SU1593968A1 - Method of welding parts from heterogeneous dielectric materials - Google Patents

Abstract

The invention relates to the welding of dielectric materials and can be used to connect dielectrics with different values of electrical resistivity. The goal is to reduce the complexity and expand the technological capabilities of the method. For this, in the method of welding parts from dissimilar dielectric materials in the process of applying electrical voltage, a positive potential is applied to the part with a higher specific electrical resistance. In this case, a brief shunting of the specified part by surface electric discharge is carried out before and after exposure. Shunting of the part takes 1-2 seconds. 1 il.

Description

The invention relates to the welding of dielectric materials and can be used to connect dielectrics with various specific electrical resistance values.

The aim of the invention is to reduce the complexity and expand the technological capabilities of the method .:

The drawing shows a schematic diagram of the method of welding.

The method of welding a part of dissimilar dielectric materials consists in welding parts 1 and 2 of dielectric materials with different electrical resistivity, for example, quartz glass and sital glass. An intermediate layer 3 of aluminum is deposited on a part 1 of a material with a higher specific electrical resistivity (quartz glass), for example, by sputtering. The parts to be welded 1 and 2 are placed between the disk metal electrodes 4 and 5, drive them into contact with each other and apply an external locking compressive force. The parts are heated by the heater 6 and an electric voltage is applied to them, applying a positive potential to the part 1 with a higher electrical resistivity. In this case, at the initial moment, the part 1 is briefly bridged by the surface

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electric discharge 7, raise the voltage until discharge 7 is formed between the positive electrode 4 and the aluminum layer 3 for 1-2 s. Thereafter, the voltage is reduced and the parts are maintained at a low voltage. After holding, repeated short-term shunting of the part 1 with a larger value of electrical resistivity by surface electric discharge 7 for 1-2 s is carried out.

At the first stage of the welding process, by shunting a dielectric with a high electrical resistivity by surface short-term electrical discharge excited between an electrode having a positive potential and an aluminum gasket, electrical and thermal energy is transferred directly to the joint zone, this leads to a tight contact between welded surfaces, the formation of which hinders the development of ionization processes in the aluminum – dielectric gap. lower value of electrical resistivity, which have a negative effect in the process of subsequent exposure (the second stage), at which these surfaces are brought closer together and activated. The creation of a copying channel in the form of a short-term surface electric discharge after holding (the third stage) ensures that the energy necessary for the formation of an integral unit to be transferred to the zone of formation of the junction.

The proposed method makes it possible to weld parts in which access to the aluminum layer is limited, and does not require additional operations to create a constant copy of a duct for the welding time. The optimal duration of shunting a dielectric with a high electrical resistivity is 1-2 s. When the time of the surface discharge is less than 1 s, the amount of energy required for the processes responsible for the formation of the compound is not transferred to the welding zone (aluminum - dielectric with a lower electrical resistivity). An increase in this time over 2 s can lead to the formation of a continuous gas discharge channel between the electrodes on the surface of the parts to be welded, which will lead to their shunting and, consequently, to a decrease in the quality of the welded units.

Example. Welding of a CO 115 M grade metal with KU-1 quartz glass was carried out through an aluminum layer deposited on it. Diameter of quartz parts

glass 10 mm, and from the outer glass 20 mm and internal 4 mm. The height of all parts is 6 mm. The parts to be welded are placed between the disk metal electrodes so that a positive potential is applied to the quartz glass, and an external clamping force is applied. The parts are heated to the welding temperature by means of a voltage regulator included in a high-volt DC power source, and the voltage is raised to form a surface electrical discharge between the positive electrode and the aluminum gasket for 1-2 s (tp), no0 by which the voltage is reduced to a certain value at which the holding is performed. After holding, the short-term surface-by-discharge shunting of the part from

5 quartz glass for 1-2 s (tp).

Welding modes; welding temperature (Tsw) 400 ° С, voltage at holding (Isv) 1500 V, holding time (tea) 20 min.

Mechanical Testing

0 by tearing it off showed that the strength of the joint is greater than the strength of the materials being joined, the welded assemblies remain tight after exposure to a temperature change in the range from -60 to

5 + 90 ° C, mechanical shocks and vibrations produced by a special program.

The modes of welding and the magnitude of the mechanical strength for the detachment of the compounds obtained with a change in the time of flow of the surface electric discharge are given in the table.

Claims (1)

Claim 5 A method of welding parts made of dissimilar dielectric materials, comprising applying an intermediate layer of aluminum to a part with a higher specific electrical resistance, bringing the parts into contact with one another, heating them. the supply of electric voltage to parts and the exposure of parts under voltage, characterized in that, in order to reduce the labor intensity and expand the technological capabilities of the method, in the process of applying an electric voltage, a positive potential is applied to the part with a higher electrical resistivity value , while performing a short-term bypassing of the specified part by surface electric discharge before and after exposure, the shunting of the part is carried out within 1-2 s. with SSSis / J 7 four is / J 7 ////////// X