CN114318104A - Heat-resistant steel material for variable-section nozzle ring of gasoline engine - Google Patents
Heat-resistant steel material for variable-section nozzle ring of gasoline engine Download PDFInfo
- Publication number
- CN114318104A CN114318104A CN202111486237.1A CN202111486237A CN114318104A CN 114318104 A CN114318104 A CN 114318104A CN 202111486237 A CN202111486237 A CN 202111486237A CN 114318104 A CN114318104 A CN 114318104A
- Authority
- CN
- China
- Prior art keywords
- heat
- resistant steel
- percent
- steel material
- gasoline engine
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Supercharger (AREA)
Abstract
The invention provides a heat-resistant steel material for a variable-section nozzle ring of a gasoline engine, which comprises the following components in percentage by weight: nickel: 23% -27%, chromium: 25% -30%, carbon: 0.3% -0.6%, silicon: 1.8% -2.5%, manganese: 1.5% -2.5%; sulfur: 0 to 0.03 percent; phosphorus: 0 to 0.03 percent; molybdenum: 1.5% -2.5%; niobium: 1.0% -1.75%; tungsten: 1.5% -2.8%, and the balance of iron; the molybdenum is added to replace a part of tungsten, the production cost is greatly reduced by adding the molybdenum element, and the high-temperature service life of the heat-resistant steel material is maintained to the maximum extent by controlling the chromium content in the heat-resistant steel material to be 30%. The application provides a can be used to heat-resisting steel material of variable cross section nozzle circle of gasoline engine, has the high temperature strength, the required durability wearability and high temperature creep performance of bearing the high temperature operating mode about 1080 ℃, high temperature oxidation resistance, advantages such as low in production cost.
Description
Technical Field
The disclosure relates to the technical field of heat-resistant steel, in particular to a heat-resistant steel material for a variable-section nozzle ring of a gasoline engine.
Background
The turbocharger increases air inflow by compressing air, and pushes the air in the turbine chamber by using the inertia impulse force of the exhaust gas discharged by the engine, the turbine drives a coaxial impeller, and the impeller pumps the air sent by the air filtering pipeline to pressurize the air to enter the cylinder. With the improvement of the use requirements, the performance requirements on the aspects of high temperature resistance, corrosion resistance and the like of the turbocharger are higher and higher.
Some technical solutions related to heat resistant steel have been disclosed in the prior art, for example, the publication numbers are: the invention patent of CN112853207A discloses a heat-resistant steel material for a variable-section nozzle ring of a gasoline engine and a smelting method thereof, and particularly discloses that the heat-resistant steel comprises the following chemical components in percentage by weight: c: 0.7% -1.3%, Si: 0.5% -2%, Mn: 0-1.5%, Cr: 32-40%, Ni: 11% -18%, Mo: 1.5% -4%, W: 0.2% -1.5%, S: 0-0.035%, P: 0-0.035%, and the balance of Fe; the metallographic structure of the heat-resistant steel is that M is uniformly distributed in an austenite matrix23C6The hard points of the carbon compounds of MoW and W are 2-7 grades in grain size, and the heat-resistant steel provided by the technical scheme is suitable for high temperature of more than 950 ℃ in a working environment and has oxidation resistance at high temperature.
For example, the publication number is: CN110952036A patent discloses a free-cutting heat-resistant steel for manufacturing a turbocharger exhaust valve assembly, which is composed of the following element components by mass fraction: carbon: 0.25% -0.5%, silicon: 0.5% -2.0%, manganese: 0-2%, phosphorus: 0-0.035%, sulfur: 0.1% -0.4%, nickel: 24% -27%, chromium: 24% -27%, tungsten: 2.5% -3.5%, niobium: 0.5% -2.0%, vanadium: 0.5 to 2.0 percent of iron and the balance of iron. The free-cutting heat-resistant steel provided by the technical scheme can work under the working condition of 1000 ℃, the content of added tungsten is high, the cost of tungsten is high, the processing cost of the heat-resistant steel material is higher, the content of sulfur in the heat-resistant steel material is high, and the content of sulfur as impurities is high, so that the corrosion resistance, the high-temperature oxidation resistance and the mechanical property of the heat-resistant steel material are reduced.
From the content disclosed in the prior art, the common heat-resistant steel material actually used at present can only work under the working condition of 1000 ℃, has high production cost, can not meet the working condition requirement of higher temperature, has poor high-temperature resistance, and still has the problem of inconvenient use.
Disclosure of Invention
The heat-resistant steel material for the variable-section nozzle ring of the gasoline engine has the advantages of high temperature strength, durability, wear resistance, high temperature creep performance, high temperature oxidation resistance, low production cost and the like, which are required by bearing high-temperature working conditions of about 1080 ℃.
One of the concepts of the present disclosure is to provide a heat resistant steel material for a variable cross-section nozzle ring of a gasoline engine, wherein the heat resistant steel comprises the following chemical components by weight percent: nickel: 23% -27%, chromium: 25% -30%, carbon: 0.3% -0.6%, silicon: 1.8% -2.5%, manganese: 1.5% -2.5%; sulfur: 0 to 0.03 percent; phosphorus: 0 to 0.03 percent; molybdenum: 1.5% -2.5%; niobium: 1.0% -1.75%; tungsten: 1.5% -2.8%, and the balance of iron.
Further, another concept of the present disclosure is that the heat resistant steel includes the following components: nickel: 23% -27%, chromium: 28% -30%, carbon: 0.3% -0.5%, silicon: 2.1% -2.5%, manganese: 1.5% -2.0%; sulfur: 0 to 0.03 percent; phosphorus: 0 to 0.03 percent; molybdenum: 1.5% -2.5%; niobium: 1.0% -1.75%; tungsten: 1.5% -2.4%, and the balance of iron.
Still further, another concept of the present disclosure is that the heat resistant steel includes the following components: nickel: 23% -27%, chromium: 28% -30%, carbon: 0.3% -0.5%, silicon: 2.3% -2.5%, manganese: 1.5% -1.8%; sulfur: 0 to 0.03 percent; phosphorus: 0 to 0.03 percent; molybdenum: 1.5% -2.5%; niobium: 1.0% -1.75%; tungsten: 1.5% -2.0%, and the balance of iron.
In the technical scheme, the stability of the heat-resistant steel material protective film is improved by adding a proper amount of nickel, and the brittleness of the heat-resistant steel material is improved; the strength of the material is improved by adding a proper amount of carbon; by adding a proper amount of silicon and manganese for deoxidation, the pore defects of the heat-resistant steel material are reduced, the high-temperature oxidation resistance of the material can be improved, and carbon can form eutectic carbide with elements such as niobium, tungsten, molybdenum and the like, so that the wear resistance of the heat-resistant steel material is greatly improved; the high-temperature strength, the high-temperature durability and the creep property of the heat-resistant steel material can be improved by adding a proper amount of molybdenum and tungsten, the oxidation resistance and the corrosion resistance of the heat-resistant steel material are improved, the overall high-temperature resistance level of the heat-resistant steel material can be further improved by adding a proper amount of tungsten, the high-temperature stability of the material is improved, and the corrosion resistance of a passive film on the surface layer of the material in a special environment can be promoted by molybdenum; by adding a proper amount of niobium which is a stabilizing element capable of forming carbon and nitrogen compounds, the niobium can be used for preventing chromium and carbon in the heat-resistant steel from being combined to form chromium carbide, the corrosion resistance is reduced due to the reduction of chromium concentration, the high-temperature oxidation resistance of the heat-resistant steel material is improved, and the formed niobium carbide compound can also refine grains, strengthen grain boundaries and improve the mechanical property of the heat-resistant steel material.
Still further, another concept of the present disclosure is that, in the heat-resistant steel composition, the content of chromium is 30%, and the heat-resistant steel material utilizes chromium to improve the high-temperature oxidation resistance and the high-temperature strength of the heat-resistant steel material, but too much chromium may cause more brittle phase carbides to appear and reduce the material performance, and in the technical scheme, the content of chromium is controlled between 25% and 30%, and preferably the content of chromium is 30%, so as to maintain the high-temperature life of the heat-resistant steel material.
Further, the high-temperature tensile properties of the heat-resistant steel at 1000 ℃ are respectively as follows: the tensile strength is more than 120MPa, the yield strength is more than 85MPa, the elongation is less than 49 percent, and the reduction of area is less than 55 percent. The heat-resistant steel provided by the technical scheme has high-temperature strength and durability and wear resistance required for bearing high-temperature working conditions of about 1000 ℃.
Further, the high-temperature tensile properties of the heat-resistant steel at 1050 ℃ are respectively as follows: the tensile strength is more than 91MPa, the yield strength is more than 64MPa, the elongation is less than 60 percent, and the reduction of area is less than 65 percent. The heat-resistant steel provided by the technical scheme has high-temperature strength and durability and wear resistance required for bearing high-temperature working conditions of about 1050 ℃.
According to the heat-resistant steel material for the variable-section nozzle ring of the gasoline engine, a proper amount of molybdenum element is added, so that the high-temperature strength, the high-temperature durability and the creep property of the heat-resistant steel material are improved, meanwhile, the oxidation resistance and the corrosion resistance of the heat-resistant steel material can be improved, the molybdenum and the tungsten have similar effects, a part of tungsten can be replaced by adding molybdenum in the technical scheme, the cost of tungsten is higher, the production cost is greatly reduced by adding the molybdenum element, and the high-temperature service life of the heat-resistant steel material is maintained to the maximum extent by controlling the chromium content in the heat-resistant steel material to be 30%; on the other hand, phosphorus as an impurity can reduce the corrosion resistance, the high-temperature oxidation resistance and the mechanical property of the heat-resistant steel material, and the content of phosphorus in the heat-resistant steel material provided by the technical scheme is less than 0.03% under the condition of not increasing the production cost, so that the heat-resistant steel material has better high-temperature resistance.
The heat-resistant steel material disclosed by the prior art can only bear the high-temperature working condition of about 1000 ℃ at most, and when the temperature reaches 1000 ℃, the high-temperature performance of the heat-resistant steel material is greatly influenced by small temperature changes.
The application provides a can be used to heat-resisting steel material of variable cross-section nozzle circle of gasoline engine, has the high temperature strength, the durability wearability and the high temperature creep property that bear the high temperature operating mode required more than 1000 ℃, high temperature oxidation resistance, low in production cost etc. advantage.
Detailed Description
In order to make the objects, technical solutions and advantages of the present disclosure more apparent, the present disclosure is further described in detail below with reference to the embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the disclosure and are not intended to limit the disclosure.
Example 1
The embodiment provides a heat-resistant steel material for a variable-section nozzle ring of a gasoline engine, and the chemical components of the heat-resistant steel (embodiment 1) are as follows in percentage by weight: nickel: 25.2%, chromium: 28.1%, carbon: 0.48%, silicon: 2.3%, manganese: 2.2 percent; sulfur: 0.02 percent; phosphorus: 0.02 percent; molybdenum: 2.0 percent; niobium: 1.35 percent; tungsten: 2.3%, and the balance iron.
The high temperature resistance of the heat-resistant steel provided above (example 1) at different temperatures is shown in tables 1, 2, and 3 below, respectively:
TABLE 1 high temperature tensile Properties
TABLE 2 creep rupture
| Test temperature C | Stress Mpa | Duration h | Second stage creep rate S-1 | Remarks for note |
| 900 | 105 | 61.3 | 3.78x10-7 | / |
| 1000 | 50 | 200 | 4.82x10-8 | Is not broken |
| 1050 | 25 | 200 | 5.13x10-8 | Is not broken |
| 1080 | 25 | 200 | 5.66x10-8 | Is not broken |
TABLE 3 thermal diffusivity
| Test temperature C | Coefficient of thermal diffusion (mm)2/s) |
| 900 | 4.02 |
| 1000 | 4.18 |
| 1050 | 4.35 |
| 1080 | 4.47 |
Example 2
The embodiment provides a heat-resistant steel material for a variable-section nozzle ring of a gasoline engine, and the chemical components of the heat-resistant steel (embodiment 2) are as follows by weight percent: nickel: 23.8%, chromium: 25.6%, carbon: 0.39%, silicon: 1.92%, manganese: 1.67 percent; sulfur: 0.02 percent; phosphorus: 0.02 percent; molybdenum: 1.66 percent; niobium: 1.18 percent; tungsten: 1.73%, and the balance iron.
The high temperature resistance of the heat-resistant steel provided above (example 2) at different temperatures is shown in tables 4, 5, and 6 below, respectively:
TABLE 4 high temperature tensile Properties
TABLE 5 creep endurance
| Test temperature C | Stress Mpa | Duration h | Second stage creep rate S-1 | Remarks for note |
| 900 | 105 | 60.5 | 3.92x10-7 | / |
| 1000 | 50 | 200 | 50.3x10-8 | Is not broken |
| 1050 | 25 | 200 | 5.39x10-8 | Is not broken |
| 1080 | 25 | 200 | 5.72x10-8 | Is not broken |
TABLE 6 thermal diffusivity
| Test temperature C | Coefficient of thermal diffusion (mm)2/s) |
| 900 | 4.43 |
| 1000 | 4.49 |
| 1050 | 4.62 |
| 1080 | 4.78 |
Example 3
The embodiment provides a heat-resistant steel material for a variable-section nozzle ring of a gasoline engine, and the chemical components of the heat-resistant steel (embodiment 3) are as follows by weight percent: nickel: 26.5%, chromium: 29.2%, carbon: 0.55%, silicon: 2.41%, manganese: 2.47 percent; sulfur: 0.02 percent; phosphorus: 0.02 percent; molybdenum: 2.40 percent; niobium: 1.66 percent; tungsten: 2.76%, and the balance iron.
The high temperature resistance of the heat-resistant steel provided above (example 3) at different temperatures is shown in tables 7, 8, and 9 below, respectively:
TABLE 7 high temperature tensile Properties
TABLE 8 creep rupture
TABLE 9 thermal diffusivity
| Test temperature C | Coefficient of thermal diffusion (mm)2/s) |
| 900 | 4.05 |
| 1000 | 4.11 |
| 1050 | 4.29 |
| 1080 | 4.38 |
Comparative example 1
The embodiment provides a heat-resistant steel material for a variable-section nozzle ring of a gasoline engine, and the chemical components of the heat-resistant steel (comparative example 1) are as follows in percentage by weight: nickel: 25.1%, chromium: 25.4%, carbon: 0.41%, silicon: 1.25%, manganese: 0.4 percent; sulfur: 0.13 percent; phosphorus: 0.03 percent; niobium: 1.1 percent; tungsten: 3.1 percent; vanadium: 1.2%, and the balance iron.
The high temperature resistance at 1000 ℃ of the heat-resistant steel provided above (comparative example 1) and the heat-resistant steel provided in examples is shown in table 10 below:
TABLE 10 high temperature tensile Properties
As can be seen from Table 10, the heat-resistant steel material provided in comparative example 1 has far lower heat-resistant high-temperature performance at 1000 ℃ than the heat-resistant steel materials provided in examples 1 to 3.
Comparative example 2
The embodiment provides a heat-resistant steel material for a variable-section nozzle ring of a gasoline engine, and the chemical components of the heat-resistant steel (comparative example 2) are as follows in percentage by weight: nickel: 36.3%, chromium: 18.50%, carbon: 0.34%, silicon: 1.10%, manganese: 0.86 percent; sulfur: 0.006%; phosphorus: 0.028%; molybdenum: 0.013%; niobium: 1.28 percent; tungsten: 0.037%; vanadium: 0.074%; nitrogen: 0.059%, and the balance iron.
The high temperature resistance at 1050 ℃ of the heat-resistant steel provided above (comparative example 2) and the heat-resistant steel provided in examples is shown in table 11 below:
TABLE 11 high temperature tensile Properties
As can be seen from Table 11, the heat-resistant steel material provided in comparative example 2 is far inferior in heat-resistant high-temperature performance at 1050 ℃ to the heat-resistant steel materials provided in examples 1 to 3.
The present disclosure has been described in detail above, and the principles and embodiments of the present disclosure have been explained herein using specific examples, which are provided only to assist understanding of the present disclosure and the core concepts. It should be noted that, for those skilled in the art, it is possible to make several improvements and modifications to the present disclosure without departing from the principle of the present disclosure, and such improvements and modifications also fall within the scope of the claims of the present disclosure.
Claims (6)
1. The heat-resistant steel material for the variable-section nozzle ring of the gasoline engine is characterized by comprising the following components in percentage by weight: nickel: 23% -27%, chromium: 25% -30%, carbon: 0.3% -0.6%, silicon: 1.8% -2.5%, manganese: 1.5% -2.5%; sulfur: 0 to 0.03 percent; phosphorus: 0 to 0.03 percent; molybdenum: 1.5% -2.5%; niobium: 1.0% -1.75%; tungsten: 1.5% -2.8%, and the balance of iron.
2. The steel of claim 1, wherein the heat resistant steel comprises, in weight percent: nickel: 23% -27%, chromium: 25% -30%, carbon: 0.3% -0.5%, silicon: 2.1% -2.5%, manganese: 1.5% -2.0%; sulfur: 0 to 0.03 percent; phosphorus: 0 to 0.03 percent; molybdenum: 1.5% -2.5%; niobium: 1.0% -1.75%; tungsten: 1.5% -2.4%, and the balance of iron.
3. The heat-resistant steel material for the variable-section nozzle ring of the gasoline engine as claimed in claim 2, wherein the heat-resistant steel material comprises the following components in percentage by weight: nickel: 23% -27%, chromium: 28% -30%, carbon: 0.3% -0.5%, silicon: 2.3% -2.5%, manganese: 1.5% -1.8%; sulfur: 0 to 0.03 percent; phosphorus: 0 to 0.03 percent; molybdenum: 1.5% -2.5%; niobium: 1.0% -1.75%; tungsten: 1.5% -2.0%, and the balance of iron.
4. The heat-resistant steel material for the variable-section nozzle ring of the gasoline engine as claimed in claim 3, wherein the chromium content in the composition of the heat-resistant steel is 30%.
5. The heat-resistant steel material for the variable-section nozzle ring of the gasoline engine as claimed in claim 1, wherein the high-temperature tensile properties of the heat-resistant steel at 1000 ℃ are respectively as follows: the tensile strength is more than 120MPa, the yield strength is more than 85MPa, the elongation is less than 49 percent, and the reduction of area is less than 55 percent.
6. The heat-resistant steel material for the variable-section nozzle ring of the gasoline engine as claimed in claim 1, wherein the high-temperature tensile properties of the heat-resistant steel at 1050 ℃ are respectively as follows: the tensile strength is more than 91MPa, the yield strength is more than 64MPa, the elongation is less than 60 percent, and the reduction of area is less than 65 percent.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111486237.1A CN114318104A (en) | 2021-12-07 | 2021-12-07 | Heat-resistant steel material for variable-section nozzle ring of gasoline engine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111486237.1A CN114318104A (en) | 2021-12-07 | 2021-12-07 | Heat-resistant steel material for variable-section nozzle ring of gasoline engine |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114318104A true CN114318104A (en) | 2022-04-12 |
Family
ID=81048179
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111486237.1A Pending CN114318104A (en) | 2021-12-07 | 2021-12-07 | Heat-resistant steel material for variable-section nozzle ring of gasoline engine |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114318104A (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6431931A (en) * | 1987-07-29 | 1989-02-02 | Nidatsuku Kk | Production of curved tube made of heat-resistant centrifugal cast alloy |
| CN1340109A (en) * | 1999-02-16 | 2002-03-13 | 桑德维克公司 | Heat resistant austenitic stainless steel |
| CN1942598A (en) * | 2004-04-19 | 2007-04-04 | 日立金属株式会社 | High-cr high-ni austenitic heat-resistant cast steel and exhaust system component produced from same |
| CN103572178A (en) * | 2012-08-07 | 2014-02-12 | 上海世传金属材料研发中心 | High-temperature-resistant steel and production method thereof |
| CN104164625A (en) * | 2014-08-01 | 2014-11-26 | 中材装备集团有限公司 | Chlorine-corrosion-resistant heat-resistant steel for high-temperature working conditions and application method thereof |
| CN106399800A (en) * | 2016-09-18 | 2017-02-15 | 中国华能集团公司 | Austenite heat-resisting steel and heat treatment technology thereof |
-
2021
- 2021-12-07 CN CN202111486237.1A patent/CN114318104A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6431931A (en) * | 1987-07-29 | 1989-02-02 | Nidatsuku Kk | Production of curved tube made of heat-resistant centrifugal cast alloy |
| CN1340109A (en) * | 1999-02-16 | 2002-03-13 | 桑德维克公司 | Heat resistant austenitic stainless steel |
| CN1942598A (en) * | 2004-04-19 | 2007-04-04 | 日立金属株式会社 | High-cr high-ni austenitic heat-resistant cast steel and exhaust system component produced from same |
| CN103572178A (en) * | 2012-08-07 | 2014-02-12 | 上海世传金属材料研发中心 | High-temperature-resistant steel and production method thereof |
| CN104164625A (en) * | 2014-08-01 | 2014-11-26 | 中材装备集团有限公司 | Chlorine-corrosion-resistant heat-resistant steel for high-temperature working conditions and application method thereof |
| CN106399800A (en) * | 2016-09-18 | 2017-02-15 | 中国华能集团公司 | Austenite heat-resisting steel and heat treatment technology thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP2113581B1 (en) | Heat and corrosion resistant cast stainless steels with improved high temperature strength and ductility | |
| EP2765214B1 (en) | Stainless steel alloys, turbocharger turbine housings formed from the stainless steel alloys, and methods for manufacturing the same | |
| JP5100487B2 (en) | Manufacturing method of sintered machine parts | |
| KR101809853B1 (en) | Austenitic steel excellent in high temperature strength | |
| JP2002226955A (en) | Turbo-parts for turbo-charger and production method therefor | |
| JP2542753B2 (en) | Austenitic heat-resistant cast steel exhaust system parts with excellent high-temperature strength | |
| JPH0826438B2 (en) | Ferritic heat-resistant cast steel with excellent thermal fatigue life | |
| EP3168318B1 (en) | Stainless steel alloys and turbocharger turbine housings formed from the stainless steel alloys | |
| EP1808504A1 (en) | Cast iron containing cobalt for use in steam turbines | |
| KR20160091041A (en) | Austenitic heat-resisting cast steel and turbine housing for turbocharger using the same | |
| CN117363955A (en) | Multi-type precipitated phase cooperative strengthening heat-resistant alloy and preparation method thereof | |
| US11434556B2 (en) | Austenitic alloys for turbochargers | |
| JP3752563B2 (en) | Heat resistant spheroidal graphite cast iron | |
| EP3575430B1 (en) | Stainless steel alloys, turbocharger components formed from the stainless steel alloys, and methods for manufacturing the same | |
| KR101918408B1 (en) | Austenitic steel excellent in high temperature strength | |
| CN114318104A (en) | Heat-resistant steel material for variable-section nozzle ring of gasoline engine | |
| US5259887A (en) | Heat-resistant, ferritic cast steel, exhaust equipment member made thereof | |
| EP3885464A1 (en) | Austenitic stainless steel alloys and turbocharger components formed from the stainless steel alloys | |
| EP3816317A1 (en) | Stainless steel alloys, turbocharger components formed from the stainless steel alloys, and methods for manufacturing the same | |
| JPH07197209A (en) | Ferritic heat resistant cast steel excellent in castability and exhaust system parts made thereof | |
| JP2981899B2 (en) | Piston ring material | |
| JPH06256908A (en) | Heat resistant cast steel and exhaust system parts using the same | |
| KR20160066574A (en) | Heat resistant cast steel having superior high temperature strength and oxidation resistant | |
| KR102135185B1 (en) | Austenitic steel excellent in room temperature strength and high temperature strength | |
| EP2910661B1 (en) | Stainless steel alloys, turbocharger turbine housings formed from the stainless steel alloys, and methods for manufacturing the same |
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 |