DD143406A1 - METHOD FOR REMAINING METALLIC WORKSTOPS FOR DIFFUSION WELDING - Google Patents

Abstract

The invention relates to the heating of metallic Workpieces in diffusion welding. The aim is, while reducing the energy consumption in economic Vieise the heating of metallic To allow workpieces. The task, the energy supply so too control that in the immediate area of connecting Welding surfaces, the largest heat concentration takes place According to the invention solved in that to be connected in the Workpieces Sound vibrations in the form of longitudinal waves be generated, wherein the vibration system is tuned so that the oscillation belly of the longitudinal waves directly at the Welding point comes to rest and the pressure and temperature at the Welding is held in such a way until a compound of Workpieces made by diffusion «- Fig.2 -

Description

2 4 9 K ι &>*> *

Peter Wiesner

409 Halle-Neustadt, Block 66.0 / 2

Zustellungsbeyollmächtigter ^

Leit-BfN "Welding Technology" in the central institute for welding technology of the GDR 403 Halle, PSF 16

Method for heating metallic parts in diffusion welding

Field of application of the invention

The invention relates to a method for heating metallic parts in diffusion welding while supplying heat and pressure, in particular for connecting rod-shaped workpieces and bolts on plates,

Characteristic of the known technical solutions

It is known that a heat source mechanische'Schwingungen represent ₀ The energy absorption of vibrations in a material is called damping. The oscillating energy is converted into heat. Thus, it has been found in continuous vibration tests that samples within a down become red hot * Pure the effect of conversion of sound energy or vibration energy in

Heat due to damping has been termed thermoacoustic.

It has already been suggested that the thermoacoustic heat for pressure welding, resistance spot and stud welding exploit, "Here, the heating rods is effected by longitudinal waves, which are generated by piezo ~ electrical converters» $ s is still "known to be powerful and fast electrons, Laser beams, fast neutrons, plasma jets, gamma quanta, protons and electromagnetic fields in solid bodies generate elastic waves, which is already being used for ultrasonic testing.

As a heat source for the diffusion welding, the inductive heating, the resistance heating and the heating by radiation are known. The inductive heating is very time consuming, on the other hand, the equipment required for it are very expensive. For each of the workpieces to be joined, a coil must be adapted. Resistance heating, on the other hand, is very energy intensive, since the workpieces to be joined are heated over their entire surface, although the heat is needed or desired only at the junction. Heating by radiation has the power to cause the iron to strike the surface of the surface Welding parts is applied and must pass from there by heat conduction to .Welding, whereby the heating takes a very long time, Since the diffusion welding is a method for joining large-scale parts, heating by radiation is not only unfavorable, but also uneconomic,

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Object of the invention

By lowering the energy consumption in economic terms, the invention makes it possible to heat metallic workpieces during diffusion bonding.

The essence of the invention

The invention is thus based on the object to develop a method for heating metallic workpieces in diffusion welding, which is able to waive expensive equipment to control the power supply so that in the immediate area of the welding surfaces to be joined, the largest Y / särmekonzentration. The object of the invention is achieved by a method and the disadvantages described in the prior art eliminated by the fact that generated according to the invention in the workpieces sound vibrations in the form of longitudinal waves v / earth, the vibration system is tuned so that the antinode of the This can be achieved by the choice of frequency, by the length of the workpieces to be joined and by the design of the sonic injection system. Scanning energy is converted into heat in the workpieces as a result of the damping With the highest amplitude at the weld, the greatest heat is generated here. "The pressure required for diffusion welding is very low. As welding pressure, the contact pressure required for transmitting the sound energy is sufficient

 The sound can be generated by piezoelectric transducers

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and be supplied by sonotrodes the workpieces. However, it can also be generated by the action of high-energy rays, particles or waves in the workpieces themselves _β

When connecting several workpieces at the same time, the sound energy is conducted via sound conductors to the individual workpieces with the aid of a transducer or a suitable sound source, either using a central printing system or applying the pressure separately to each pair of workpieces.

Ausführungsbeisplel

The invention will be explained in more detail below with reference to an exemplary embodiment. In the accompanying drawing:

Figo 1: arranged in the vacuum chamber workpieces

Pig «2: the course of the vibrations.

The vacuum chamber 1 takes the two piezoelectric transducers 2; 3 on. The upper transducer 2 contains the vibration system for generating contact and sweat pressure. It is designed so that the resonance characteristics of the whole vibration system are not changed by the pressure generating means. The contact and welding pressure are generated pneumatically or hydraulically or the oil is supplied and discharged through the bushings 4

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In the converters 2 j 3, the electrical energy that is supplied via the cables 5> 6, converted into sound energy. Only the lower transducer 3 is actively driven. The upper transducer 2 provides a feedback and control signal. Sr prevents passage of the vibration system. Ber Schall is the workpieces 7; 8 via the sonotrodes 9; 10 supplied.

The Schwingungssystera is tuned so that the antinode of the longitudinal waves is located directly at the weld 11. ^j

Fig. 2 shows the course of the vibrations. Just a few seconds after switching on the sound energy at the weld 11, a temperature of about 1000 ⁰ C is reached. The pressure, which may be in the range of 100 to 1500 N / cm, is applied in advance. The temperature and pressure are maintained until the compound has been formed by diffusion. Depending on the type of material which is welded, then the cooling takes place either in the vacuum chamber 1 under vacuum or outside of it in air.

Claims (1)

6-21Z59® invention claim Method for heating, metallic particles in the case of diffusion soldering under the supply of heat and pressure, in particular for joining rod-shaped workpieces and bolts on plates, g e k e η η-characterized in that in the workpieces to be joined (7J 8) sound vibrations in Form xongitudinalwellen generated v / earth, wherein the vibration system is tuned so that the oscillation belly of the longitudinal waves directly to the weld (11) to lie and the pressure and the temperature at the weld (11) is held until a connection of the workpieces (7 J 8) by diffusion. Method for heating metallic workpieces in diffusion welding, with the supply of heat and pressure according to Item 1, characterized in that, when several workpieces (7, 8) are connected simultaneously, the sound energy is transmitted to the individual workpieces by means of a transducer or a suitable sound source via sound conductors ( 7 j 8) and either a central pressure system is used or the pressure is applied separately for each pair of workpieces Method for heating metallic workpieces in diffusion welding by applying heat to pressure according to items 1 and 2, characterized in that the longitudinal waves in the workpieces (7; 8) are produced by the action of powerful and fast electrons, laser beams, fast neutrons, plasma jets, gamma rays, protons and electromagnetic fields in the workpieces (7; 8) itself is generated. - For this 1 sheet drawings -