JPS61135498A - Plate like composite brazing filler metal - Google Patents

Abstract

PURPOSE:To obtain a good brazing state without producing a brittle alloy phase with brazing the silver solder of thicker layer with abutting to the side of a metal base metal by making the total thickness of the medium layer of IVa group element and the silver solder of thinner layer thinner than the thickness of the silver solder of thicker layer. CONSTITUTION:The silver solders 1, 3 being cladded on both faces of the medium layer 2 of IVa group element are first started to melt on heating to the brazing temp. The IVa group element of the medium layer 2 is melted into this silver solders 1, 3 and simultaneously diffused in the same quantity at almost equal sped toward the both surfaces being with both base metals. In the silver soldering of ceramics and metals the IVa group element of the medium layer 2 is preferentially diffused on the interface with the ceramics and the Ag solder component containing no IVa group element on the interface with the metal plays the role of brazing. It is necessary for a sound brazing to prevent the production of the brittle alloy of the metal and IVa group element. For this purpose the total thickness of the silver solder 1 of thinner layer and medium layer 2 is made thinner than the silver solder 3 of thicker layer.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is a plate-like composite material in which elements of the periodic table of elements IVa (Ti, Zr, Hf') are sandwiched between them and Ag solder with different thicknesses is laminated on both sides. This relates to a brazing filler metal (hereinafter simply referred to as a composite brazing filler metal).

(Prior art and its problems) In general, IVa is used for brazing ceramics and ceramics.
A composite brazing material is used in which Ag solder of the same thickness is laminated on both sides of the element.

However, when brazing ceramics and metals, if a conventional composite brazing filler metal is used, the IVa element melts into the Ag brazing material and at the same time moves toward the interface between the ceramic and metal base materials in the same amount at a uniform rate. Because it diffuses, active IVa
If the element (3) is made to have an effect on brazing at the interface with the ceramic, the metal and the element (3) react at the interface with the metal to form a brittle alloy phase, making it impossible to obtain a good bonding state.

(Object of the Invention) The present invention has been made in order to solve these problems in brazing ceramics and metals.

(Structure of the Invention) The composite brazing material of the present invention uses the element IVa as an intermediate material, and in a composite brazing material in which Ag solder with different thicknesses is laminated on both sides, the total thickness of the thinner Ag solder and the intermediate material is This is characterized in that the thickness of the Ag solder is thinner than that of the thicker Ag solder.

Generally, the reaction process of brazing with a composite brazing material having a layer of IVa element in the middle is as follows.

When heated to the brazing temperature, the Ag solder attached to both sides of the IVa element melts, and the P/A element melts into the solder at the same time at both interfaces with the base metal. They diffuse in the same amount at roughly the same speed and act on the brazing.

By the way, in brazing ceramics and metals, it is necessary to diffuse the IVa element in the intermediate layer preferentially to the interface with the ceramic, and to have an Ag brazing component that does not contain the IVa element take charge of the brazing at the interface with the metal. It is.

This is done by positioning the IVa element layer closer to the ceramic side than the metal side, so that the molten A
It has been found that this is possible by allowing the IVa element to diffuse through the solder (IVa) to reach the interface with the ceramic quickly and delaying its arrival to the metal side.

Therefore, in the present invention, the total thickness of the thinner Ag solder and the intermediate material is made thinner than the thickness of the thicker Ag solder.

Since the composite brazing material of the present invention does not contain a brittle alloy phase, it is easy to plastically process and can be finished into desired dimensions and shapes. A good state of deafness can be obtained without generation.

The thickness of the IVa element is preferably 1 to 18% by weight of the thinner Ag solder in view of brazing properties with ceramics.

Next, in order to further clarify the present invention, specific embodiments and conventional examples thereof will be described.

(Example 1) In the cross-sectional perspective view of a composite brazing material as shown in the figure, the thinner Ag brazing material 1 is 28% Ag-Cu, and the intermediate material 2 is T.
i, Ag-Cu 2B% as the thicker Ag solder 3;
A composite brazing material 4 whose tension thickness ratio is 3:1:6 is made,
This was rolled into a plate material with a thickness of 0.0711 m.

This brazing material was used to braze ceramics and Kovar in an argon atmosphere with the thicker Ag solder 3 set on the Kovar side.

As a result of cross-sectional observation of the brazed part, no brittle alloy phase was observed at the interface between Kovar and the brazing metal, and a good brazing condition was obtained.

(Example 2) In the cross-sectional perspective view of a composite brazing material as shown in the figure, the thinner Ag solder 1 is made of Ag-Cu 15%, the intermediate material 2 is Zr, and the thicker Ag solder 3 is made of Ag-Cu 15%.
%, and the tension ratio was 4:1:8. A composite brazing filler metal was prepared and rolled into a plate material having a thickness of 0.07 fi.

When brazing this brazing material with ceramics and 42% Fe-Ni, the thicker Ag brazing material 3 is made of 42% Fe-Ni.
Brazing was performed in an argon atmosphere with a centrifuge on the side.

As a result of cross-sectional observation of the brazed part, F e −N i4
No brittle alloy phase was observed at the interface between the 2% brazing metal and a good brazing state with strong joint strength.

(Conventional example) Ag-Cu with the same thickness on both sides with Ti sandwiched between them.
A composite brazing filler metal was made by laminating 2B%, and then rolled into a plate with a thickness of 0.07 m.

Using this brazing material, ceramics and Kovar were brazed in an argon atmosphere.

' As a result of cross-sectional observation of the brazed part, it was found that Ti, Fe, and Co were present at and near the interface between the brazing material and Kovar.

A brittle alloy layer consisting of Ni was formed, and the expected brazing strength could not be obtained.

(Effects of the invention) As detailed above, the composite brazing material of the present invention has sufficient plastic workability, and since the thickness ratio of the Ag brazing material laminated on both sides of the IVa element is changed, the ceramic and metal When brazing, setting the thicker side of the Ag solder on the metal side has the effect that a brittle alloy phase is not generated and a good brazing state can be obtained.

[Brief explanation of the drawing]

The figure is a cross-sectional perspective view of the composite brazing filler metal of the present invention.

Claims (1)

[Claims] In a plate-shaped brazing material in which an element of the periodic table IVa is used as an intermediate material and Ag solder with different thicknesses is laminated on both sides, the total thickness of the thinner Ag solder and the intermediate material is greater than the thickness of the thicker Ag solder. A plate-shaped composite brazing filler metal that is also thin.