US3160502A

US3160502A - Method of making beryllium billets

Info

Publication number: US3160502A
Application number: US61769A
Authority: US
Inventors: Orpheus F Quartullo
Original assignee: American Beryllium Co Inc
Current assignee: American Beryllium Co Inc
Priority date: 1960-10-10
Filing date: 1960-10-10
Publication date: 1964-12-08
Anticipated expiration: 1981-12-08

Description

1964 o. F. QUARTULLO 3,

METHOD OF MAKING BERYLLIUM BILLETS Filed 001:, 10, 1960 IN VEN TOR. ORPHEUS E QUARTULLO ATTYS.

' the beryllium.

United States Patent O can Beryllium Company, Ina, Sarasota, Fla, a corpo- This invention relates-to improved methods for making beryllium billets, ingots, or other shaped beryllium parts from beryllium powder 'and/ or chips.

The process of refining beryllium ore is .well known.

This is usually accomplished by refining the ore into pebble form by the application of heat, followed by the crushing of the pebbles into a fine powder, for example, capable ofpassing a 200 mesh screen. 7

It has been the practice heretofore to then take'the beryllium powder prepared as described and transform it into billetform by placing the powder in a carbon crucible,

followed by the placement of the crucible in a furnace wherein the crucible is heatedtotemperatures of as high as 1900 degrees Fahrenheit, and to simultaneously apply hydraulic pressure to the powder in the crucible. The entire operation has taken from '72 to 80 hours to make a -inchbillet. Not only is the process time-consuming, asfindicated, but the combination of the high temperatures and the high pressure has resulted in many crucible failures and furnace failures, for example, with.

the bottom of the furnace being pushed out. Additionally, much scrap is produced due to crucible breakage. Often the scrap produced-far exceeds the shippable billets produced, and the result is a very high per pound price on Ice tracting the air from the container during the cold compressing of the container under high pressure, heating the container and powder to a temperature of between about 1700 and 2l00 F., striking the container with high velocity dies moving at a speed of above 500 feet a sec- 0nd to reduce the volume of the container and the powder and/or chips therein to at least about 50% of its initial uncompressed volume to thereby forge the powder and/ or chips into a billet, cooling the container and billet, and stripping the container from the billet.

For a better understanding of the invention reference should be had to the accompanying drawings wherein FIG. 1 is a vertical diametric cross-sectional view illustrating a typical collapsible container filled with beryllium powder and/ or chips and inert gas and sealed;

FIG. 2 is a view similar to FIG. 1 but illustrating the container and the beryllium powder and/ or chips materially reduced in size or volume by the application of high speed striking dies thereto;

FIG. 3 is a perspective'view illustrating the billet or article as removed from the container of FIG. 2 and machined; and I It is the general objectof the present invention to avoid and overcome the foregoing and other ditliculties of and lium powerin an inert evacuated or gasrfilled collapsible containerfollowed by particularly high speed forgingof the highly heated powder to substantially instantaneously convert the beryllium powder into a forged article, such as a billet. e

of the character described and whereby the beryllium powder can be converted directly to a finished or substantially finished product of precision shape'and high physical. strength, heat resistance and durability.

' Another object of the invention is the provision of a process of the character described which ca'nbe employed 1. with beryllium powd'er,'* era mixture of beryllium powder.

and beryllium chips, or;beryllium chips. v i The foregoing objects of the invention, and other, ob-

jects which will become apparent as the description proceeds -are achieved by that method or making beryllium billets which includes the steps of filling;a 'bellows-like collapsible metal containergwiththe refined and screened beryllium powder and/or f'chips, sealing the containe "exv v Another object of the invention is to provide a process 7 FIG. 4 illustrates a 1container for making a cylinder 1 in accordwith the invention.

Referring to the drawings, the numeral 1 indicates a collapsible container, for example, made of stainless steel having a wall thickness of up to .1 inch but more usually in the neighborhood of .020 inch, a diameter of some 15 inches, and a length or height of two feet, and having a bellowsshape in cross section in the manner'illustrated. The container 1 is adapted to be filled with beryllium powder produced in known manner, as by refining the ore under heat to form pebbles, crushing the pebbles ,to fine powder, and passing the powder through a 200 mesh screen. K i

The invention is. primarily concerned with the treatment of beryllium powder, as described. However, the principles of the invention can be utilized as well. for operations upon a mixture-of beryllium powder and beryllium chips or upon beryllium chips-alone. The beryllium chips are obtained from machining or similar operations and 3 are normally broken up into powder or fine particle size before being reformed as herein set forth.

Oncethe container 1 is filled with the beryllium pow-. 'der and/or chips 2 the top of the container 1 is closed by a plate 3 of metal and the container is crimped over,

and sealed as by welding at 4"the top 3 to the container t. A similar closure may be provided at the bottom of press, to compress the container and its contents 'endwise.

Pressures of at least several hundred pounds per square "inch should be used and preferably pressures of several" thousand pounds per square inch with the 'container being supported at its sides if too much tendency to distort occurs. i

It is possible to practice the invention by sealing the 'conduit 5 of the container 1 afterallor substantially all of the air has been evacuated therefrom and the container has been cold compressed.

EflThe invention'likewise contemplates after substantially as all theair evacuated from the container, to bleed into as the container by a conduit a an inert gas, such as helium or argon. This washes out any residual air and replaces it with an inert gas whereupon conduit 5a is sealed. Vacuum is usually continuously applied by conduit 5 during this washing out operation and is continued after conduit 5a is sealed to again create a good vacuum in the container. Now conduit 5 is sealed.

Next the container prepared in the manner described, and compressed cold as heretofore set forth by about 20% to about 40% of its initial and uncompressed volume, is placed in an oven and is brought to a temperature which is relatively high, for example a temperature of at least about 1900 degrees Fahrenheit, this being a temperature comparable to that utilized in the crucible type of formation of beryllium billets. Although the indicated temperature is preferable, at least certain of the advantages of the invention are achieved at lesser temperatures, for example between about 1700 degrees Fahrenheit and about 2100 degrees Fahrenheit.

Once the container 1 and the beryllium powder and/or chips 2 therein has been brought to the elevated temperature described it is adapted to be struck with very high speed dies or plates. This can be accomplished by removing the container from the furnace and positioning it in a suitable high speed die apparatus. Such an apparatus forms the subject matter of copending patent application Serial No. 71,316, filed November 23, 1960, now Patent No. 3,115,676. 7

In accord with the method, once the container and its contents has been brought up to the desired elevated temperature it is struck in the manner illustrated in FIG. 2 in the direction shown by the arrows 6 by means of dies or plates 7 moving at very high speed, for example at speeds of over about 2000 feet per second. In one particular test in which excellent results were obtained the dies were moving at a speed of 2200 feet per second at the time that they struck the container and its contents. It is preferable in the performance of the method of the invention to utilize the very high speeds indicated, but at least certain of the advantages of the invention are obtained if the dies are moving at somewhat lesser speeds, for example 1000 feet per second, or even as low as 500 feet per second.

In any event, the container 1, and its contents of powdered or chip beryllium 2 are compressed or forged, preferably to reduce the volume of the container to about 50% of its initial uncompressed volume, the bellows-like construction of the container allowing this high-speed compressive action and the previous cold compressing action, in the manner illustrated in FIG. 2, without the container breaking or opening up. The container may be at least partially supported in dies during the high speed compressive action in the manner set forth in the aboveidentified application on the apparatus. Although it is the preferred practice of the invention to compress the powdered beryllium to at least about 50% of its initial the beryllium powder into a particularly solid and densev structure possessing even better physical solid and dense beryllium billets made in the very time-consuming and expensive manner of the priorart.

The forged and compacted billet and collapsed container are now cooled, the container is removed, andthe rough sides of the billet may be machined to provide the finished billet 22' indicated in FIG. 3.

Although the invention has been particularly illustrat ed and described in conjunction with the manufacture of that the process of the invention may also be utilized to directly form or forge beryllium parts of specificshapes i a beryllium billet, it should be specifically understood and sizes to exactly contoured patterns from forming dies, and with little or no machining thereafter being required. This is particularly true where parts such as hemispheres, saucers, plates, or the like are to be made, and wherein the container 1 can be made as a wafer for receiving the beryllium powder and/ or chips.

For example, FIG. 4 diagrammatically shows that the collapsible container 1a can be made in the form of a cylinder or tube, filled with powder and/ or chips, and the steps of the process followed for making a cylinder or tube of relatively thick walls.

While in accord with the patent statutes one best known embodiment of the invention has been illustrated and described, it is to be particularly understood that the invention is not to be limited thereto or thereby, but that its scope is set forth in the appended claims.

What is claimed is: v

1. That method of making beryllium billets and the like which includes the steps of filling a collapsible bellows-shaped metal container with beryllium powder, subjecting the container to high pressure applied in a direction to compress the container and powder up to at least 20% of its initial volume, extracting the air from the container, replacing the air with an inert gas, again evacuating the container, heating the container and powder to a temperature of between about 1700 F. and about 2100 F., striking the container while at the indicated temperature with high velocity dies moving at a speed of above 500 feet a second to reduce with extreme rapidity the volume of the container and the powder therein to at least about 50% of its initial volume to thereby forge the powder into a billet, cooling the container and billet, and stripping the container from the billet.

2. That method of making bodies of beryllium which includes. the steps of filling a collapsible container with beryllium powder, compressing the container and powder, extracting the air from the container, heating the container and powder to a temperature of above 1700 F., striking the container While the container and the powder is still at the stated temperature with high velocity dies moving at a speed of above 1000 feet a second to reduce materially the volume of the container and the powder therein to thereby forge the'powder into a body, cooling the container and body, and stripping the container from the body.

3. That method of making bodies from powdered metal which includes the steps of filling a collapsible container with the .metal powder, compressing the container with pressures of up to several thousand pounds per square inch to reduce the volume of the container by up to 40% of its initial volume, extracting the air from the container, heating the container and powder to a temperature of over 1700 F., immediately striking the container with high velocity dies moving at a speed of above'l000 feet a second to reduce further the volume of the container and the powder therein to thereby forge the powder into a body, cooling the container and body, and stripping the containor from the body.

4. That method of making beryllium billets and the like which includes the steps of filling a collapsible container with fine-mesh screened beryllium powder, sealing the container, cold compressing the container, replacing the air in the container with an inert gas, evacuating the major portion of the inert gas from the inside of the container, sealing the evacuated container, heating the container and powder to a tempertaure of over about 1700 F., striking the container and powder while still at the indicated temperature with high velocity dies to reduce further the volume of the container and the powder therein to thereby forge the powder into a billet, cooling the container and billet, and stripping the container from the billet.

5 That method of making beryllium bodies which includes the steps of filling a collapsible container with fine-mesh screened beryllium powder and chips, sealing the container, extracting the air from the container, heating the container and powder to a temperature of over about 1700? F., striking the container heated to the said temperature with high velocity dies moving at a speed of above about 2000 feet a second to reduce the 5 volume of the container and the powder therein to at least about 75% of its initial volume to thereby forge the powder into a body, cooling the container and body, and stripping the container from the body.

6. The method defined in claim 4 wherein the con- 10 ta-iner is of stainless steel and is bellows shaped.

6 7. The method defined in claim 4 wherein the container is tubular with concentric spaced walls of curved bellows-like contour parallel to each other, and the beryllium is formed as a tube.

References Cited in the file of this patent T. C. DurMond, Metal Progress, 1958, 74 (11). Pages 68-76.

Powder Metallurgy in Nuclear Engineering, pp. 57- 61, published by American Society for Metals, 1958.

Claims

1. THAT METHOD OF MAKING BERYLLIUM BILLETS AND THE LIKE WHICH INCLUDES THE STEPS OF FILLING A COLLAPSIBLE BELLOWS-SHAPED METAL CONTAINER WITH BERYLLIUM POWDER, SUBJECTING THE CONTAINER TO HIGH PRESSURE APPLIED IN A DIRECTION TO COMPRESS THE CONTAINER AND POWDER UP TO AT LEAST 20% OF ITS INITIAL VOLUME, EXTRACTING THE AIR FROM THE CONTAINER, REPLACING THE AIR WITH AN INERT GAS, AGAIN EVACUATING THE CONTAINER, HEATING THE CONTAINER AND POWDER TO A TEMPERATURE OF BETWEEN ABOUT 1700*F. AND ABOUT 2100*F., STRIKING THE CONTAINER WHILE AT THE INDICATED TEMPERATURE WITH HIGH VELOCITY DIES MOVING AT A SPEED OF ABOVE 500 FEET A SECOD TO REDUCE WITH EXTREME RAPIDITY THE VOLUME OF THE CONTAINER AND THE POWDER THEREIN TO AT LEAST ABOUT 50% OF ITS INITIAL VOLUEM TO THEREBY FORGE THE POWDER INTO A BILLET, COOLING THE CONTAINER AND BILLET, AND STRIPPING THE CONTAINER FROM THE BILLET.