CN110396652A - A kind of SiC Fiber Reinforced Al Matrix Composites and preparation method thereof - Google Patents
A kind of SiC Fiber Reinforced Al Matrix Composites and preparation method thereof Download PDFInfo
- Publication number
- CN110396652A CN110396652A CN201910799424.1A CN201910799424A CN110396652A CN 110396652 A CN110396652 A CN 110396652A CN 201910799424 A CN201910799424 A CN 201910799424A CN 110396652 A CN110396652 A CN 110396652A
- Authority
- CN
- China
- Prior art keywords
- silicon carbide
- carbide fibre
- aluminium alloy
- precast body
- furnace
- 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
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C47/00—Making alloys containing metallic or non-metallic fibres or filaments
- C22C47/02—Pretreatment of the fibres or filaments
- C22C47/04—Pretreatment of the fibres or filaments by coating, e.g. with a protective or activated covering
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C47/00—Making alloys containing metallic or non-metallic fibres or filaments
- C22C47/02—Pretreatment of the fibres or filaments
- C22C47/06—Pretreatment of the fibres or filaments by forming the fibres or filaments into a preformed structure, e.g. using a temporary binder to form a mat-like element
- C22C47/062—Pretreatment of the fibres or filaments by forming the fibres or filaments into a preformed structure, e.g. using a temporary binder to form a mat-like element from wires or filaments only
- C22C47/066—Weaving wires
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C47/00—Making alloys containing metallic or non-metallic fibres or filaments
- C22C47/08—Making alloys containing metallic or non-metallic fibres or filaments by contacting the fibres or filaments with molten metal, e.g. by infiltrating the fibres or filaments placed in a mould
- C22C47/12—Infiltration or casting under mechanical pressure
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C49/00—Alloys containing metallic or non-metallic fibres or filaments
- C22C49/02—Alloys containing metallic or non-metallic fibres or filaments characterised by the matrix material
- C22C49/04—Light metals
- C22C49/06—Aluminium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C49/00—Alloys containing metallic or non-metallic fibres or filaments
- C22C49/14—Alloys containing metallic or non-metallic fibres or filaments characterised by the fibres or filaments
Abstract
The invention discloses a kind of SiC Fiber Reinforced Al Matrix Composites, are made of silicon carbide fibre, metallic interfacial layer, enhancing particle and aluminium alloy.Preparation method: (1) silicon carbide fibre precast body is put into high temperature heat treatment furnace except glue handled；(2) the silicon carbide fibre precast body distilled water handled well except glue is cleaned by ultrasonic and is dried；(3) one layer of metallic interfacial layer is prepared in the silicon carbide fibre precast body dried using electroless plating method；(5) enhancing particle is uniformly added in molten aluminium alloy, and molten aluminium alloy is infiltrated up in the precast body for preparing boundary layer, obtain SiC Fiber Reinforced Al Matrix Composites.The present invention solves the problems, such as the interface compatibility of silicon carbide fibre and aluminium alloy, hence it is evident that improves aluminium alloy to the wetability of silicon carbide fibre, has given full play to the toughened and reinforced effect of silicon carbide fibre.Composite property prepared by the present invention is excellent, is the important candidate advanced composite material of aerospace field.
Description
Technical field
The present invention relates to a kind of aluminum matrix composite and preparation method thereof, in particular to a kind of silicon carbide fibre enhancing is compound
Material and preparation method thereof.
Background technique
Aluminum matrix composite is because having the excellent spies such as low density, Gao Biqiang, Gao Bimo, high-wearing feature and low thermal coefficient of expansion
Property, it has been widely applied to the fields such as aerospace, automobile, Electronic Packaging.But with the development of science and technology, especially aviation is navigated
Requirement of its field to material property increasingly improves, and there is an urgent need to carry out performance boost to aluminum matrix composite.Currently, aluminium base is multiple
Condensation material is broadly divided into particle enhanced aluminum-based composite material and fiber reinforced aluminum matrix composites.Particle enhanced aluminum-based composite material
Although intensity with higher, its fracture toughness is poor, and use reliability is insufficient；Fiber reinforced aluminum matrix composites, especially
It is the intensity that continuous fiber reinforcement aluminum matrix composite not only can guarantee composite material, but also can improve the fracture toughness of material and resist
Impact property etc..And carbon fiber is currently mainly used in fiber reinforced aluminum matrix composites, carbon fiber is caused due to meeting and reactive aluminum
Fibre strength decline keeps the preparation process of material more complicated so multiple interface processing must be carried out to carbon fiber.
Silicon carbide fibre is as a kind of typical high-performance ceramic fiber, and preferable with the interface compatibility of aluminium, the two is not
It can chemically react, and silicon carbide fibre has good high temperature resistance and oxidation resistent susceptibility, it is multiple to be used for aluminium base
Condensation material can effectively improve intensity, heat resistance, corrosion resistance and fracture toughness of material etc..
Authorization Notice No. is that the Chinese invention patent of CN107513675B discloses a kind of silicon carbide fibre Shu Zengqiang aluminium base
The preparation method of composite material is woven into fiber cloth using quartz fibre beam, suppresses with graphite powder stratiform and constitutes silicon carbide fibre
Aluminum or aluminum alloy foil is carried out stratiform with silicon carbide fibre cloth and replaces superposition by cloth, and the precast body before obtaining compound suppressing sintering will
Precast body carries out compacting sintering, cooling, obtains the netted reinforced aluminum matrix composites of long filament silicon carbide fibre beam.
Authorization Notice No. is that the Chinese invention patent of CN108385040B discloses a kind of chopped carbon fiber enhancing magnesium-aluminum-based
The preparation method of composite material includes the following steps: to provide zirconium carbide powder and silicon carbide powder；To zirconium carbide powder and
Silicon carbide powder carries out ball milling, obtains the first mixed-powder；Isostatic cool pressing is carried out to the first mixed-powder, obtains the first enhancing
Grain block；Vacuum heat treatment is carried out to the first enhancing particle population, obtains the second enhancing particle population；By magnesium-aluminum metal ingot and
Second enhancing particle population, which is put into vacuum furnace, carries out Compound Heat Treatment, obtains granule reinforced magnesium aluminum metal liquid；It provides short
Carbon fiber is cut, and chopped carbon fiber is preheated；Semi-solid Stirring is carried out to granule reinforced magnesium aluminum metal liquid, is stirred in semisolid
During mixing, the chopped carbon fiber by preheating is added into granule reinforced magnesium aluminum metal liquid, obtains chopped carbon fiber enhancing
Magnesium-aluminum metal liquid；It is poured using chopped carbon fiber enhancing magnesium-aluminum metal liquid, it is compound to obtain chopped carbon fiber enhancing magnesium-aluminum-based
Material.
Summary of the invention
It is an object of the invention to propose a kind of SiC Fiber Reinforced Al Matrix Composites and preparation method thereof, thus gram
The shortcomings that taking current material and technology.
To achieve the above object, the present invention provides a kind of SiC Fiber Reinforced Al Matrix Composites, bulk density is
2.3~2.7g/cm3, it is made of silicon carbide fibre, metallic interfacial layer, enhancing particle and aluminium alloy, it is characterised in that silicon carbide is fine
Dimension is woven into precast body in advance, and metallic interfacial layer is wrapped in silicon carbide fibre surface, enhances particle and aluminium alloy filler is being carbonized
In silica fibre precast body；The silicon carbide fibre precursor structure is unidirectional fibre felt, fiber cloth lamination, 2.5D, three-dimensional volume
One of knit with needled carbon felt, fiber volume fraction is 20 ~ 40%；The metallic interfacial layer is one of copper and mickel；Institute
The enhancing particle stated is SiC, Al2O3, one of TiC and ZrC, enhancing grain volume fraction is 0.5 ~ 5%, enhances grain diameter
It is 0.5 ~ 5 μm.
A kind of preparation method of SiC Fiber Reinforced Al Matrix Composites, it is characterised in that the step including following sequences
It is rapid:
(1) silicon carbide fibre precast body is put into high temperature heat treatment furnace except glue is handled, treatment temperature is 300 ~ 500 DEG C, processing
Time is 0.5 ~ 2h；
(2) the silicon carbide fibre precast body that glue is handled well will be removed in step (1) to be cleaned by ultrasonic with distilled water, then dry；
(3) one layer of metallic interfacial layer is prepared in the silicon carbide fibre precast body dried in step (2) using electroless plating method；
(4) aluminium alloy block being put into melt process in high-temperature vacuum furnace, treatment temperature is 700 ~ 900 DEG C, 1 ~ 3h of soaking time,
Then enhancing particle is added in molten aluminium alloy and is stirred evenly；
(5) the silicon carbide fibre precast body for preparing metallic interfacial layer in step (3) is fitted into mold and is fixed, be put into infiltration
In furnace, the molten aluminium alloy prepared in step (4) is put into infiltration furnace, infiltration furnace is warming up to 500 ~ 700 DEG C, then by aluminium
In alloy molten solution vacuum pouring to mold, pours and be poured in air pressure in rear furnace and increase to 1.0 ~ 3.0MPa, furnace cooling after heat-insulation pressure keeping
Demoulding obtains SiC Fiber Reinforced Al Matrix Composites.
Compared with current material and technology, the invention has the following beneficial effects: (1) to be woven using continuous carbofrax fibre
At precast body, the toughened and reinforced effect of silicon carbide fibre is not only effectively played, but also effectively increase the structural stability of composite material
And performance reliability；(2) processing of plating metal boundary layer is carried out to silicon carbide fibre, improves silicon carbide fibre and molten aluminium alloy
Wetability, improve the infiltration efficiency of aluminium alloy, reduce the defect of composite inner, significantly increase composite material
Mechanical property；(3) particle reinforced aluminum alloy matrix is used, wear-resisting property, hardness, rigidity and the temperature tolerance of composite material are improved
Energy is equal, extends the application field of composite material.
Specific embodiment
Combined with specific embodiments below, the present invention is furture elucidated, it should be understood that these embodiments are merely to illustrate the present invention
Rather than limit the scope of the invention, after the present invention has been read, those skilled in the art are to various equivalences of the invention
It is as defined in the appended claims that the modification of form falls within the application.
Embodiment
A kind of SiC Fiber Reinforced Al Matrix Composites, density 2.5g/cm3, by silicon carbide fibre, metal interface
Layer, enhancing particle and aluminium alloy composition, it is characterised in that silicon carbide fibre is woven into precast body in advance, and metallic interfacial layer is wrapped in
Silicon carbide fibre surface enhances particle and aluminium alloy filler in silicon carbide fibre precast body；The silicon carbide fibre is prefabricated
Body structure is 2.5D, fiber volume fraction 35%；The metallic interfacial layer is nickel；The enhancing particle is SiC, enhancing
Grain volume fraction is 3%, and enhancing grain diameter is 1 μm.
A kind of preparation method of SiC Fiber Reinforced Al Matrix Composites, it is characterised in that the step including following sequences
It is rapid:
(1) silicon carbide fibre precast body is put into vacuum high-temperature heat-treatment furnace except glue is handled, treatment temperature is 450 DEG C, processing
Time is 1h；
(2) the silicon carbide fibre precast body that glue is handled well will be removed in step (1) to be cleaned by ultrasonic with distilled water, then dry；
(3) one layer of metallic interfacial layer is prepared in the silicon carbide fibre precast body dried in step (2) using electroless plating method；
(4) aluminium alloy block is put into melt process in high-temperature vacuum furnace, treatment temperature is 750 DEG C, soaking time 2h, then will
Enhancing particle is added in molten aluminium alloy and stirs evenly；
(5) the silicon carbide fibre precast body for preparing metallic interfacial layer in step (3) is fitted into mold and is fixed, be put into infiltration
In furnace, the molten aluminium alloy prepared in step (4) is put into infiltration furnace, infiltration furnace is warming up to 550 DEG C, then by aluminium alloy
In melt vacuum pouring to mold, pours and be poured in air pressure in rear furnace and increase to 2.0MPa, furnace cooling demoulds to obtain after heat-insulation pressure keeping
SiC Fiber Reinforced Al Matrix Composites.
The above is only a specific embodiment of the present invention, but the design concept of the present invention is not limited to this, all to utilize this
Design makes a non-material change to the present invention, and should belong to the behavior for invading the scope of protection of the invention.But it is all not take off
Content from technical solution of the present invention, it is to the above embodiments according to the technical essence of the invention any type of simply to repair
Change, equivalent variations and remodeling, still falls within the protection scope of technical solution of the present invention.
Claims (2)
1. a kind of SiC Fiber Reinforced Al Matrix Composites, bulk density is 2.3 ~ 2.7g/cm3, by silicon carbide fibre, metal
Boundary layer, enhancing particle and aluminium alloy composition, it is characterised in that silicon carbide fibre is woven into precast body, metallic interfacial layer packet in advance
It is rolled in silicon carbide fibre surface, enhances particle and aluminium alloy filler in silicon carbide fibre precast body；The silicon carbide fibre
Precursor structure is one of unidirectional fibre felt, fiber cloth lamination, 2.5D, 3 D weaving and needled carbon felt, fiber volume fraction
Number is 20 ~ 40%；The metallic interfacial layer is one of copper and mickel；The enhancing particle is SiC, Al2O3, TiC and ZrC
One of, enhancing grain volume fraction is 0.5 ~ 5%, and enhancing grain diameter is 0.5 ~ 5 μm.
2. a kind of preparation method of SiC Fiber Reinforced Al Matrix Composites, it is characterised in that include the steps that following sequences:
(1) silicon carbide fibre precast body is put into high temperature heat treatment furnace except glue is handled, treatment temperature is 300 ~ 500 DEG C, processing
Time is 0.5 ~ 2h；
(2) the silicon carbide fibre precast body that glue is handled well will be removed in step (1) to be cleaned by ultrasonic with distilled water, then dry；
(3) one layer of metallic interfacial layer is prepared in the silicon carbide fibre precast body dried in step (2) using electroless plating method；
(4) aluminium alloy block being put into melt process in high-temperature vacuum furnace, treatment temperature is 700 ~ 900 DEG C, 1 ~ 3h of soaking time,
Then enhancing particle is added in molten aluminium alloy and is stirred evenly；
(5) the silicon carbide fibre precast body for preparing metallic interfacial layer in step (3) is fitted into mold and is fixed, be put into infiltration
In furnace, the molten aluminium alloy prepared in step (4) is put into infiltration furnace, infiltration furnace is warming up to 500 ~ 700 DEG C, then by aluminium
In alloy molten solution vacuum pouring to mold, pours and be poured in air pressure in rear furnace and increase to 1.0 ~ 3.0MPa, furnace cooling after heat-insulation pressure keeping
Demoulding obtains SiC Fiber Reinforced Al Matrix Composites.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910799424.1A CN110396652A (en) | 2019-08-28 | 2019-08-28 | A kind of SiC Fiber Reinforced Al Matrix Composites and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910799424.1A CN110396652A (en) | 2019-08-28 | 2019-08-28 | A kind of SiC Fiber Reinforced Al Matrix Composites and preparation method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110396652A true CN110396652A (en) | 2019-11-01 |
Family
ID=68329345
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910799424.1A Pending CN110396652A (en) | 2019-08-28 | 2019-08-28 | A kind of SiC Fiber Reinforced Al Matrix Composites and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110396652A (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111850339A (en) * | 2020-06-24 | 2020-10-30 | 南昌航空大学 | Composite material with high thermal conductivity and incomplete cladding of interface phase, and preparation method and test method thereof |
| CN112779480A (en) * | 2019-11-06 | 2021-05-11 | 南京航空航天大学 | Interface modified fiber reinforced metal matrix composite material and preparation method thereof |
| CN113355610A (en) * | 2020-12-30 | 2021-09-07 | 中北大学 | Metal wire reinforced aluminum matrix composite material and preparation method thereof |
| WO2022134214A1 (en) * | 2020-12-22 | 2022-06-30 | 苏州宏久航空防热材料科技有限公司 | Continuous electrophoretic deposition modified carbon fiber reinforced multi-matrix composite material and preparation method therefor |
| CN115679228A (en) * | 2022-11-21 | 2023-02-03 | 中南大学 | Silicon carbide fiber reinforced aluminum-based composite material and preparation method and application thereof |
| CN115852275A (en) * | 2022-03-31 | 2023-03-28 | 南京航空航天大学 | Ultra-light high-strength fiber reinforced aluminum-lithium alloy composite material and preparation method thereof |
| CN116141774A (en) * | 2023-02-16 | 2023-05-23 | 江苏礼德铝业有限公司 | Aluminum plate with ceramic fibers and manufacturing method thereof |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101418402A (en) * | 2008-12-12 | 2009-04-29 | 大亚科技股份有限公司 | Sub-micron granule strengthening aluminum base composite material for automobile hub and preparation method thereof |
| CN109055874A (en) * | 2018-08-17 | 2018-12-21 | 苏州宏久航空防热材料科技有限公司 | A kind of boundary layer enhancing biradical fibrous composite of aluminium alloy-silicon carbide and preparation method thereof |
-
2019
- 2019-08-28 CN CN201910799424.1A patent/CN110396652A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101418402A (en) * | 2008-12-12 | 2009-04-29 | 大亚科技股份有限公司 | Sub-micron granule strengthening aluminum base composite material for automobile hub and preparation method thereof |
| CN109055874A (en) * | 2018-08-17 | 2018-12-21 | 苏州宏久航空防热材料科技有限公司 | A kind of boundary layer enhancing biradical fibrous composite of aluminium alloy-silicon carbide and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 孟超: "《深入探讨新型金属材料 超级合金的性能与应用》", 31 May 2018, 电子科技大学出版社 * |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112779480A (en) * | 2019-11-06 | 2021-05-11 | 南京航空航天大学 | Interface modified fiber reinforced metal matrix composite material and preparation method thereof |
| CN112779480B (en) * | 2019-11-06 | 2022-03-22 | 南京航空航天大学 | Interface modified fiber reinforced metal matrix composite material and preparation method thereof |
| CN111850339A (en) * | 2020-06-24 | 2020-10-30 | 南昌航空大学 | Composite material with high thermal conductivity and incomplete cladding of interface phase, and preparation method and test method thereof |
| WO2022134214A1 (en) * | 2020-12-22 | 2022-06-30 | 苏州宏久航空防热材料科技有限公司 | Continuous electrophoretic deposition modified carbon fiber reinforced multi-matrix composite material and preparation method therefor |
| CN113355610A (en) * | 2020-12-30 | 2021-09-07 | 中北大学 | Metal wire reinforced aluminum matrix composite material and preparation method thereof |
| CN115852275A (en) * | 2022-03-31 | 2023-03-28 | 南京航空航天大学 | Ultra-light high-strength fiber reinforced aluminum-lithium alloy composite material and preparation method thereof |
| CN115852275B (en) * | 2022-03-31 | 2024-01-09 | 南京航空航天大学 | Ultra-light high-strength fiber reinforced aluminum-lithium alloy composite material and preparation method thereof |
| CN115679228A (en) * | 2022-11-21 | 2023-02-03 | 中南大学 | Silicon carbide fiber reinforced aluminum-based composite material and preparation method and application thereof |
| CN115679228B (en) * | 2022-11-21 | 2024-01-26 | 中南大学 | Silicon carbide fiber reinforced aluminum-based composite material and preparation method and application thereof |
| CN116141774A (en) * | 2023-02-16 | 2023-05-23 | 江苏礼德铝业有限公司 | Aluminum plate with ceramic fibers and manufacturing method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110396652A (en) | A kind of SiC Fiber Reinforced Al Matrix Composites and preparation method thereof | |
| CN103343274B (en) | High-thermal-conductivity graphite-aluminium strengthens aluminum graphite composite and preparation technology thereof | |
| CN106812837B (en) | Aluminum-based composite material brake disc and preparation method thereof | |
| CN103939509B (en) | A kind of Al/Sic and Cu/Sic composite materials friction pair for rail vehicle and preparation method thereof | |
| CN107326211B (en) | A kind of high body part ceramic-metal laminar composite and preparation method thereof | |
| CN103075445B (en) | A kind of ceramic/metal composite materials brake lining for bullet train and preparation method thereof | |
| CN109627028A (en) | A kind of 3D printing carbon fiber toughened silicon carbide pottery aluminium composite material and preparation method thereof | |
| WO2015169024A1 (en) | Friction disk of metal/continuous-structure phase ceramic composite material and method for manufacturing same | |
| CN112267039B (en) | Preparation process of high volume fraction silicon carbide particle reinforced aluminum matrix composite | |
| CN105385875B (en) | Preparation method for shell-nacreous-layer-imitating magnesium-based composite material | |
| CN108441791A (en) | A kind of metal ceramic-based composite material of fibre reinforced | |
| CN110205536B (en) | Titanium/titanium carbide core-shell structure reinforced aluminum-based composite material and preparation method thereof | |
| CN101381242A (en) | Method for preparing crucible for smelting titanium and titanium alloys | |
| CN110724847B (en) | Method for preparing bicontinuous phase composite material by pressureless infiltration | |
| CN108975936A (en) | A kind of graphite ceramic is compound and preparation method thereof | |
| CN107760894A (en) | A kind of preparation method of aluminum matrix composite automobile brake disc | |
| CN109913686A (en) | Modified SiC reinforced aluminum matrix composites in a kind of surface and preparation method thereof | |
| CN110157940A (en) | A kind of laser synthesizing coat of silicon carbide reinforced aluminum matrix composites | |
| CN111690840B (en) | Amorphous phase silicate particle and SiC particle reinforced aluminum matrix composite material and preparation | |
| CN1789447A (en) | Method and apparatus for preparing VC-FeNiCr composite material by employing aluminothermy-quick solidification process | |
| CN104561845A (en) | Aluminum matrix composite for preparing automobile brake disc | |
| CN102416462B (en) | A kind of preparation method of metal-base composites of local enhancement | |
| CN108975924A (en) | The preparation method of one type Z-pins metal bar enhancing carbon ceramic composite material | |
| CN111515360A (en) | Preparation method of cylindrical multilayer composite casting | |
| Akgün et al. | Effect of aging heat treatment on mechanical properties of expanded glass reinforced syntactic metal foam |
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 | ||
| WD01 | Invention patent application deemed withdrawn after publication | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20191101 |