JPS5832032B2 - Brazing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sound brazing method free from brazing defects.

Fig. 1 is an explanatory diagram of a conventional brazing method, and Fig. 1a is a transparent plan view showing the brazing state through the brazing material member on the upper surface. FIG. 1C is a sectional view taken along the line CC in FIG. 1A, and FIG. 1D is a transparent plan view showing the completed state of attaching.

That is, the conventional brazing method was performed as follows.

(1) A brazing coating material 2 such as flux that facilitates brazing is applied to the entire surface of the gap between the first and second brazing material members 1 and 2 to be surface-joined.

(2) After that, the brazing material 4 is applied to the first and second covering brazing material members 1,
2 to the mutual gap between the two.

In such a conventional brazing method, FIG. When the brazing metal 4 is supplied from one end surface of the first and second brazing metal members 1 and 2 as shown by the arrow A shown in FIG. From the center between 1°2,
The brazing material 4 expands quickly at the peripheral edge.

For this reason, as shown in FIG. 1d, gas such as air is left behind in the portion B between the first and second brazing filler metal members 1 and 2, making it impossible for the brazing filler metal 4 to expand into that portion. , voids and other brazing defects occur.

This is because the rate at which the brazing filler metal 4 spreads between the first and second brazing filler metal members 1 and 2 is faster than the rate at which the brazing filler metal 4 spreads due to capillary action in the gap between the first and second brazing filler metal members 1 and 2. This is thought to occur because the rate of expansion at the peripheral edge between the two is faster.

This invention has been made in view of the drawbacks of the prior art.

The present invention will be explained below with reference to the drawings. FIG. 2 is an explanatory diagram of the brazing method according to the present invention, and FIG. Figure 2C is a side view of Figure a;
2 is a sectional view taken along line C-C in FIG. FIG.

The brazing method according to the present invention is performed as follows.

(1) As shown in FIG. 2a, the first and second covering members 1 and 2 facing each other in the gap between them are joined face-to-face.
A brazing coating material 3 such as a known flux is applied to the center part excluding the side edges to facilitate brazing.

(2) Place the brazing filler metal 4 in the first
It is supplied from one end of the second covering wax member 1, 2 other than the side end and expanded along the wax coating material 3.

(3) As shown by the arrow E in FIG. 2d, a wax coating material 3 is applied to two opposing ends of the gap between the first and second soldering members 1 and 2.

(4) When the brazing material 4 is supplied to the two opposing ends of the gap between the first and second soldering members 1 and 2 as shown by the arrow F in FIG. 2d, as shown in FIG. Sound brazing without voids as shown in e is completed.

That is, in this method, the first and second covering wax members 1,
At the periphery of the mutual gap between the first and second covering solder members 1 and 2, in order to prevent the solder material 4 from expanding faster than the expansion of the solder material 4 in the central part due to capillary action, At first, the brazing material 3 is not applied to the second side end portion, but is applied only to the central portion, and the brazing material 4 is first supplied only to the central portion.

As a result, the brazing material 3 is not applied at the two end portions, so the brazing material 4 is not expanded and the brazing material 4 is completely supplied at the center.

Thereafter, several coats of brazing material 3 are applied to the second end, and then a brazing material 4 is supplied to complete sound brazing as shown in FIG. 2e.

Note that the width from the end of the second side end portion depends on the viscosity of the wax coating material 3, but as shown in FIG. Covering wax member 1
A range of 1 to 7 mrn from the edge of is good.

Also, the second covering member 2 is better than the first covering member 1.
1 from the end of the second covering wax member 2.
~7rnm, and furthermore, if the widths of the first and second covering solder members 1 and 2 are equal, the width is 1~7mm from the end of both.
Needless to say, it is within the range of

As described above, according to the present invention, sound brazing without any brazing defects can be performed.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of the conventional brazing method, and Fig. 1a is a transparent plan view showing the brazing state through the covering brazing member on the upper surface. FIG. 1C is a sectional view taken along the line CC in FIG. 1A, and FIG. 1D is a transparent plan view showing the completed state of brazing. FIG. 2 is an explanatory diagram of the brazing method according to the present invention, and FIG. FIG. 2C is a sectional view taken along line CC in FIG. 2A, and FIG. FIG. 2e is a transparent plan view showing a state in which brazing is completed. In the figures, corresponding parts in each figure are given corresponding symbols, 1 and 2 are the first and second covering parts, 3 is the wax coating material, 4 is the brazing material, and D is the 2nd side. This is the end.

Claims (1)

[Scope of Claims] 1. A step of applying a wax coating material to a central portion of first and second covering brazing materials that are surface-joined, excluding at least two opposing side edges; A step of supplying a brazing material to the central portion coated with the coating material, and an opening J other than the central portion.
The method is characterized by comprising a step of applying a brazing material between the first and second brazing material members, and a step of supplying the brazing material to a portion other than the central portion to which the brazing material is applied. brazing method. 2. The brazing method according to claim 1, wherein the two side edges are each within a range of 1 to 7 mm from both side edges.