SU1736682A1 - Diffusion welding arrangement - Google Patents

Abstract

The invention relates to equipment for pressure welding and can be used in the aviation and electronic industries for welding dissimilar materials with a large yield, while products of a large area can be welded. The aim of the invention is to increase the productivity and quality of welding. The essence of the invention is that the worktable through the balls rests on the rods installed in glasses filled with low-melting metal and located on the bottom of the vacuum chamber. Moreover, the vacuum system of the device is equipped with a freezing trap, the internal cavity of which is connected by pipeline with a check valve to the cavity for cooling the cups. At the same time, the freezing trap cryopanel is made with the possibility of contacting the working table. The device allows welding of products of a large area and nomenclature without retooling with minimum strains of 2 sludge. (Ls

Description

The invention relates to the production of a permanent joint by diffusion welding and can be used in the electronic and aviation industry.

A device for diffusion welding is known, comprising a vacuum chamber, a punch and a worktable with a ball bearing.

The disadvantages of the known device are the difficulty of transferring uniform pressure on the welded parts of a large area and the complexity of welding parts having a taper.

Closest to the invention is a device for diffusion welding, containing a punch located in a vacuum chamber, a working table in the form of a rotating faceplate, a heater of the products to be welded and a freezing trap placed in a vacuum system.

The disadvantages of this device are the difficulty of welding large-area products and having non-parallelism in the welding zone, as well as low productivity due to the cooling time of the products and mandrels being welded.

The purpose of the invention is to improve the quality of welding by eliminating non-parallelism in the weld zone and productivity by effectively cooling the products to be welded after welding.

The goal is achieved by the fact that a device for diffusion welding, containing a vacuum chamber with a bottom, a punch located in it and a working table in the form of a rotating faceplate, is set to VJ

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on the bottom of the vacuum chamber are cooled cups filled with low-melting metal, spring-loaded rods installed in the cups with the possibility of their ends contacting with the balls and a freezing trap with a cryopan made in the form of cylinders whose internal cavity is connected by pipeline with a check valve, with a cavity for cooling the cups.

The device (Figures 1 and 2) contains a vacuum chamber 1, a movable punch 2 and a work table 3 placed in a vacuum chamber, welded products 4, 5, spherical supports 6, rods 7. The rods rest on springs 8, which are placed in cups 9 s fusible metal (L PM). In the vacuum system of the device, a freezing trap 10 with cryopanels 11 is placed. The cooling agent is liquid nitrogen 12. Heater 13 serves to heat the products to be welded, and screen 14 is used to reduce heat flow from heater 13 to LMB. traps, LPM and welded products serves as a check valve 15. A pipe 16 connects the internal cavities of the freezing trap with the cooling cavity of glasses 9.

The device works as follows.

During the tests, Sitall CO-115 was welded to titanium through an aluminum gasket.

In the vacuum chamber 1, the welded products 4, 5 are placed on the punch 2 and the work table 3. Thermocouples (not shown) are installed on the products to be welded and at the bottom of the cups and the chamber is evacuated to a pressure of 5x1SG3 Pa, while the welded products are in the separated state . Then the heater 13 temperature of the welded products raise to 300-330 ° C, while the temperature at the bottom of the glass should be at least 50-55 ° C. Then the welded products are brought into contact so that under the action of the springs 8 the non-flatness of the welded products in the welding zone is eliminated and that the gap between the lower end of the rod and the bottom of the glass is not less than the stroke of the working table from the Welding position to the Cooling position. Position Welding is when we choose the flatness in the weld zone, and the position Cooling when the desktop touches

the ends of cryopanels freezing traps.

Next, the check valves 15 of the pipeline 16 and open in the freezing

liquid nitrogen is poured into the trap and cavity to cool the glasses. Weldable products locked in position Welding. After that, the welded products are again spaced by a distance of 20-25 mm and continue heating to a welding temperature of 500-550 ° C. Then, the products being welded are brought into contact, a pressure of 1.5 MPa is applied and isothermal aging is carried out for 15 minutes. In the process of isothermal aging, the supply of liquid nitrogen is stopped. Due to the heat from the working table, nitrogen is evaporated from the cavity to cool the glasses, LPM is melted (mp. 29.7 ° C) and under the action of

from the punch, the working table moves to the bottom of the vacuum chamber and touches the freezing cryopanels. After that, liquid nitrogen is poured into the trap with the non-return valve open.

The cooling process is reduced by

60-70% of the natural cooling time. After cooling, the product is discharged from the vacuum chamber.

For diffusion welding invention

allows welding of products of a large area and nomenclature without changeover with minimal deformation. While the use of specialized mandrels with one range of products to be welded, it is difficult to obtain high-quality joints with small deformations due to the flatness of the products being welded.

Claims (1)

Invention Formula A device for diffusion welding, containing a vacuum chamber with a bottom, a punch located in it and a working table in the form of a rotating faceplate mounted on balls, characterized in that, in order to improve welding quality and productivity, it is equipped with cooled glasses installed on the bottom of the vacuum chamber. filled with low-melting metal spring-loaded rods installed in the glasses with the possibility of their ends contacting with the balls, and freezing the TRAP with a cryopanel made in the form of cylinders, the cavity of which is connected by a pipeline with a check valve with a cavity for cooling the glasses. ,TO Editor M.Kelemes Phys. Compiled by A. Koblov Tehred M. Morgentap P. Korre-ktor I.Muska