CN211803817U

CN211803817U - Oxygen-insulated powder compacting die capable of being vacuumized and heated

Info

Publication number: CN211803817U
Application number: CN202020204413.2U
Authority: CN
Inventors: 王超敏; 陆磊; 蒋智梅; 张友亮
Original assignee: Institute of Applied Physics of Jiangxi Academy of Sciences
Current assignee: Institute of Applied Physics of Jiangxi Academy of Sciences
Priority date: 2020-02-25
Filing date: 2020-02-25
Publication date: 2020-10-30
Anticipated expiration: 2030-02-25

Abstract

The utility model provides an oxygen-insulated and powder embossing mold utensil of evacuation and heating, the mould includes that but the scalable corrugated metal pipe of sealed interface, help and take off stick (5) upper punch (1), lower punch (3), die (2). The upper male die is positioned above the lower male die, the upper male die faces downwards, the lower male die faces upwards, and the two male dies are opposite and positioned on the same central line; the female die is arranged at the upper part of the lower male die; the lower part of the lower convex die is provided with a gas channel (11) and is connected with an exhaust pipe (9). The telescopic metal corrugated pipe with the sealing interface is arranged at two ends of the outer sides of the upper male die and the lower male die. The telescopic metal corrugated pipe consists of a metal corrugated pipe (4) and a corrugated pipe fixing plate (7); two ends of the metal corrugated pipe are respectively fixed on the corrugated pipe fixing plate in a sealing connection mode. The utility model discloses the mould can assemble in the glove box, then accomplishes the suppression of nanometer powder metallurgy component in the atmosphere, realizes anaerobic high pressure suppression.

Description

Oxygen-insulated powder compacting die capable of being vacuumized and heated

Technical Field

The utility model relates to an oxygen-free and powder compacting die capable of vacuumizing and heating, belonging to the technical field of powder metallurgy preparation.

Background

In research and production, powder compaction is a widely used traditional material preparation method, and particularly, a compaction process of metal powder is one of subjects of the powder metallurgy disciplines.

With the development of nanotechnology, more and more powder processes tend to be nanocrystallized. Since the nano powder has an ultra-high specific surface, it is very easy to adsorb some impurities. Particularly for metal nano powder, the metal nano powder is very easy to oxidize, so that the performance of the material after pressing is reduced; some powders even self-ignite when contacting air, therefore, many nanopowders are loaded from a mold and finally pressed into blocks under anaerobic conditions, for example, the metal nanopowders are pressed to prepare the block nanocrystals and nano amorphous materials. Although anaerobic compaction can be performed in a glove box, it is limited to compaction of small samples at low pressure. For a large sample or a sample needing high-pressure pressing, a large press cannot be operated in a glove box, and due to the existence of inert gas, the pressed large sample has a plurality of pores, so that the mechanical property of the material is poor. If hot pressing sintering is required, the sintering cannot be carried out in a glove box.

Disclosure of Invention

The utility model aims at solving the problem of the preparation of powder metallurgy under the state of no oxygen or inert gas and discloses an oxygen-free powder pressing die capable of being vacuumized and heated.

The technical scheme of the utility model is as follows, a powder compacting die that can insulate oxygen and can be vacuumized and heated, including terrace die and die, characterized by that, the said die also includes the scalable corrugated metal pipe with sealed interface, helps and takes off the stick; the male die comprises an upper male die and a lower male die; the upper male die is positioned above the lower male die, the upper male die faces downwards, the lower male die faces upwards, and the two male dies are opposite and positioned on the same central line; the female die is arranged at the upper part of the lower male die; the lower part of the lower male die is provided with a gas channel and is connected with an exhaust pipe; the telescopic metal corrugated pipe with the sealing interface is arranged at two ends of the outer sides of the upper male die and the lower male die.

The telescopic metal corrugated pipe consists of a metal corrugated pipe and a corrugated pipe fixing plate; two ends of the metal corrugated pipe are respectively and hermetically connected and fixed on the corrugated pipe fixing plate; a plurality of round holes are uniformly formed in the circumferential edge of the corrugated pipe fixing plate and used for installing screws to fix the corrugated pipe fixing plate on the lower surface outside the upper male die and the upper surface outside the lower male die respectively; and a sealing ring circular groove is also arranged on the plane of the corrugated pipe fixing plate, and the sealing rings are respectively used for sealing between the corrugated pipe fixing plate and the upper convex die or the lower convex die.

The outer upper surface of the lower male die is provided with an inner exhaust hole, and the exhaust hole is positioned between the corrugated pipe and the female die column; the exhaust hole is connected with a gas channel in the lower convex die, gas is discharged out through an exhaust channel through the gas channel in the lower convex die, and an exhaust pipe with a valve is arranged on the outer exhaust channel.

The metal corrugated pipe has large folds, can be randomly stretched within the moving height range of the upper male die, and can bear the negative pressure of the die after being vacuumized; the inner diameter of the tube is larger than the outer diameter of the concave die column.

The upper male die is of a T-shaped cylindrical structure, and a raised head faces downwards; and the periphery of the outer lower surface of the upper male die is provided with uniformly distributed screw holes and circular sealing ring grooves for mounting a corrugated pipe fixing plate and a sealing ring.

The lower male die is of an inverted T-shaped cylindrical structure, and the raised head is upward; the circumference of the upper surface outside the lower male die is provided with screw holes and sealing ring circular grooves which are uniformly distributed and used for installing a corrugated pipe fixing plate and a sealing ring.

The working process of the utility model is as follows, the utility model of the pressing mould needs to install the concave mould on the lower convex mould, then the powder to be pressed is arranged in the concave mould column, and then the releasing assisting rod is placed on the powder; a sealing interface corresponding to the sealing opening of the metal corrugated pipe is arranged on the lower male die, a sealing ring is placed on the sealing interface, and then the telescopic metal corrugated pipe is sleeved outside the female die column; fixing the lower male die and the corrugated pipe fixing plate together by using bolts; and placing the upper male die into the female die column, and then fixing a corrugated pipe fixing plate at the upper part of the corrugated pipe and a surface sealing interface outside the upper male die by using bolts, wherein a sealing ring is arranged between the lower surface outside the upper male die and the corrugated pipe.

The beneficial effects of the utility model are that, the utility model discloses the mould can be assembled in the glove box, then accomplishes the suppression of nanometer powder metallurgy component in the atmosphere. The nanometer powder can be completely kept from contacting air, and oxidation and impurity adsorption are prevented. The size of the die can be enlarged, and the oxygen-free high-pressure pressing of a large sample can be realized. In addition, since vacuum can be drawn, vacuum compaction of the powder can be achieved to reduce the porosity of the bulk sample. If a high-temperature resistant sealing ring is used, the die can be heated to realize hot pressing or high-pressure sintering.

Drawings

FIG. 1 is a schematic view of the structure of a powder pressing mold which is oxygen-insulated and can be vacuumized and heated according to the present invention;

FIG. 2 is a schematic structural view of a flexible metal bellows with a sealing interface;

in the figure, 1 is an upper male die; 2, a female die; 3 is a lower male die; 4 is a metal corrugated pipe; 5 is a stripping-assisting rod; 6 is nano powder; 7 is a corrugated pipe fixing plate; 8 is a valve; 9 is an exhaust pipe; 10 is an air extraction opening; 11 is a gas channel; 12 is an exhaust hole; and 13 is a bolt hole.

Detailed Description

The specific embodiment of the present invention is shown in fig. 1.

A female die 2 is arranged on a lower male die 3 in a glove box; the metal nano powder 6 which is not contacted with air and is subjected to anaerobic ball milling is filled in the female die 2; putting a stripping-assisting rod 5 on the powder in the female die 2; a sealing ring penetrates through the female die 2 and is placed on a circular groove sealing interface on the upper plane outside the lower male die 3; sleeving the telescopic corrugated pipe outside the female die, and fixing the corrugated pipe fixing plate 7 and the lower male die 3 together by using bolts; a sealing ring is arranged on a circular groove sealing interface on a corrugated pipe fixing plate 7 at the upper end of the metal corrugated pipe; putting the pressing rod of the upper male die 1 into the female die column; the sealing interface of the corrugated pipe fixing plate 7 and the upper male die 1 is well matched and fixed by bolts; taking the die out of the glove box, and heating the die on a heatable flat-plate tablet press; connecting the exhaust pipe 9 with a vacuum pump, and opening the valve 8 to exhaust; pumping for a certain time, pressing by using a tablet press, and then contracting the metal corrugated pipe 4; the pressure is removed after the pressure is maintained for a certain time, and the metal corrugated pipe 4 can drive the upper male die 1 to rise back under the action of the tension because the pressure rod of the upper male die 1 is not contacted with the sample; taking down the cooled pressing die; firstly unscrewing the bolt for connecting the upper male die 1 with the corrugated pipe fixing plate 7, and taking down the upper male die 1; then, the bolt connected with the corrugated pipe fixing plate 7 on the lower male die 3 is unscrewed, and the telescopic corrugated pipe is taken down; and (4) separating the female die 2, taking out the sheet sample, and pressing to obtain the block nano material.

Claims

1. An oxygen-insulated powder compacting die capable of being vacuumized and heated comprises a male die and a female die, and is characterized by further comprising a telescopic metal corrugated pipe with a sealing interface and a stripping-assisting rod; the male die comprises an upper male die and a lower male die; the upper male die is positioned above the lower male die, the upper male die faces downwards, the lower male die faces upwards, and the two male dies are opposite and positioned on the same central line; the female die is arranged at the upper part of the lower male die; the lower part of the lower male die is provided with a gas channel and is connected with an exhaust pipe; the telescopic metal corrugated pipe with the sealing interface is arranged at two ends of the outer sides of the upper male die and the lower male die.

2. The oxygen-insulated, evacuable and heatable powder compaction mold of claim 1, wherein the collapsible metal bellows is comprised of a metal bellows and a bellows retaining plate; two ends of the metal corrugated pipe are respectively and hermetically connected and fixed on the corrugated pipe fixing plate; a plurality of round holes are uniformly formed in the circumferential edge of the corrugated pipe fixing plate and used for installing screws to fix the corrugated pipe fixing plate on the lower surface outside the upper male die and the upper surface outside the lower male die respectively; and a sealing ring circular groove is also arranged on the plane of the corrugated pipe fixing plate, and the sealing rings are respectively used for sealing between the corrugated pipe fixing plate and the upper convex die or the lower convex die.

3. The oxygen-insulated, evacuable and heatable powder compaction tool of claim 1, wherein the outer upper surface of the lower punch is provided with internal vent holes positioned between the bellows and the die post; the exhaust hole is connected with a gas channel in the lower convex die, gas is discharged out through an exhaust channel through the gas channel in the lower convex die, and an exhaust pipe with a valve is arranged on the outer exhaust channel.

4. The oxygen-insulated, evacuable and heatable powder compaction mold of claim 1, wherein the metal bellows has corrugations, can be freely extended and retracted within the range of the moving height of the upper punch, and can withstand the negative pressure after the mold is evacuated; the inner diameter of the tube is larger than the outer diameter of the concave die column.

5. The oxygen-insulated, evacuable and heatable powder compaction tool of claim 1, wherein the upper punch has a t-shaped cylindrical configuration with a nose facing downward; and the periphery of the outer lower surface of the upper male die is provided with uniformly distributed screw holes and circular sealing ring grooves for mounting a corrugated pipe fixing plate and a sealing ring.

6. The oxygen-insulated, evacuable and heatable powder compaction tool of claim 1, wherein the lower punch has an inverted t-shaped cylindrical configuration with the nose facing upward; the circumference of the upper surface outside the lower male die is provided with screw holes and sealing ring circular grooves which are uniformly distributed and used for installing a corrugated pipe fixing plate and a sealing ring.