CN106396674A - Production method of high-toughness ceramic cutter - Google Patents
Production method of high-toughness ceramic cutter Download PDFInfo
- Publication number
- CN106396674A CN106396674A CN201610756712.5A CN201610756712A CN106396674A CN 106396674 A CN106396674 A CN 106396674A CN 201610756712 A CN201610756712 A CN 201610756712A CN 106396674 A CN106396674 A CN 106396674A
- Authority
- CN
- China
- Prior art keywords
- temperature
- pressure
- production method
- sintex
- heat treatment
- 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
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
- C04B35/48—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on zirconium or hafnium oxides, zirconates, zircon or hafnates
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/64—Burning or sintering processes
- C04B35/645—Pressure sintering
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3224—Rare earth oxide or oxide forming salts thereof, e.g. scandium oxide
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3224—Rare earth oxide or oxide forming salts thereof, e.g. scandium oxide
- C04B2235/3225—Yttrium oxide or oxide-forming salts thereof
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
- C04B2235/656—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes characterised by specific heating conditions during heat treatment
- C04B2235/6562—Heating rate
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
- C04B2235/66—Specific sintering techniques, e.g. centrifugal sintering
- C04B2235/661—Multi-step sintering
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Compositions Of Oxide Ceramics (AREA)
- Composite Materials (AREA)
Abstract
The invention discloses a production method of a high-toughness ceramic cutter. The method comprises the following steps: 1, carrying out precompression molding on a powdery raw material; 2, carrying out low-temperature heat treatment on a precompression molded product; and 3, carrying out hot press vibration sintering on a low-temperature heat treated product, rising the hot press vibration sintering temperature to 1700 DEG C from 1100 DEG C, rising the first pressure to 100 MPa from 80 MPa when the temperature rises to 1700 DEG C, continuously sintering for 20 min when the first pressure is 100 MPa, keeping the first pressure unchanged, reducing the temperature to 1100 DEG c, allowing the cooled product to stand for 3-5 min when the temperature is 1100 DEG C, heating the product to 1700 DEG C, and continuously applying a second pressure according to a frequency of 10-15/s in the hot press vibration sintering process. The ceramic cutter produced through the production method of the high-toughness ceramic cutter has the advantages of high strength and difficulty in fracture.
Description
Technical field
The present invention relates to a kind of production method of high tenacity sintex.
Background technology
Compared with other cutter material, the most significant shortcoming of sintex is exactly that fracture toughness is not enough, flexural strength and
Thermal shock resistance is poor, when cutting temperature changes, easily cracks.Important as its resisting breakage ability of evaluation
One of index, pottery needs to improve its hardness, bending strength and fracture toughness by suitable means, and is carrying out civilian pottery
During porcelain cutter articles for use, the other forms of sintex and tableware are easy to burst apart, unfilled corner, and the fracture toughness of ceramic cutting tool material is more
For important.
Content of the invention
The present invention has designed and developed a kind of production method of high tenacity sintex, and the intensity of prepared sintex is more
Height, not easy fracture.
The present invention provide technical scheme be：
A kind of production method of high tenacity sintex, including：
Powder material is carried out pre-molding by step (1), and powder material is made up of following components according to the mass fraction：Oxygen
Change 92～95 parts of zirconium, 5～6 parts of yittrium oxide, 4～6 parts of rare earth oxide；
The product that pre-molding obtains is carried out Low Temperature Heat Treatment by step (2), and temperature is warming up to from 600 DEG C～650 DEG C
The design temperature of Low Temperature Heat Treatment, heating rate is 15～25 DEG C/h, and the design temperature of Low Temperature Heat Treatment is 1000～1100 DEG C,
Apply constant pressure 50MPa under the design temperature of Low Temperature Heat Treatment, application time is 10min；
The product that Low Temperature Heat Treatment obtains is carried out hot pressing vibratory sintering by step (3), the temperature of hot pressing vibratory sintering from
1100 DEG C rise to 1700 DEG C, and heating rate is 30～50 DEG C/h, and when temperature is increased to 1700 DEG C, first pressure is from 80MPa
Rise to 100MPa, and rate of pressure rise is 2MPa/min, and first pressure persistently sinters 20min again in 100MPa；Afterwards
Keep first pressure constant, temperature is reduced to 1100 DEG C, rate of temperature fall be 50 DEG C/min, when being reduced to 1100 DEG C, standing 3～
5min, then it is warming up to 1700 DEG C；During hot pressing vibratory sintering, then it is continuously applied second pressure, the change of this second pressure
Amplitude is 20MPa, and frequency is 10～15 times/s.
Preferably, in the described production method of high tenacity sintex, in described step (1), powder material is by pressing
The following components composition of mass fraction meter：95 parts of zirconium oxide, 6 parts of yittrium oxide, 6 parts of rare earth oxide.
Preferably, in the described production method of high tenacity sintex, the temperature of described Low Temperature Heat Treatment is 1100
℃.
Preferably, in the described production method of high tenacity sintex, in described step (3), heating rate is 35
℃/h.
Preferably, the production method of described high tenacity sintex, also includes：Step (4) is by hot pressing vibratory sintering
The product obtaining is polished.
The intensity of the sintex obtained by production method of high tenacity sintex of the present invention is higher, not easily broken
Split.
Specific embodiment
The present invention is described in further detail below, with make those skilled in the art with reference to specification word being capable of evidence
To implement.
The present invention provides a kind of production method of high tenacity sintex, including：
Powder material is carried out pre-molding by step (1), and powder material is made up of following components according to the mass fraction：Oxygen
Change 92～95 parts of zirconium, 5～6 parts of yittrium oxide, 4～6 parts of rare earth oxide.
The product that pre-molding obtains is carried out Low Temperature Heat Treatment by step (2), and temperature is warming up to from 600 DEG C～650 DEG C
The design temperature of Low Temperature Heat Treatment, heating rate is 15～25 DEG C/h, and the design temperature of Low Temperature Heat Treatment is 1000～1100 DEG C,
Apply constant pressure 50MPa under the design temperature of Low Temperature Heat Treatment, application time is 10min.
The product that Low Temperature Heat Treatment obtains is carried out hot pressing vibratory sintering by step (3), the temperature of hot pressing vibratory sintering from
1100 DEG C rise to 1700 DEG C, and heating rate is 30～50 DEG C/h, and when temperature is increased to 1700 DEG C, first pressure is from 80MPa
Rise to 100MPa, and rate of pressure rise is 2MPa/min, and first pressure persistently sinters 20min again in 100MPa；Afterwards
Keep first pressure constant, temperature is reduced to 1100 DEG C, rate of temperature fall be 50 DEG C/min, when being reduced to 1100 DEG C, standing 3～
5min, then it is warming up to 1700 DEG C；During hot pressing vibratory sintering, then it is continuously applied second pressure, the change of this second pressure
Amplitude is 20MPa, and frequency is 10～15 times/s.
The present invention, in the Low Temperature Heat Treatment stage, employs the mode gradually heating up, and reaches setting value in temperature, also short
Time applies first pressure, and this both contributes to the disappearance of the open pore within material, so that the final Stupalox obtaining
The internal structure of tool is finer and close.
In the present invention, during hot pressing vibratory sintering, adopt staged heating mode, and the starting point of temperature and low temperature
The temperature of heat treatment is close, or even unanimously.This contributes to promoting material to progressively reach balance in microcosmic point, so that final make
It is more evenly distributed between the interface of each component in the internal structure of sintex obtaining；In addition, in the rear half stage of hot pressing, gradually
The process heating up is more beneficial for the contraction of the pore in material.
In addition, the present invention is during hot pressed sintering, when temperature is increased to highest, by first pressure gradually from 80MPa
It is increased to 100MPa, and control rate of pressure rise in certain value.At the maximum temperature, first pressure is gradually increased, can promote
Interface cohesion between different component is tightr.When reaching 100MPa, more persistently sinter 20min, contribute to knot between component
Close closely.Afterwards, temperature is rapidly reduced to 1100 DEG C, contributes to destroying the balance of material internal porosity, so that closing gas
Hole is easier to be excluded.
In addition the second pressure applying during hot pressing vibratory sintering, its amplitude of variation and change frequency pass through design,
The sealed porosity that hot pressing rear half stage is present within material can be made to be excluded.
The intensity of the sintex obtained by the present invention is high, and toughness is strong, and its hardness can reach 14.8GPa, fracture toughness
More than 15 can be reached, bending strength can reach 2094MPa.
Preferably, in the described production method of high tenacity sintex, in described step (1), powder material is by pressing
The following components composition of mass fraction meter：95 parts of zirconium oxide, 6 parts of yittrium oxide, 6 parts of rare earth oxide.
Preferably, in the described production method of high tenacity sintex, the temperature of described Low Temperature Heat Treatment is 1100
℃.
Preferably, in the described production method of high tenacity sintex, in described step (3), heating rate is 35
℃/h.
Preferably, the production method of described high tenacity sintex, also includes：Step (4) is by hot pressing vibratory sintering
The product obtaining is polished.
Although embodiment of the present invention is disclosed as above, it is not restricted to listed in description and embodiment
With, it can be applied to various suitable the field of the invention completely, for those skilled in the art, can be easily
Realize other modification, therefore under the general concept being limited without departing substantially from claim and equivalency range, the present invention does not limit
In specific details.
Claims (5)
1. a kind of production method of high tenacity sintex is it is characterised in that include：
Powder material is carried out pre-molding by step (1), and powder material is made up of following components according to the mass fraction：Zirconium oxide
92～95 parts, 5～6 parts of yittrium oxide, 4～6 parts of rare earth oxide；
The product that pre-molding obtains is carried out Low Temperature Heat Treatment by step (2), and temperature is warming up to low temperature from 600 DEG C～650 DEG C
The design temperature of heat treatment, heating rate is 15～25 DEG C/h, and the design temperature of Low Temperature Heat Treatment is 1000～1100 DEG C, low
Apply constant pressure 50MPa, application time is 10min under the design temperature that warm is processed；
The product that Low Temperature Heat Treatment obtains is carried out hot pressing vibratory sintering by step (3), and the temperature of hot pressing vibratory sintering is from 1100 DEG C
Rise to 1700 DEG C, heating rate is 30～50 DEG C/h, and when temperature is increased to 1700 DEG C, the first first pressure is from 80MPa
Rise to 100MPa, and rate of pressure rise is 2MPa/min, and the first first pressure persistently sinters 20min again in 100MPa；It
Keep first pressure constant afterwards, temperature is reduced to 1100 DEG C, rate of temperature fall is 50 DEG C/min, when being reduced to 1100 DEG C, stand 3
～5min, then it is warming up to 1700 DEG C；During hot pressing vibratory sintering, then it is continuously applied second pressure, the change of this second pressure
Change amplitude is 20MPa, and frequency is 10～15 times/s.
2. the production method of high tenacity sintex as claimed in claim 1 is it is characterised in that in described step (1), powder body
Raw material is made up of following components according to the mass fraction：95 parts of zirconium oxide, 6 parts of yittrium oxide, 6 parts of rare earth oxide.
3. the production method of high tenacity sintex as claimed in claim 1 is it is characterised in that the temperature of described Low Temperature Heat Treatment
Spend for 1100 DEG C.
4. the production method of high tenacity sintex as claimed in claim 1 is it is characterised in that in described step (3), heat up
Speed is 35 DEG C/h.
5. the production method of high tenacity sintex as claimed in claim 1 is it is characterised in that also include：Step (4) is by heat
The product that pressure vibratory sintering obtains is polished.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610756712.5A CN106396674A (en) | 2016-08-29 | 2016-08-29 | Production method of high-toughness ceramic cutter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610756712.5A CN106396674A (en) | 2016-08-29 | 2016-08-29 | Production method of high-toughness ceramic cutter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN106396674A true CN106396674A (en) | 2017-02-15 |
Family
ID=58002516
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610756712.5A Pending CN106396674A (en) | 2016-08-29 | 2016-08-29 | Production method of high-toughness ceramic cutter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106396674A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107188561A (en) * | 2017-06-30 | 2017-09-22 | 苏州吉云新材料技术有限公司 | A kind of high tenacity composite ceramics containing sub- nanometer spherical silicon powder |
| CN116477941A (en) * | 2023-04-19 | 2023-07-25 | 中物院成都科学技术发展中心 | Artificial jade pottery and preparation method thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101798217A (en) * | 2010-02-04 | 2010-08-11 | 山东轻工业学院 | Composite rare earth-stabilized zirconia-based multielement nano/micro composite ceramic tool and die material and preparation method thereof |
| CN102153346A (en) * | 2010-12-08 | 2011-08-17 | 赣州科盈结构陶瓷有限公司 | Rare-earth composite zirconium oxide ceramic fitness ball and preparation method of fitness ball |
| CN103204678A (en) * | 2012-01-16 | 2013-07-17 | 佛山市陶瓷研究所有限公司 | Ceramic cutting tool with ultrahigh strength and ultrahigh toughness, and preparation method thereof |
| CN103708832A (en) * | 2013-09-29 | 2014-04-09 | 雅安远创陶瓷有限责任公司 | Nano ceramic cutter and preparation method thereof |
| CN105777123A (en) * | 2016-02-04 | 2016-07-20 | 广东工业大学 | Method for preparing transparent yttrium oxide ceramic component through two-step pressure sintering |
-
2016
- 2016-08-29 CN CN201610756712.5A patent/CN106396674A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101798217A (en) * | 2010-02-04 | 2010-08-11 | 山东轻工业学院 | Composite rare earth-stabilized zirconia-based multielement nano/micro composite ceramic tool and die material and preparation method thereof |
| CN102153346A (en) * | 2010-12-08 | 2011-08-17 | 赣州科盈结构陶瓷有限公司 | Rare-earth composite zirconium oxide ceramic fitness ball and preparation method of fitness ball |
| CN103204678A (en) * | 2012-01-16 | 2013-07-17 | 佛山市陶瓷研究所有限公司 | Ceramic cutting tool with ultrahigh strength and ultrahigh toughness, and preparation method thereof |
| CN103708832A (en) * | 2013-09-29 | 2014-04-09 | 雅安远创陶瓷有限责任公司 | Nano ceramic cutter and preparation method thereof |
| CN105777123A (en) * | 2016-02-04 | 2016-07-20 | 广东工业大学 | Method for preparing transparent yttrium oxide ceramic component through two-step pressure sintering |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107188561A (en) * | 2017-06-30 | 2017-09-22 | 苏州吉云新材料技术有限公司 | A kind of high tenacity composite ceramics containing sub- nanometer spherical silicon powder |
| CN116477941A (en) * | 2023-04-19 | 2023-07-25 | 中物院成都科学技术发展中心 | Artificial jade pottery and preparation method thereof |
| CN116477941B (en) * | 2023-04-19 | 2024-02-23 | 中物院成都科学技术发展中心 | Artificial jade pottery and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106079032B (en) | A kind of gel-casting method based on agarose, ceramic slurry mixed solution | |
| CN104291814B (en) | Ceramic earphone and manufacture method | |
| CN104446419B (en) | A kind of preparation method of high-orientation Conjugate ferrite magnetostriction materials | |
| CN101862226A (en) | Manufacture method of zirconium oxide ceramic false tooth blanks | |
| CN101948964A (en) | Method for preparing biomedical porous titanium and titanium alloy material | |
| CN109534817A (en) | A kind of orienting stephanoporate structure preparation method of polymer pyrolysis class ceramics | |
| CN106904977A (en) | A kind of method that two-step sintering method prepares the tough Si3N4 ceramic materials of table hard-core | |
| CN106396674A (en) | Production method of high-toughness ceramic cutter | |
| CN107573061A (en) | The manufacture method of honeycomb blind hole toughened zirconium oxide ceramic shell and its application | |
| CN108751996A (en) | A kind of the boron carbide ceramics material and its plasma agglomeration preparation process of graphene toughening | |
| CN105331843A (en) | Boron carbide nozzle and preparation method thereof | |
| WO2008153177A1 (en) | Dense boron carbide ceramic and process for producing the same | |
| CN106518060A (en) | Manufacturing method of ceramic mobile phone back cover | |
| CN104772464A (en) | Method for preparing orthopaedic implants | |
| Nakahira et al. | Fabrication of Porous Hydroxyapatite Using Hydrothermal Hot Pressing and Post‐Sintering | |
| CN106396673A (en) | Processing technology of ceramic cutter | |
| CN106396672A (en) | Production method of ceramic cutte | |
| CN104658917B (en) | A kind of preparation method of the metal-based compound electronics packaging part containing high-volume fractional SiC | |
| RU2015106834A (en) | MULTI-COMPONENT COMPOUNDS OF PLASTIC COMPOSITIONS FOR THE PRODUCTION OF MEDICAL PRODUCTS WITH FUNCTIONAL SURFACE | |
| CN104876584B (en) | A kind of zirconium silicide based composite ceramic material and preparation method thereof | |
| CN106380196A (en) | Molding technology of ceramic cutting tool | |
| CN107954714A (en) | A kind of method of ultrasonic wave auxiliary oscillating pressure sintering zirconia ceramics | |
| CN106348750A (en) | Method for improving toughness of ceramic cutting tool | |
| CN106830966A (en) | Carbon/carbon compound material base substrate and forming method and application based on carbon fiber powder | |
| CN102796908A (en) | Preparation method of medical porous titanium implant material |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20170215 |
|
| RJ01 | Rejection of invention patent application after publication |