SU914216A1 - Resistance spot welding method - Google Patents

Description

The invention relates to the field of micro-welding and can be used for welding stranded conductor to thin metal films deposited on an insulating base.

A known method of welding with a double electrode, in which welding is carried out by heating the upper part [1).

The use of this method is difficult in the case of welding stranded conductor having a low melting point to a thin film with a high melting point, so that in order to heat the film due to heat transfer from the top to the temperature that provides the weld, the top should be heated to well above its own melting point. There is a splash, as a result the weld does not work.

2

There is a method of resistance spot welding, in which a metal gasket is placed between the parts made of difficult-to-weld materials with one another and is heated by squeezing with welding electrodes C21,

The use of a gasket improves the conditions of heat removal, but does not provide the possibility of mixing the molten metal and the formation of a strong welded joint.

The aim of the invention is to improve the quality of the welded joint.

This goal is achieved by the fact that according to the method of resistance spot welding, mainly one-sided, in which between parts of difficult-to-weld one with another materials have a gasket and heat when squeezed by welding electrodes, initially melt the area of the upper part between the electrodes,

then carry out the through melting of the gasket and part of the lower part, bring the electrodes together, introduce them into the melt and form an annular weld.

Fig, 1 shows the position of the welded parts, gaskets and electrodes before the passage of the welding current; FIG. 2, too, during the passage of the welding current; on 1

FIG. 3 "is the same at the moment of stopping the passage of the welding current; no Fig. 4 - moving the melted edges inside the melt; Fig. 5 squeezing the melted edges in the direction of the lower part and forming a welding joint; fig. 6, welded joint; in Fig. 7 ~ type Λ on fi 6.

For the implementation of the welding method, a gasket 3 of a material that has a satisfactory weld between the upper and the smallest part is installed on the lower part 1, which is a thin film deposited on the insulating base 2, and the upper part 4 is installed on the gasket 3 conductor. Welding electrodes 5 disposed above and pressed against the upper to - _e hoist 4 u gasket 3 to the bottom part 1.

With the passage of the welding current 1 _With 8 on the areas / between the electrodes and the most significant part of its C

Have

in accordance with Ohm’s law, passes through the section with the least resistance, i.e. on the multicore conductor 4, and on the strip 3 passes the part Ιρ, only an insignificant part C passes through the bottom part 1,

First, the upper part 4 melts, and since it is a conductor, it melts over the entire cross section between the electrodes 5 and after it is melted, the entire welding current 1 _s d passes through the gasket 3 and the lower part 1. Gasket 3 and the lower part 1 melts in the area between the electrodes 5 · Melon of the heating and melting of the gasket 3 and the parts ί of the current line envelops this section and the heating and melting section expands. Simultaneously with the through melting of the connected parts, the electrodes approach s Se · '

6 4

the metal melt of the part 4 located on the melted edge under the electrodes 5 ₅ shifts towards the center of melting and is combined with the strip melt 3 and part 2 located on the melted edges of these parts under the same electrodes 5 · Then they insert the electrodes 5 into the melt and form a welded connections. The gasket 3 and the lower part ι participate in joint melting until the cessation of current flow.

The melt of part 1 and gasket 3 under the action of surface tension forces from the center of the melt to the unheated edges of the perimeter and after cooling on these edges, an annular weld seam. The longer the current flow time! _with #, the longer the circumferential seam.

N p and me. Carried out the welding of a copper stranded conductor PD - I G) 0 ~ 0.08 to a chichrome film with a thickness of 20 μm deposited on an insulating base.

For the implementation of the welding between the film and the conductor, a nickel site with a thickness of 0.1 mm was installed. The conductor was pressed with two tungsten electrodes and passed one alternating current peloperiod obtained from a half-wave interrupter and transformed by a welding transformer with a transformation ratio of 4'140. The welding pressure was 1 kgf. “A special device was used for welding, ensuring the electrodes were moving in the opposite direction and downwards. When passing the welding current melts the conductor in the area between the electrodes and the current passed svaroch5 ny already laying and film, and since the thickness of the gasket is much greater film thicknesses, the OFA and splash not occur, and the joint was carried plev _e Leniye gasket and film.

When the strip and the film of the boundary melt, their joint melting goes beyond the width of the melted edges, and since their physical properties are close in their characteristics, they melt along the melting boundary to form an annular weld.

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914216

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The strength of the welded joint in the tearing and shear tests is equal to the strength of the conductor and was 1800 g. Destruction occurred through a conductor outside the weld zone. five

The use of the proposed method of resistance welding improves the quality of the product, since the presence of an annular seam increases the cross-sectional area of the joint, increases its strength and reduces resistance. Compression melted edges allows you to combine materials that are difficult to weld. The ability to observe the weld seam allows for visual quality control.

Claims (1)

Claim 20 The method of resistance spot welding, mostly one-sided, where before welding between parts of materials that are difficult to weld with one another, they place a metal gasket and heat it when squeezed by welding electrodes, characterized in that, in order to improve the quality of the welded joint, the section of the upper part between the electrodes is first melted, then the strip is melted the electrodes introduce them into the melt and form an annular weld seam.