JPH01249278A - Resistance diffusion joining method - Google Patents

Abstract

PURPOSE:To perform resistance diffusion joining without deteriorating strength of a joining part by inserting low melting point metal between materials to be joined and pressing it between electrodes in opposition and applying a current between both electrodes to melt and join. CONSTITUTION:The set pressure is applied to the electrode 1a by a pressure device 4 and brazing filler metal 3 such as Ni amorphous inserted between the materials 2a and 2b to be joined is pressed. The current is then applied via the brazing filler metal 3 between the electrodes 1a and 1b to melt the brazing filler metal 3 and the materials 2a and 2b to be joined are subjected to diffusion welding. At this time, as the displacement of the electrode 1a increases, the displacement of a reference plate 10 also increases but the pressure device 4 can be operated by the set pressure by controlling an inflection point where the displacement increases by a displacement gage 11 by a controller 9. By this method, the resistance diffusion with the little quantity of a deformation can be performed without deteriorating the strength of the joining part.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a resistance diffusion bonding method that utilizes resistance heating.

(Prior art) This type of conventional technology is based on the opposing electric power 11 as shown in Figure 3.
A low melting point metal 103. For example, a brazing material containing St, B, etc. is inserted and arranged, and the electrode 101 is
While the material to be joined is pressurized by applying pressure to the metal 103, power is applied to the electrodes 101a and 101b from the power source 105 to melt the low melting point metal 103 with resistance heat, thereby reducing the diffusibility of Si, B, etc. contained in the low melting point metal 103. The components are bonded by diffusion, and the temporal changes in this pressing force and heating current are shown in Figure 4. It was also constant when diffusible components were diffused.

(Problems to be Solved by the Invention) However, in the prior art as described above, both the heating current and the pressurizing force are large in heat, and there is a problem in that the deformation of the materials to be joined becomes large.

(Means and effects for solving the problem) A low melting point metal is interposed between opposing electrodes and materials to be welded, and while the materials to be welded are pressurized by the electrodes, the electrodes are In the resistance diffusion bonding method, in which the materials to be joined are joined by applying electricity through the resistive heat generated by the current application and melting the low melting point metal, the displacement of the materials to be joined is measured, and the displacement of the materials to be joined is measured. Controls the pressing force and amount of current applied to the electrode.

(Example) An example of the present invention will be described based on FIGS. 1 and 2.

FIG. 1 is a block diagram showing a resistance welding apparatus implementing the present invention. In FIG. 1, the opposing electric currents tila, lb
A Ni-based amorphous brazing material 3 is sandwiched between the materials to be joined 2a and 2b. 4 is, for example, a hydraulic pressurizing device; 5 is a power source that flows a current between the electrodes 1a and Ib; 6 is a current control device that controls the phase of the current; and 7.8 is an amplifier that amplifies the signal from the control device 9. It is.

10 is a reference plate attached to the electrode 1a, and 11 is a displacement meter for measuring the displacement of the Vi quasi-plate IO.

Next, the operation will be explained.

In response to a pressure setting signal set in the control device 9, the pressurizing device 4 applies zero-order control to pressurize the electrode 1a and pressurize the Ni-based amorphous brazing filler metal 3 sandwiched between the materials to be joined 2a and 2b. A current is applied from the power source 5 to the Ni-based amorphous brazing filler metal 3 via the electrodes 1a, lb and the materials to be joined 2a, 2b according to a current setting signal set in the device 9, and the Ni-based amorphous brazing filler metal 3 is melted due to resistance heat generation. death.

It is removed from between the materials to be joined 2a and 2b, and therefore the electrode
The displacement of a increases, and the displacement of the reference plate 10 also increases accordingly. The displacement meter II measures the displacement of the base YJ board 10 and sends a signal to the control device 9, and the control device 9 senses the inflection point where the displacement becomes large and sends a pressure setting signal to the amplifier 8. A current setting signal is sent to each amplifier 7. The amplifier 8 amplifies the pressure setting signal and operates the pressurizing device 4 with the set pressurizing force. Further, the amplifier 7 amplifies the current setting signal and sends it to the current control device 6.
commands the set cycle and current to the power supply 5, and the vL power supply energizes the electrodes la, lb and the materials to be joined 2a, 2b.

Figure 2 shows a diameter of 12 m using the resistance welding equipment shown in Figure 1.
, is a diagram showing the pressing force, current, and displacement for each process when resistance diffusion bonding is performed on a round bar of 1 s 43 G in length.

In the first step, a Ni-based amorphous brazing filler material is inserted between the round bars and cenoteng is performed, and in the second step, a pressure of 550 kg is applied and a current of 18,500 A and 17 cycles/second is applied. During this time, the electrode rises slightly due to thermal expansion of the round rod.

In the third step, the brazing material is melted and discharged from between the round bars, so that the downward displacement of the electrode suddenly increases. Here, the pressing force was set to 100 kg, and a current of 5000 A and 30 cycles/second was applied.

In the fourth step, the same current is applied while applying the same load as in the third step, and then the current is turned off and the pressurization is also stopped.

As a result of resistance diffusion bonding under the above conditions, deformation 1i
The amount of deformation was 0.51111, which was 1/7 of that of the conventional method, and the strength of the joint was equivalent to that of the conventional method.

In the embodiments described above, Ni-based amorphous brazing material was used, but equivalent results can be obtained even if BN i-2 is used.

(Effects of the Invention) As described above, according to the present invention, resistance diffusion bonding with a very small amount of deformation can be performed without reducing the strength of the bonded portion.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a resistance welding device implementing the present invention;
FIG. 2 is a diagram showing the pressing force 2 current and displacement for each process, FIG. 3 is a diagram showing the prior art, and FIG. 4 is a diagram showing changes in pressing force and current. la, lb... Electrodes 2a, 2b... Material to be joined 3... Low melting point metal 9... Control device 11...
Displacement 81 Patent Applicant Komatsu Ltd. Agent (Patent Attorney) Oka 1) Kazuyuki Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] A low melting point metal is sandwiched between opposing electrodes and materials to be joined, and current is applied through the electrodes while the materials to be joined are pressurized by the electrodes, and the resistance generated by the energization is In a resistance diffusion bonding method in which materials to be joined are joined by melting a low-melting point metal with heat generation, the displacement of the materials to be joined is measured, and the pressing force and the amount of current applied to the electrode are controlled based on the measured values. A resistance diffusion bonding method characterized by: