CN116607056A - High-strength stretch-proof tantalum-tungsten alloy wire and preparation method thereof - Google Patents

High-strength stretch-proof tantalum-tungsten alloy wire and preparation method thereof Download PDF

Info

Publication number
CN116607056A
CN116607056A CN202310619689.5A CN202310619689A CN116607056A CN 116607056 A CN116607056 A CN 116607056A CN 202310619689 A CN202310619689 A CN 202310619689A CN 116607056 A CN116607056 A CN 116607056A
Authority
CN
China
Prior art keywords
tantalum
tungsten
powder
alloy wire
tungsten alloy
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
Application number
CN202310619689.5A
Other languages
Chinese (zh)
Inventor
王建生
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Baoji Hengye Nonferrous Metal Technology Co ltd
Original Assignee
Baoji Hengye Nonferrous Metal Technology Co ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Baoji Hengye Nonferrous Metal Technology Co ltd filed Critical Baoji Hengye Nonferrous Metal Technology Co ltd
Priority to CN202310619689.5A priority Critical patent/CN116607056A/en
Publication of CN116607056A publication Critical patent/CN116607056A/en
Pending legal-status Critical Current

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C27/00Alloys based on rhenium or a refractory metal not mentioned in groups C22C14/00 or C22C16/00
    • C22C27/02Alloys based on vanadium, niobium, or tantalum
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/02Compacting only
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/10Sintering only
    • B22F3/1003Use of special medium during sintering, e.g. sintering aid
    • B22F3/1007Atmosphere
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F5/00Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product
    • B22F5/12Manufacture of workpieces or articles from metallic powder characterised by the special shape of the product of wires
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C1/00Making non-ferrous alloys
    • C22C1/04Making non-ferrous alloys by powder metallurgy
    • C22C1/045Alloys based on refractory metals

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Powder Metallurgy (AREA)

Abstract

The invention relates to the technical field of tantalum-tungsten alloy wires, in particular to a high-strength stretch-proof tantalum-tungsten alloy wire and a preparation method thereof. The high-strength tantalum powder comprises tantalum powder and tungsten powder, wherein the content of the tantalum powder is 75-90%, and the content of the tungsten powder is 10-25%; the method comprises the following steps: s1, selecting high-purity tantalum and tungsten powder; s2, adding refined tantalum and tungsten powder into a ball milling bottle for high-energy mixing; s3, placing the mixed powder into a mandrel die, and performing top-injection compression molding; s4, sintering treatment is carried out in vacuum or hydrogen flow, and drawing treatment is carried out to obtain tantalum-tungsten alloy wires; the unique properties of tantalum and tungsten are utilized in the invention, the alloy has higher strength and stability and higher corrosion resistance; the tantalum-tungsten alloy wire with smaller diameter and longer size can be prepared by the special process in the preparation method, and the tantalum-tungsten alloy wire has higher strength and stability.

Description

High-strength stretch-proof tantalum-tungsten alloy wire and preparation method thereof
Technical Field
The invention relates to the technical field of tantalum-tungsten alloy wires, in particular to a high-strength stretch-proof tantalum-tungsten alloy wire and a preparation method thereof.
Background
In the fields of iron and steel, metallurgy, machining and the like, tantalum-tungsten alloy has become an important high-temperature corrosion-resistant metal material. The application field of the material is continuously expanded, and the requirements on the mechanical property and the processing property of the material are also higher and higher.
However, the problems of batch difference, high preparation difficulty and the like still exist in the traditional production process and alloy formula, so that the tantalum-tungsten alloy has different strength and poor stability, and the requirement of high-end application is difficult to meet; meanwhile, tantalum-tungsten alloy is resistant to poor sintering, and the process for preparing the wire rod is difficult.
The main problems in the prior art are poor strength and stability of the tantalum-tungsten alloy; the content and microstructure change of each element in the tantalum-tungsten alloy can influence the mechanical property of the material, meanwhile, the tantalum-tungsten alloy is also easily influenced by a preparation process, and the problems of internal defects, deformation and the like of the material can occur in the preparation process, so that the performance of the material is poor and the stability is insufficient; therefore, in order to solve the problems in the prior art, a new preparation process and alloy formulation need to be searched for to solve the problem of poor tensile resistance, thereby improving the usability and application field of the tantalum-tungsten alloy.
Disclosure of Invention
The invention aims to provide a high-strength stretch-proof tantalum-tungsten alloy wire and a preparation method thereof, so as to solve the problems in the background art.
In order to achieve the above object, in one aspect, the present invention provides a high-strength stretch-proof tantalum-tungsten alloy wire, which comprises tantalum powder and tungsten powder, wherein the content of the tantalum powder is 75-90%, and the content of the tungsten powder is 10-25%, and the proportion design is carefully designed and verified, so that the tantalum-tungsten alloy wire has excellent mechanical properties and good corrosion resistance.
As a further improvement of the technical scheme, the diameter of the tantalum-tungsten alloy wire is between 0.1 and 1.0 mm.
In another aspect, the present invention provides a method for preparing a high strength stretch-proof tantalum-tungsten alloy wire as described in any one of the above, comprising the steps of:
s1, preparing raw materials: selecting high-purity tantalum and tungsten powder, and controlling the proportion of the two raw materials at the same time;
s2, stirring and mixing: adding refined tantalum and tungsten powder into a ball milling bottle, and performing high-energy mixing in a ball milling mode to uniformly mix the tantalum powder and the tungsten powder;
s3, press forming: placing the mixed powder into a mandrel die, and adopting top injection compression molding to prepare a molded blank;
s4, sintering treatment: and sintering the formed blank in vacuum or hydrogen flow, and drawing to obtain the tantalum-tungsten alloy wire after the formed blank is sintered.
Preferably, in the step S2, the ball milling rotating speed is 200-400r/min.
Preferably, in the step S3, the top injection pressure is 50-200MPa.
Preferably, in the step S4, the sintering temperature is 2200-2300 ℃.
Preferably, in the step S4, the heat treatment time is 12-24 hours.
Compared with the traditional method, the preparation method provided by the invention is simpler, the preparation process is more convenient, the preparation cost can be reduced, and the prepared tantalum-tungsten alloy wire has higher strength and stability, thereby being beneficial to quick popularization and application; has high efficiency and repeatability, and can be produced in batch.
Compared with the prior art, the invention has the beneficial effects that:
in the high-strength stretch-proof tantalum-tungsten alloy wire and the preparation method thereof, the unique properties of tantalum and tungsten are utilized, so that the wire has higher strength and stability and higher corrosion resistance; the tantalum-tungsten alloy wire with smaller diameter and longer size can be prepared by a special process in the preparation method, so that the tantalum-tungsten alloy wire has higher strength and stability; the preparation method is simple, low in cost, high in operability and easy for mass production.
Drawings
Fig. 1 is an overall flow diagram of the present invention.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The embodiment of the invention provides a high-strength stretch-proof tantalum-tungsten alloy wire, which comprises tantalum powder and tungsten powder, wherein the content of the tantalum powder is 75-90%, and the content of the tungsten powder is 10-25%;
the diameter of the tantalum-tungsten alloy wire is between 0.1 and 1.0 mm; the length of the steel plate reaches tens of meters, and the steel plate has higher strength and tensile resistance.
According to the embodiment of the invention, as shown in fig. 1, the preparation method for preparing the high-strength stretch-proof tantalum-tungsten alloy wire is provided, and comprises the following specific steps:
(1) The preparation method comprises the following steps: high purity tantalum and tungsten powder is selected, and the proportion of the two raw materials is controlled.
(2) Stirring and mixing: adding refined tantalum and tungsten powder into a ball milling bottle, and performing high-energy mixing in a ball milling mode to uniformly mix the tantalum and tungsten powder, wherein the ball milling rotating speed is 200-400r/min.
(3) And (5) press forming: and (3) placing the mixed powder into a mandrel die, adopting top injection, and performing compression molding under the condition that the top injection pressure is 50-200MPa to obtain a molded blank.
(4) Sintering: sintering the formed blank in vacuum or hydrogen flow at 2200-2300 deg.c for 12-24 hr, and drawing to obtain tantalum-tungsten alloy wire with diameter of 0.6 mm.
Compared with the traditional method, the preparation method provided by the invention is simpler, the preparation process is more convenient, the preparation cost can be reduced, the tantalum-tungsten alloy wire is formed efficiently by a special process in the preparation method, and meanwhile, the tantalum-tungsten alloy wire with smaller diameter and longer size can be prepared, so that the tantalum-tungsten alloy wire is suitable for commercial production; the preparation method has the advantages of short preparation period, low production cost, mass production and the like, provides a brand new technical solution for the metal material preparation industry, and has wide practical application prospect and economic value.
The high-strength stretch-proof tantalum-tungsten alloy wire provided by the invention is further described by the following specific examples according to different raw material amounts.
Example 1
(1) The preparation method comprises the following steps: high purity tantalum and tungsten powders were selected, wherein the tantalum powder content was 75% and the tungsten powder content was 25%.
(2) Stirring and mixing: adding refined tantalum and tungsten powder into a ball milling bottle, and performing high-energy mixing in a ball milling mode to uniformly mix the tantalum and tungsten powder, wherein the ball milling rotating speed is 200r/min.
(3) And (5) press forming: and (3) placing the mixed powder into a mandrel die, performing top injection, and performing compression molding under the condition that the top injection pressure is 50MPa to obtain a molded blank.
(4) Sintering: sintering the formed blank in vacuum or hydrogen flow at 2200 deg.c for 12 hr, and drawing to obtain tantalum-tungsten alloy wire with diameter of 0.1 mm.
Example 2
(1) The preparation method comprises the following steps: high purity tantalum and tungsten powders were selected, wherein the tantalum powder content was 78% and the tungsten powder content was 22%.
(2) Stirring and mixing: adding refined tantalum and tungsten powder into a ball milling bottle, and performing high-energy mixing in a ball milling mode to uniformly mix the tantalum and tungsten powder, wherein the ball milling rotating speed is 250r/min.
(3) And (5) press forming: and (3) placing the mixed powder into a mandrel die, performing top injection, and performing compression molding under the condition that the top injection pressure is 80MPa to obtain a molded blank.
(4) Sintering: sintering the formed blank in vacuum or hydrogen flow at 2250 deg.c for 15 hr, and drawing to obtain tantalum-tungsten alloy wire with diameter of 0.6 mm.
Example 3
(1) The preparation method comprises the following steps: high purity tantalum and tungsten powders were selected, wherein the tantalum powder content was 83% and the tungsten powder content was 17%.
(2) Stirring and mixing: adding refined tantalum and tungsten powder into a ball milling bottle, and performing high-energy mixing in a ball milling mode to uniformly mix the tantalum and tungsten powder, wherein the ball milling rotating speed is 300r/min.
(3) And (5) press forming: and (3) placing the mixed powder into a mandrel die, performing top injection, and performing compression molding under the condition that the top injection pressure is 130MPa to obtain a molded blank.
(4) Sintering: sintering the formed blank in vacuum or hydrogen flow at 2250 deg.c for 18 hr, and drawing to obtain tantalum-tungsten alloy wire with diameter of 0.6 mm.
Example 4
(1) The preparation method comprises the following steps: high purity tantalum and tungsten powders were selected, wherein the tantalum powder content was 87% and the tungsten powder content was 13%.
(2) Stirring and mixing: adding refined tantalum and tungsten powder into a ball milling bottle, and performing high-energy mixing in a ball milling mode to uniformly mix the tantalum and tungsten powder, wherein the ball milling rotating speed is 350r/min.
(3) And (5) press forming: and (3) placing the mixed powder into a mandrel die, performing top injection, and performing compression molding under the condition that the top injection pressure is 170MPa to obtain a molded blank.
(4) Sintering: sintering the formed blank in vacuum or hydrogen flow at 2250 deg.c for 21 hr, and drawing to obtain tantalum-tungsten alloy wire with diameter of 0.8 mm.
Example 5
(1) The preparation method comprises the following steps: high purity tantalum and tungsten powders were selected, wherein the tantalum powder content was 90% and the tungsten powder content was 10%.
(2) Stirring and mixing: adding refined tantalum and tungsten powder into a ball milling bottle, and performing high-energy mixing in a ball milling mode to uniformly mix the tantalum and tungsten powder, wherein the ball milling rotating speed is 400r/min.
(3) And (5) press forming: and (3) placing the mixed powder into a mandrel die, performing top injection, and performing compression molding under the condition that the top injection pressure is 200MPa to obtain a molded blank.
(4) Sintering: sintering the formed blank in vacuum or hydrogen flow at 2300 deg.c for 24 hr, and drawing to obtain tantalum-tungsten alloy wire with diameter of 1.0 mm.
Table 1 examples 1-5 process conditions
In order to verify that the tantalum-tungsten alloy wire prepared by the embodiment of the invention has better strength and stability, the high-strength stretch-proof tantalum-tungsten alloy wire provided by the embodiment of the invention is illustrated by the following test examples.
Test examples
In the test example, the tantalum-tungsten alloy wires provided in examples 1-5 were subjected to mechanical strength and tensile resistance tests;
tensile strength test standard: astm b365-15; test conditions: the tensile test is carried out at normal temperature by using a universal tester, so that the load direction of the sample is vertical to the evolution direction;
flexural strength test criteria: astm f2516-20; test conditions: performing bending test at normal temperature by using a three-point bending tester, and preparing a sample meeting the standard size requirement according to the standard requirement;
fatigue strength test standard: ASTME606-12; test conditions: the method comprises the steps of carrying out tests under a certain load, wherein the load and the test temperature applied by each test are carried out according to standard rules, and the characteristics of duration, load amplitude, soft and hard deformation degree and the like maintain a certain circulation rule;
tensile test standard: continuously stretching for 10 hours;
specific detection indexes are shown in Table 2.
TABLE 2 detection index for each sample of examples 1-5
According to the table 2, the tantalum-tungsten alloy wires provided in the embodiments 1-5 of the invention have tensile strength higher than 500MPa; the bending strength is higher than 900MPa; the elastic modulus is higher than 270GPa; the tantalum-tungsten alloy wire prepared by the process has better tensile resistance, bending resistance, rigidity and stability; meanwhile, after continuous stretching for 10 hours, the tensile strength reduction rate is lower than 3 percent, and the tensile strength is extremely strong.
The foregoing has shown and described the basic principles, principal features and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the above-described embodiments, and that the above-described embodiments and descriptions are only preferred embodiments of the present invention, and are not intended to limit the invention, and that various changes and modifications may be made therein without departing from the spirit and scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims (7)

1. A high-strength stretch-proof tantalum-tungsten alloy wire is characterized in that: the tantalum-tungsten alloy wire comprises tantalum powder and tungsten powder, wherein the content of the tantalum powder is 75-90%, and the content of the tungsten powder is 10-25%.
2. The high strength stretch-proof tantalum-tungsten alloy wire according to claim 1, wherein: the diameter of the tantalum-tungsten alloy wire is between 0.1 and 1.0 mm.
3. A method for preparing the high-strength stretch-proof tantalum-tungsten alloy wire according to any one of claims 1-2, comprising the steps of:
s1, preparing raw materials: selecting high-purity tantalum and tungsten powder, and controlling the proportion of the two raw materials at the same time;
s2, stirring and mixing: adding refined tantalum and tungsten powder into a ball milling bottle, and performing high-energy mixing in a ball milling mode to uniformly mix the tantalum powder and the tungsten powder;
s3, press forming: placing the mixed powder into a mandrel die, and adopting top injection compression molding to prepare a molded blank;
s4, sintering treatment: and sintering the formed blank in vacuum or hydrogen flow, and drawing to obtain the tantalum-tungsten alloy wire after the formed blank is sintered.
4. The method for preparing the high-strength stretch-proof tantalum-tungsten alloy wire according to claim 3, wherein the method comprises the following steps: in the step S2, the ball milling rotating speed is 200-400r/min.
5. The method for preparing the high-strength stretch-proof tantalum-tungsten alloy wire according to claim 3, wherein the method comprises the following steps: in the step S3, the top injection pressure is 50-200MPa.
6. The method for preparing the high-strength stretch-proof tantalum-tungsten alloy wire according to claim 3, wherein the method comprises the following steps: in the step S4, the sintering temperature is 2200-2300 ℃.
7. The method for preparing the high-strength stretch-proof tantalum-tungsten alloy wire according to claim 3, wherein the method comprises the following steps: in the step S4, the heat treatment time is 12-24 hours.
CN202310619689.5A 2023-05-30 2023-05-30 High-strength stretch-proof tantalum-tungsten alloy wire and preparation method thereof Pending CN116607056A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202310619689.5A CN116607056A (en) 2023-05-30 2023-05-30 High-strength stretch-proof tantalum-tungsten alloy wire and preparation method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202310619689.5A CN116607056A (en) 2023-05-30 2023-05-30 High-strength stretch-proof tantalum-tungsten alloy wire and preparation method thereof

Publications (1)

Publication Number Publication Date
CN116607056A true CN116607056A (en) 2023-08-18

Family

ID=87685134

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202310619689.5A Pending CN116607056A (en) 2023-05-30 2023-05-30 High-strength stretch-proof tantalum-tungsten alloy wire and preparation method thereof

Country Status (1)

Country Link
CN (1) CN116607056A (en)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4062679A (en) * 1973-03-29 1977-12-13 Fansteel Inc. Embrittlement-resistant tantalum wire
US5918104A (en) * 1997-12-24 1999-06-29 H.C. Starck, Inc. Production of tantalum-tungsten alloys production by powder metallurgy
CN108436074A (en) * 2018-04-17 2018-08-24 中南大学 Tantalum-tungsten alloy foil preparation method and tantalum-tungsten alloy foil
CN111763838A (en) * 2020-07-09 2020-10-13 宝鸡恒业有色金属科技有限公司 Preparation process of tantalum-tungsten alloy wire
CN111869338A (en) * 2018-03-19 2020-10-30 塔克托科技有限公司 Multilayer structure for electronic devices and related manufacturing method

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4062679A (en) * 1973-03-29 1977-12-13 Fansteel Inc. Embrittlement-resistant tantalum wire
US5918104A (en) * 1997-12-24 1999-06-29 H.C. Starck, Inc. Production of tantalum-tungsten alloys production by powder metallurgy
CN111869338A (en) * 2018-03-19 2020-10-30 塔克托科技有限公司 Multilayer structure for electronic devices and related manufacturing method
CN108436074A (en) * 2018-04-17 2018-08-24 中南大学 Tantalum-tungsten alloy foil preparation method and tantalum-tungsten alloy foil
CN111763838A (en) * 2020-07-09 2020-10-13 宝鸡恒业有色金属科技有限公司 Preparation process of tantalum-tungsten alloy wire

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
刘太平等: "功能高密度材料Ta-12W金相和性能的研究", 中国核科技报告, no. 00, 31 December 1999 (1999-12-31), pages 347 - 362 *
缪强等: "《有色金属材料学》", vol. 2, 30 September 2018, 西北工业大学出版社, pages: 247 *

Similar Documents

Publication Publication Date Title
CN111593215B (en) Preparation method of high-strength plastic-matched titanium alloy Kirschner wire
CN102041402A (en) Preparation method of low-oxygen molybdenum alloy and application thereof
CN102041404A (en) Method for preparing low-oxygen titanium-zirconium-molybdenum (TZM) alloy and application
CN102049523A (en) Free-cutting water-atomized steel powder and preparation method thereof
CN102041403A (en) Preparation method of low-oxygen MHC alloy and application of low-oxygen MHC alloy
CN109277574A (en) A kind of preparation method of compressor of air conditioner swinging block
CN107619980A (en) A kind of ultra-fine grain cobalt-free hard alloy and preparation method thereof
CN106834793A (en) Add high intensity dispersion-strengthened Cu of cerium and preparation method thereof
CN113399662A (en) Preparation method of molybdenum-lanthanum alloy sintered blank and product thereof
CN109014214B (en) Preparation method of HK30 material based on MIM molding and HK30 blade
CN107745127A (en) Based on metal powder injection molded female thread machining method
CN116607056A (en) High-strength stretch-proof tantalum-tungsten alloy wire and preparation method thereof
CN113430417A (en) High-performance titanium alloy added with rare earth oxide and preparation method thereof
CN105220085A (en) A kind of high strength non-crystaline amorphous metal and its preparation method and application
CN102839309A (en) Mixing method for preparing high-strength high-tenacity molybdenum alloy
CN116334463A (en) Ultra-long high-strength ultra-fine tungsten alloy wire and preparation method thereof
CN109794606A (en) A kind of titanium alloy and preparation method thereof
CN113667903A (en) Stepped structure austenitic stainless steel, seamless pipe and preparation method and application thereof
CN109336630B (en) Support and preparation method thereof
CN112301247A (en) Method for preparing vanadium nitride from vanadium slag
CN114480943A (en) Ultralow-carbon low-cobalt martensitic steel and preparation method thereof
CN116275043A (en) MIM metal injection molding process
CN102534293A (en) High strength superfine crystalloid copper-germanium alloy and preparation method thereof
CN113102752A (en) High-performance powder metallurgy titanium metal and preparation method thereof
CN113185792A (en) Preparation method of metal modified enhanced polytetrafluoroethylene glass fiber composite material

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