JPH07116736A - Method and device for forming substantially flat sheet-like titanium-aluminum material into structural member - Google Patents

Abstract

PURPOSE: To make processing of a hard-to-process material easy by executing processing by heating only an area to be bended of a sheet at a specific temperature. CONSTITUTION: The area to be processed of a titanium aluminum material is positioned on a lower die 120. A heater 206 is positioned on the area to be processed and is heated at a previously specified temperature of 600 deg.F or lower for a predetermined time. After the completion of heating, the heater 206 is pivoted, is removed form a processed part, an upper die 110 is lowered and the material is bent between the upper die and the lower die 120. Since a small region to be processed is heated, a higher molding temperature than in the conventional practice is available, this small region has enough ductility to be plastically deformed and the hard-to-molding titanium aluminum material is easily bent.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for forming titanium alloy materials, and more particularly, forming titanium aluminum materials using conventional sheet metal forming equipment and tools to produce structural members, and The present invention relates to a method of performing localized heating only on a workpiece.

[0002]

BACKGROUND OF THE INVENTION In the classification of intermetallic compounds, titanium aluminum materials have been the most useful in designing structures that require high specific strength. Although unique in their classification of titanium alloy compositions, titanium aluminum materials, like the more typical titanium alloys, contain tin, zirconium,
One or more alloying additive elements such as molybdenum, vanadium, silicon, chromium, manganese and iron may be added.
Titanium aluminum materials have particular application in the field of aircraft and spacecraft design.

While there are several important end uses for titanium aluminum materials, various difficulties remain in the modification of these materials to obtain the final desired useful shape. There is. One of the most frequently encountered obstacles is the inability to manipulate these materials, which is well known to be that titanium aluminum is relatively friable and not easy to form using conventional techniques at or near room temperature. Because it is becoming.

One recent approach, which has been found to be broadly useful in constructing structural members from such materials, is to form superplasticity, in the process of which superplastic materials such as titanium alloys or aluminum are used. Alloys) are generally about 1700 ° F to about 1900 ° F
Heated to a molding temperature in the range of, and then plastically "flowing" the metal into or into the die,
Formed in a die using positive or negative pressure on one side of the metal.

While forming superplasticity has many advantages, the process has drawbacks. For example, special equipment with a controlled environment within the heating and molding equipment, very high molding temperatures (from about 1700 ° F to about 190 ° F).
Applications of 0 ° F.) and specially designed tools for handling materials and equipment during heating and until completely cooled are required. in addition,
The heating and cooling aspects of the process occur over a long period of time and require the assistance of a uniquely designed tool that has an appropriate thermal coefficient to accommodate high forming temperatures. For these reasons, and due to the fact that this process requires heat treatment not only for the entire work piece but also for the heating and forming equipment, the cost and time involved are reduced and the efficiency is the same. Alternatively, numerous efforts have been made to find alternative techniques and / or devices that achieve similar end results.

[0006]

OBJECTS AND SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to facilitate the use of conventional sheet metal forming equipment,
It is an object of the present invention to provide a novel method for forming structures from intermetallic compounds such as titanium alloys while simultaneously overcoming all the deficiencies and drawbacks of other similar forming methods.

Another object of the invention is the machining of intermetallic compounds in which localized heating of a predetermined part of the workpiece to be molded is used to overcome the frangible structure of the material at room temperature. It is an object of the present invention to provide a new molding method for manufacturing a structural member from a product.

Yet another object of the present invention is to apply heat to a predetermined area of the workpiece prior to the desired deformation of the predetermined area of the workpiece by conventional sheet metal forming equipment. It is an object of the present invention to provide a device that enables the practice of the novel method of the present invention.

These and other objects have been achieved in accordance with the teachings of the present invention by applying to a small area of a workpiece of material that is sufficiently heated to plastically deform an intermetallic compound and then conventional sheet metal forming. An operation for deforming a workpiece is performed using the device. Since the present invention uses a higher forming temperature than before to heat a small region of an intermetallic workpiece, the small region is sufficiently ductile to allow the plastic deformation necessary for the forming operation. .

[0010]

DETAILED DESCRIPTION The present invention includes a method of forming a titanium alloy material as an intermetallic compound at elevated temperatures and in combination with conventional tools such as press brakes, stretch-wrap machines, punch presses, jog ring presses and the like. It is intended to make structural members using conventional sheet metal forming equipment. The process involves heating a small portion of the work piece to a temperature at which the material retains sufficient ductility to undergo the desired deformation. Titanium aluminum alloy α2
For the (Ti ₃ Al) system, temperatures in the range of 400 ° F. to 600 ° F. have been experimentally specified. Heat is provided using a heating device that is fixed to conventional molding equipment. The present invention is
It is contemplated to improve upon conventional molding equipment such that the heating equipment may be moved away from or closer to accessibility with the small portion of the workpiece being deformed. The present invention contemplates applying heat to only a small portion of the workpiece to be manipulated. The process of the present invention therefore does not require heating of the forming tool.

FIG. 1 illustrates one embodiment of a conventional sheet metal forming machine, commonly known as a press brake, which forming machine is modified to provide the localized heating capability required to carry out the process of the present invention. Has been done.

As shown, the press brake machine 10
0 is a vertically movable press brake die 110
And a fixed press brake die 120 below. Since the upper die and the lower die are vertically aligned, the convex molding surface 112 of the upper die overlaps the concave molding surface 122 of the lower die. Typically, the convex forming surface of the upper die conforms topographically to the concave forming surface of the lower die. A heater assembly 200 is attached to the upper press brake die, which is the pivot 20.
A pivotally mounted at 4 on an upper die to move between a first position in which the arms are arranged substantially vertically and a second position in which the arms are arranged substantially horizontally. Includes arm 200. The heater 206 is held at the end of an arm that is placed opposite the end that is pivotally mounted. A plurality of quartz lamp heating elements 208 are mounted within the casing of heater 206. A thermocouple 300 is positioned under the workpiece at a position opposite the lower die (eg, substantially centered on the concave lower die forming surface 122, as shown in FIG. 1).

In carrying out the method according to the invention, a support base 13 on which a work piece in the form of a titanium aluminum material is placed immediately upstream of the lower die 120 of the press brake.
It is placed on the 0 and is fed forward through the lower die. At each of the predetermined positions at which the sheet of metal is to be flexed and deformed between the upper die and the lower die, the predetermined sheet position is located at the top of the concave molding surface of the lower die. The heater assembly is then pivoted downwardly from its second position to the first position so that the heater 206 is positioned just above the predetermined position of the seat. The heating element is then activated for a period of time to obtain a predetermined temperature suitable for the deformation to occur, the thickness of the material to be molded and the physical properties that the final product should possess. After reaching this predetermined temperature, the heating element is deactivated and the heater assembly is moved from its first position to the second position.
The heated area of the seat at the predetermined position is swiveled back to the position of the upper and lower dies of the press brake (i.e. upper die to lower die). Down and into deforming engagement with the heated area of the sheet). The sheet is then advanced in the forward direction by means of this press brake machine by a distance corresponding to the position where the deformation of the next sheet should take place.

The steps of this process are repeated until the sheet exhibits the desired shape. An example of a structural member obtained according to the steps of the inventive process similar to that described above is shown in FIG.

The present invention contemplates performing all process steps on manual and automated molding machines. In the latter case, one or more molding machines are controllable by computer hardware and software, which allows several sheets of intermetallic compound to be molded on one molding machine at a time. make it easier.

While certain representative embodiments and their details have been set forth for the purpose of illustrating the invention, various changes and modifications may be made without departing from the spirit and scope of the invention. Will be apparent to those skilled in the art.

[Brief description of drawings]

1 is a schematic illustration of a press brake molder modified to include the heating equipment necessary to carry out the heating steps of the method of the present invention.

FIG. 2 illustrates an intermetallic compound workpiece formed in accordance with the teachings of the method of the present invention.

[Explanation of symbols]

 100 Press Brake Molding Machine 110 Upper Press Brake Die 120 Lower Press Brake Die 200 Support Arm 206 Heater

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Peter Lydia, W3031 Hundred and Nineth Street, Englewood, California, 90303, United States, 3555

Claims (4)

[Claims] 1. A method for deforming a substantially flat sheet of titanium-aluminum material into a structural member using a press brake type molding machine, wherein a region of said sheet of material is where deformation is to occur. Locating, and a predetermined time for the one region in the locating,
Heating to a temperature of 00 ° F. or less; said heating by pressing an upper die associated with said press brake molder against said region towards a lower die associated with said press brake molder. Deforming the formed region into a desired shape, whereby the substantially flat sheet-like material is transformed into a non-planar structural member. 2. A structural member formed by the method of claim 1. 3. A forming apparatus for deforming a substantially flat sheet of titanium-aluminum material including an upper forming element and a lower forming element, for heating only the area of the sheet where the deformation is to occur. Means and means for interacting with the sheet to displace the heated region but not to penetrate so as to move both the upper and lower forming elements of the forming apparatus; and a new sheet for the forming means. Means for moving the sheet-like material a predetermined distance from the upper and lower forming elements to provide an area; the heating step so that the sheet is transformed into a stepped structural member; Forming means for repeating at least alternating movement steps. 4. A method for forming a structural member from a substantially flat sheet titanium aluminum material using a press brake type molding machine that includes an upper forming element and a lower forming element, the method comprising: Positioning the sheet-like material relative to the forming element of the forming machine to provide it to the forming element of the forming machine; heating the small region to a temperature of 600 ° F. or less; A step of moving one of the upper molding element and the lower molding element of the press brake type molding machine toward the other so as to perform non-fitting bending deformation in the small area, and repeating the positioning, heating, and moving steps at least once again. And transforming the sheet-like material into a structural member.