01% of S, 0.035% of P, 19.8% of Cr19, 9.8% of Ni9, 2.5% of W, 0.05% of Mo0, and the balance of Fe.
5. The marine air valve steel according to claim 1, wherein the macrostructures of the air valve steel are all less than or equal to grade 2, the non-metallic inclusions are all less than or equal to grade 1.5, and the grain size is all finer than grade 6.
6. The marine air valve steel according to claim 1, wherein each index of the air valve steel is Rm: 700-850MPa, Rp0.2-350 MPa, A-26 and Z-45.
7. Process for the preparation of a marine air valve steel according to any one of claims 1 to 6, characterized by comprising the following steps:
step 1, raw material preparation, wherein all materials, casting refractory materials, deoxidizing agents and the like are strictly baked to ensure that the materials are free of oil and impurities;
step 2, intermediate frequency smelting, namely putting the raw materials into an intermediate frequency furnace, adding rare earth La-Ce according to the proportion of 0.4%, blowing argon in a tundish, and pouring an electrode;
step 3, electroslag, namely adopting a slag system CaF: al (Al)2O3=70:30, the arc striking is stable, the current is controlled between 1000A-1500A,
an electroslag furnace with good equipment is adopted for production;
step 4, forging, wherein the forging heating temperature is 1120-;
step 5, hot rolling, wherein the heating temperature is 1120-1170 ℃;
step 6, solid solution is carried out, wherein the solid solution temperature is 980 and 1050 ℃, and water cooling is carried out;
and 7, inspecting the finished product, packaging and warehousing.
8. The process for preparing the marine air valve steel according to claim 7, wherein: the forging ratio in step 3 is controlled to be 4 or more.
9. The process for preparing the marine air valve steel according to claim 7, wherein: in the step 2, a double vacuum smelting technology of a vacuum induction smelting technology and a vacuum arc remelting technology can be adopted in the intermediate frequency smelting.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911414436.4A CN111155030A (en) | 2019-12-31 | 2019-12-31 | Marine air valve steel and preparation process thereof |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911414436.4A CN111155030A (en) | 2019-12-31 | 2019-12-31 | Marine air valve steel and preparation process thereof |
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| Publication Number | Publication Date |
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| CN111155030A true CN111155030A (en) | 2020-05-15 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201911414436.4A Pending CN111155030A (en) | 2019-12-31 | 2019-12-31 | Marine air valve steel and preparation process thereof |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116254457A (en) * | 2021-12-09 | 2023-06-13 | 江苏新华合金有限公司 | Bar for air valve steel and manufacturing process thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1154419A (en) * | 1996-10-14 | 1997-07-16 | 冶金工业部钢铁研究总院 | ultra hypoeutectoid, diphasic stainless steel, and prodn. method thereof |
| CN102395696A (en) * | 2009-04-20 | 2012-03-28 | 日立金属株式会社 | Heat resistant steel for use in engine valve having excellent high-temperature strength |
| CN103397276A (en) * | 2013-08-12 | 2013-11-20 | 钢铁研究总院 | High-strength nickel-saving air valve steel and preparation method thereof |
| KR20140047451A (en) * | 2012-10-12 | 2014-04-22 | 현대중공업 주식회사 | A method of manufacturing an exhaust valve spindle for a ship engine |
-
2019
- 2019-12-31 CN CN201911414436.4A patent/CN111155030A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1154419A (en) * | 1996-10-14 | 1997-07-16 | 冶金工业部钢铁研究总院 | ultra hypoeutectoid, diphasic stainless steel, and prodn. method thereof |
| CN102395696A (en) * | 2009-04-20 | 2012-03-28 | 日立金属株式会社 | Heat resistant steel for use in engine valve having excellent high-temperature strength |
| KR20140047451A (en) * | 2012-10-12 | 2014-04-22 | 현대중공업 주식회사 | A method of manufacturing an exhaust valve spindle for a ship engine |
| CN103397276A (en) * | 2013-08-12 | 2013-11-20 | 钢铁研究总院 | High-strength nickel-saving air valve steel and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 徐朋: "热加工工艺对3Cr20Ni10W2气阀钢组织的影响", 《物理测试》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116254457A (en) * | 2021-12-09 | 2023-06-13 | 江苏新华合金有限公司 | Bar for air valve steel and manufacturing process thereof |
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Application publication date: 20200515 |