CN109136465A - A kind of smelting process of space flight and aviation light-high-strength stainless steel - Google Patents
A kind of smelting process of space flight and aviation light-high-strength stainless steel Download PDFInfo
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- CN109136465A CN109136465A CN201811021087.5A CN201811021087A CN109136465A CN 109136465 A CN109136465 A CN 109136465A CN 201811021087 A CN201811021087 A CN 201811021087A CN 109136465 A CN109136465 A CN 109136465A
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/068—Decarburising
- C21C7/0685—Decarburising of stainless steel
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/0006—Adding metallic additives
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/064—Dephosphorising; Desulfurising
-
- 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
- C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
-
- 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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/48—Ferrous alloys, e.g. steel alloys containing chromium with nickel with niobium or tantalum
-
- 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
- C22C38/50—Ferrous alloys, e.g. steel alloys containing chromium with nickel with titanium or zirconium
-
- 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
- C22C38/58—Ferrous alloys, e.g. steel alloys containing chromium with nickel with more than 1.5% by weight of manganese
Abstract
The present invention relates to a kind of space flight and aviation smelting process of light-high-strength stainless steel, the first furnace of the first step, place's furnace is by alloy melting, second step decarburization, quick decarburization and the oxidation for preventing chromium, third step refining, in LF refining furnace to the further decarburization of molten steel and adjusting component.This smelting mode is lower to ingredient requirement, electric furnace steel tapping reaches 2 percent or so containing C, it therefore can be using the stainless steel of cheap high-carbon FeCr and 20 percent as raw material, reduce operating cost, the production cycle of stainless steel is relatively short, flexibility is preferable, the operator needed is few, so overall cost is lower, the requirement of raw material is reduced in enterprise's production, can be using the raw material of more low in price price, and reduce staff, the consumption of personnel's wage is reduced, reduces comprehensive production cost for enterprise.
Description
Technical field
The present invention relates to a kind of smelting processes, more particularly, to a kind of smelting of light-high-strength stainless steel of space flight and aviation
Method belongs to stainless steel smelting technical field.
Background technique
Aeronautical material is the material guarantee of development and production aeronautical product, and reach aeronautical product it is intended that property
The technical foundation of energy, service life and reliability.Due to the fundamental position of aeronautical material and its to aeronautical product contribution rate
It is continuously improved, aeronautical material and aero-engine, information technology become one of three key airline companies' sky key technology arranged side by side, and to boat
Empty product develops one of six technologies having a major impact.United States Air Force is in " aeronautical technology development prediction report in 2025 " middle finger
Out, in all 43 aeronautical technologies, aeronautical material importance occupies second.In addition, aviation advanced material technology is also listed in
Big scientific and technological (respectively information technology, material technology, the sensor technology and Affordability technology) preference of U.S. national defense four
One of mesh is the material base and important component of other three technologies.High-strength aluminum alloy, high temperature alloy, surpasses titanium alloy
High strength steel, composite material, stealth material and directional solidification blade technology, directional eutectic blade technology, powder metallurgy superalloy category
Wheel disc manufacturing technology etc., the development for forth generation, the 5th generation aircraft provide material guarantee.Aviation development history proves, aviation material
Each important breakthrough of material can all promote aeronautical technology to lead to a leap the development of formula；Aeronautical material is not only aviation development
Material base and aviation development technical support.The primary structural material of aero-engine is stainless steel, high temperature conjunction
Gold and titanium alloy.On an advanced engine, the dosage of high temperature alloy and titanium alloy will account for engine general construction weight respectively
The 55%~65% and 25%~40% of amount, and more stringent requirements are proposed to many new type high temperature materials, as new type high temperature closes
Gold and high-temperature titanium alloy, high-temperature resin based composites, intermetallic compound and its composite material, heat barrier coat material, metal
Based composites, ceramic base and carbon/carbon compound material etc..In order to improve the structure efficiency of aircraft, aero-structure weight system is reduced
Number, for the stainless steel of light-high-strength with regard to extremely important, existing smelting process higher cost needs many personnel to grasp
Make, comprehensive consumption is larger, improves the overall cost of enterprise's production.
Summary of the invention
The purpose of the present invention is to overcome the above shortcomings and to provide a kind of smeltings of light-high-strength stainless steel of space flight and aviation
Method, high production efficiency and low in cost.
The object of the present invention is achieved like this:
The step of a kind of smelting process of space flight and aviation light-high-strength stainless steel, the method are as follows: the first step is just refined
Furnace, place's furnace are by alloy melting, second step decarburization, quick decarburization and the oxidation for preventing chromium, third step refining, in LF refining furnace
To the further decarburization of molten steel and adjusting component.
Further, molten steel of the refining process following compositions (weight %):
The Si 0.35%-0.45% Mn of C≤0.035% 0.7%-28%
The Ni of S≤0.007% of P≤0.050% 19.30%-19.50%
Cr 8.10%-8.40% N≤0.017%
Remaining is Fe and inevitable impurity, temperature >=1800 DEG C；It is added in refining furnace and refines, steps are as follows:
(1) lime, fluorite and aluminium powder residue adjustment are added after molten steel to refining furnace；
(2) FeNb is added after residue adjustment, FeNb recovery rate is calculated by 99.3%, and additional amount makes Nb molten steel
0.17%-0.25%；
(3) 35 minutes before coming out of the stove, 6 meter/ton of silicon-calcium wire is fed when temperature is 1600 DEG C, line feeding terminates weak stirring 5 minutes；
(4) FeTi is added, additional amount is the 0.18%-0.22% for making Nb molten steel, guarantee satisfaction (0.52Nb+Ti) >=
7C；When adding FeTi, BOTTOM ARGON BLOWING flow set 420Nl/min at charging, other side bottom blowing sets 78Nl/min；FeTi stirring is added
5-6 points of rear bottom blowings are set as weak and stir, weak to stir the time not less than 30 minutes；
(5) it comes out of the stove when the ingredient (weight %) of molten steel reaches following values,
The Si 0.50%-0.80% Mn of C≤0.05% 0.90%-1.60%
The Ni of S≤0.007% of P≤0.040% 19.02%-19.30%
Cr 8.89%-9.35% N≤0.019%, (0.52Nb+Ti) >=7C,
Remaining is that Fe and inevitable impurity, temperature >=1600 DEG C pour into slab.
Further, when adding FeNb, additional amount is to make Nb molten steel 0.18%；When FeTi is added, additional amount is to make Nb
Molten steel 0.12%.
Further, when adding FeNb, FeNb recovery rate is calculated by 99.3%, and additional amount is to make Nb molten steel 0.12%.
Further, when FeTi is added, additional amount is to make Nb molten steel 0.18%.
Further, addition FeTi stirring 5-6 divides rear bottom blowings to be set as weak and stirs, weak to stir the time not less than 30 minutes, can lead to
Mechanical stirring tooth is crossed to be stirred.
Compared with prior art, the beneficial effects obtained by the present invention are as follows being:
This smelting mode is lower to ingredient requirement, and electric furnace steel tapping reaches 2 percent or so containing C, therefore can use
The stainless steel of cheap high-carbon FeCr and 20 percent reduces operating cost, the production cycle phase of stainless steel as raw material
To shorter, flexibility is preferable, and the operator needed is few, so overall cost is lower, reduces wanting for raw material in enterprise's production
It asks, can be using the raw material of more low in price price, and reduce staff, the consumption of personnel's wage is reduced, for enterprise
Industry reduces comprehensive production cost.
Specific embodiment
A kind of the step of smelting process of space flight and aviation light-high-strength stainless steel of the present invention, the method
Are as follows:
Just furnace, place's furnace are by alloy melting, second step decarburization, quick decarburization and the oxidation for preventing chromium the to the first step
Three steps refining, in LF refining furnace to the further decarburization of molten steel and adjusting component.
Molten steel of the refining process following compositions (weight %):
The Si 0.35%-0.45% Mn of C≤0.035% 0.7%-28%
The Ni of S≤0.007% of P≤0.050% 19.30%-19.50%
Cr 8.10%-8.40% N≤0.017%
Remaining is Fe and inevitable impurity, temperature >=1800 DEG C；It is added in refining furnace and refines, steps are as follows:
(1) lime, fluorite and aluminium powder residue adjustment are added after molten steel to refining furnace；
(2) FeNb is added after residue adjustment, FeNb recovery rate is calculated by 99.3%, and additional amount makes Nb molten steel
0.17%-0.25%；
(3) 35 minutes before coming out of the stove, 6 meter/ton of silicon-calcium wire is fed when temperature is 1600 DEG C, line feeding terminates weak stirring 5 minutes；
(4) FeTi is added, additional amount is the 0.18%-0.22% for making Nb molten steel, guarantee satisfaction (0.52Nb+Ti) >=
7C；When adding FeTi, BOTTOM ARGON BLOWING flow set 420Nl/min at charging, other side bottom blowing sets 78Nl/min；FeTi stirring is added
5-6 points of rear bottom blowings are set as weak and stir, weak to stir the time not less than 30 minutes；
(5) it comes out of the stove when the ingredient (weight %) of molten steel reaches following values,
The Si 0.50%-0.80% Mn of C≤0.05% 0.90%-1.60%
The Ni of S≤0.007% of P≤0.040% 19.02%-19.30%
Cr 8.89%-9.35% N≤0.019%, (0.52Nb+Ti) >=7C,
Remaining is that Fe and inevitable impurity, temperature >=1600 DEG C pour into slab.
Preferably, when adding FeNb, additional amount is to make Nb molten steel 0.18%；When FeTi is added, additional amount is to make Nb steel
Water 0.12%.
Preferably, when adding FeNb, FeNb recovery rate is calculated by 99.3%, and additional amount is to make Nb molten steel 0.12%；It is added
When FeTi, additional amount is to make Nb molten steel 0.18%.
Preferably, addition FeTi stirring 5-6 divides rear bottom blowings to be set as weak and stirs, weak to stir the time not less than 30 minutes, can pass through
Mechanical stirring tooth is stirred.
The working principle of the invention and process for using: alloy and other items is added in furnace and is smelted first, carries out de- C, takes off
P, S processing, treated molten iron P≤0.050%S≤0.007%C≤0.035% are taken off；Then stainless steel and high charcoal ferrochrome are added
Enter in electric furnace, the molten steel after handling above-mentioned smelting furnace after fusing is added electric furnace and smelts, and the ingredient of molten steel, which reaches, to be wanted
It comes out of the stove after asking, the molten steel that electrometallurgy furnace is smelted is added to AOD furnace refining after coming out of the stove, reduction by ferrosilicon is used after the heat of oxidation, is added
Low-carbon ferrochromium and NI alloy adjusting component, come out of the stove after molten steel composition is up to standard；Finally it is adjusted according to above-mentioned LF refining step,
FeNb, hello silicon-calcium wire and Argon stirring is added to refine, molten steel composition is come out of the stove when reaching lower value: C≤0.05%Si
0.50%-0.80%Mn 0.90%-1.60%P≤0.040%S≤0.007%Ni 19.02%-19.30%Cr 8.89%-
9.35%N≤0.019%, (0.52Nb+Ti) >=7C, is finally poured, this smelting mode is lower to ingredient requirement, and circuit goes out
Steel reaches 2 percent or so containing C, therefore can use the stainless steel conduct of cheap high-carbon FeCr and 20 percent
Raw material reduces operating cost, and the production cycle of stainless steel is relatively short, and flexibility is preferable, and the operator needed is few, so
Overall cost is lower.
In addition: it should be noted that above-mentioned specific embodiment is only a prioritization scheme of this patent, the skill of this field
Any change or improvement that art personnel are done according to above-mentioned design, within the protection domain of this patent..
Claims (5)
1. a kind of space flight and aviation smelting process of light-high-strength stainless steel, which is characterized in that the step of the method are as follows:
Just furnace, place's furnace are by alloy melting, second step decarburization, quick decarburization and the oxidation for preventing chromium to one step, and third step refines,
LF refining furnace is to the further decarburization of molten steel and adjusting component.
2. a kind of smelting process of space flight and aviation light-high-strength stainless steel as described in claim 1, it is characterised in that: essence
Molten steel of the refining process following compositions (weight %):
The Si 0.35%-0.45% Mn of C≤0.035% 0.7%-28%
The Ni of S≤0.007% of P≤0.050% 19.30%-19.50%
Cr 8.10%-8.40% N≤0.017%
Remaining is Fe and inevitable impurity, temperature >=1800 DEG C；It is added in refining furnace and refines, steps are as follows:
(1) lime, fluorite and aluminium powder residue adjustment are added after molten steel to refining furnace；
(2) FeNb is added after residue adjustment, FeNb recovery rate is calculated by 99.3%, and additional amount is the 0.17%- for making Nb molten steel
0.25%；
(3) 35 minutes before coming out of the stove, 6 meter/ton of silicon-calcium wire is fed when temperature is 1600 DEG C, line feeding terminates weak stirring 5 minutes；
(4) FeTi is added, additional amount is the 0.18%-0.22% for making Nb molten steel, guarantees to meet (0.52Nb+Ti) >=7C；Add
When FeTi, BOTTOM ARGON BLOWING flow set 420Nl/min at charging, other side bottom blowing sets 78Nl/min；5-6 points of FeTi stirring is added
Bottom blowing afterwards is set as weak and stirs, weak to stir the time not less than 30 minutes；
(5) it comes out of the stove when the ingredient (weight %) of molten steel reaches following values,
The Si 0.50%-0.80% Mn of C≤0.05% 0.90%-1.60%
The Ni of S≤0.007% of P≤0.040% 19.02%-19.30%
Cr 8.89%-9.35% N≤0.019%, (0.52Nb+Ti) >=7C,
Remaining is that Fe and inevitable impurity, temperature >=1600 DEG C pour into slab.
3. a kind of smelting process of space flight and aviation light-high-strength stainless steel as described in claim 1, it is characterised in that: add
When FeNb, additional amount is to make Nb molten steel 0.18%；When FeTi is added, additional amount is to make Nb molten steel 0.12%.
4. a kind of smelting process of space flight and aviation light-high-strength stainless steel as described in claim 1, it is characterised in that: add
When FeNb, FeNb recovery rate is calculated by 99.3%, and additional amount is to make Nb molten steel 0.12%；When FeTi is added, additional amount is to make
Nb is molten steel 0.18%.
5. a kind of smelting process of space flight and aviation light-high-strength stainless steel as described in claim 1, it is characterised in that: add
Enter bottom blowings after FeTi stirring 5-6 point and be set as weak to stir, it is weak to stir the time not less than 30 minutes, it can be stirred by mechanical stirring tooth
It mixes.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811021087.5A CN109136465A (en) | 2018-09-03 | 2018-09-03 | A kind of smelting process of space flight and aviation light-high-strength stainless steel |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201811021087.5A CN109136465A (en) | 2018-09-03 | 2018-09-03 | A kind of smelting process of space flight and aviation light-high-strength stainless steel |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113502370A (en) * | 2021-06-29 | 2021-10-15 | 东北特殊钢集团股份有限公司 | Method for smelting and adding titanium in high-titanium-iron-based wrought high-temperature alloy |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101121987A (en) * | 2007-09-22 | 2008-02-13 | 山西太钢不锈钢股份有限公司 | Smelting method for titanium-containing austenitic stainless steel |
| CN104105805A (en) * | 2011-12-28 | 2014-10-15 | Posco公司 | High strength austenitic stainless steel, and preparation method thereof |
-
2018
- 2018-09-03 CN CN201811021087.5A patent/CN109136465A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101121987A (en) * | 2007-09-22 | 2008-02-13 | 山西太钢不锈钢股份有限公司 | Smelting method for titanium-containing austenitic stainless steel |
| CN104105805A (en) * | 2011-12-28 | 2014-10-15 | Posco公司 | High strength austenitic stainless steel, and preparation method thereof |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113502370A (en) * | 2021-06-29 | 2021-10-15 | 东北特殊钢集团股份有限公司 | Method for smelting and adding titanium in high-titanium-iron-based wrought high-temperature alloy |
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