JP2000141060A - Joint for different material of aluminum and steel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent deterioration of joining force and generation of peeling at a high temp. in welding by setting an amplitude of a wave form of a joining boundary and a ratio of amplitude and wave length in a specified range. SOLUTION: In a joint for different material subjected to explosion joining between an Al plate and a steel plate, an amplitude of a wave form of a joining boundary is >=0.3 mm, a ratio of amplitude and wave length is 1:1 to 1:12. Adjustment of the amplitude and the ratio of amplitude/wave length is done by adjusting an explosion speed of an explosive compound used in a range of 1500-5000 m/sec of a longitudinal sonic speed of Al or lower, and by controlling the quantity of the explosive compound to be used and a gap between the Al plate and the steel plate. An Al element content of the Al plate explosion-joined should be as much as possible in order to stably produce a joining boundary wave form within a specified value and is preferably >=99.0 wt.%. Further, the steel plate can be any steel if it has C element content of <=0.4 wt.%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-layer or three-layer structure in which an aluminum plate and a steel plate are explosively bonded for welding, such as a structure requiring the connection between an aluminum material and a steel material.
It relates to a dissimilar material joint composed of layers.

[0002]

2. Description of the Related Art Normally, when connecting an aluminum material and a steel material constituting a structure, a dissimilar material joint is interposed therebetween.
Aluminum and steel are connected by welding between aluminum and steel, and as such a dissimilar joint, a dissimilar joint in which an aluminum plate and a steel plate are directly explosively joined is used. However, when the temperature applied to the bonding interface of the explosion increases during welding, a problem often arises in that the bonding force is reduced or peeling off when the temperature is remarkable, so that the temperature of the bonding interface does not exceed about 450 ° C. It was necessary to devise something. On the other hand,
In 5333 "Joint of steel and aluminum", as a strong dissimilar material joint that does not cause problems such as peeling due to welding heat, a titanium plate is pre-exploded on steel as an intermediate material, and an aluminum plate is exploded on the titanium plate Disclosed dissimilar joints are disclosed. However, since expensive titanium is used for the intermediate material, the production cost is extremely high, and the range of use of such a dissimilar material joint is limited.

[0003]

DISCLOSURE OF THE INVENTION The present invention provides a low-cost welding method using no expensive titanium and has a bonding force not only when the temperature applied to the bonding interface during welding is 450 ° C. or less but also when it exceeds 450 ° C. It is an object of the present invention to provide a dissimilar material joint which does not cause a decrease or peeling.

[0004]

The present inventor has conducted various investigations and studies on dissimilar joints in which an aluminum plate and a steel plate are directly explosively joined together in order to solve the above-mentioned problems. As a result, the joint interface was heated during welding. Once linear thermal expansion coefficient of the steel, while about 13x10 ^-6 / ℃, for linear thermal expansion coefficient of aluminum is approximately 23x10 ^-6 / ℃, to produce a parallel shear stress to the bonding surface If the waveform of the joining interface is appropriately shaped, this generated shear stress can be absorbed or prevented well, and even if the temperature applied to the joining interface during welding exceeds 450 ° C., there is a problem in that the joining force is reduced and peeling is not caused. It has been found that no occurrence occurs, and the present invention has been accomplished.

[0005] That is, the present invention relates to a dissimilar material joint having a corrugated joint interface in which an aluminum plate and a steel plate are explosively bonded, wherein the corrugation has an amplitude of 0.3 mm or more;
In addition, the dissimilar material joint is characterized in that the ratio between the amplitude and the wavelength is from 1: 1 to 1:12. Hereinafter, the present invention will be described in detail. The amplitude of the explosion bonding interface waveform needs to be 0.3 mm or more, preferably 0.5 mm or more,
More preferably, it is 1 mm or more. Further, the ratio between the amplitude and the wavelength of the waveform needs to be in the range of 1: 1 to 1:12. When the ratio exceeds this range, when the ratio is small, the shear stress generated during welding cannot be effectively absorbed. On the other hand, when it is large, the joining interface is governed by a straight line without peaks and valleys, and the shear stress generated during welding cannot be prevented. A preferred range of the ratio value is 1: 1 to 1:10, and a more preferred range is 1: 1 to 1: 1.
1: 8.

Adjustment of the amplitude of the bonding interface waveform or the ratio of the amplitude to the wavelength of the explosion is performed by adjusting the explosion velocity of the explosive to be used to 1500 to 500, which is lower than the longitudinal wave sound velocity of aluminum of 6260 m / s or less.
This is achieved by adjusting the explosive speed in the range of 0 m / s and adjusting the amount of explosive used according to the explosion speed, or adjusting the gap between the aluminum plate and the steel plate. Determined by thickness combinations and dimensions and joined.

[0007] Since the elemental aluminum component of the aluminum plate to be exploded affects the generation of the bonding interface waveform, the component of the weight ratio of the elemental aluminum is large in order to stably generate the bonding interface waveform within the management specified value. That is, 99.0% or more is preferable. On the other hand, in the case of an aluminum plate in which the component of the weight ratio of elemental aluminum is less than 99.0%, the generation of the bonding interface waveform becomes unstable due to the influence of the other components Mg, Cr, Cu, etc. and the high material strength, and the bonding interface becomes unstable. In this case, it is difficult to make the waveform within the control specified value. In this case, the aluminum interface and the steel sheet having a weight ratio component of elemental aluminum of 99.0% or more are set so that the joint interface waveform is within the control specified value. Explosion, and the surface of the aluminum side has 9 weight percent component of elemental aluminum.
What is necessary is just to explode an aluminum plate of less than 9.0%.

[0008] In the steel sheet, the component of the weight ratio of elemental carbon is 0.1%.
Any steel type may be used as long as it is 4% or less. Hereinafter, an embodiment will be described.

[0009]

[Example 1] An aluminum plate JIS-H-4000- containing 99.59% by weight of elemental aluminum was used as a mixture.
A1050P thickness 16mm width 500mm length 1000m
m, the base material is steel plate JIS-G-3103-SB410
The thickness of 40 mm, the width of 400 mm, and the length of 800 mm were exploded by adjusting the explosive speed and the amount of explosive used so that the amplitude of the bonding interface waveform was 1 mm and the wavelength was 5 mm, and adjusting the gap between the aluminum plate and the steel plate. It was confirmed by microscopic observation of the joining cross section that the amplitude was 1 mm and the wavelength was 5 mm from the explosion plate, and the thickness (16 + 40) mm width 15 for welding joint was used.
Cut out 0mm length 150mm size, 10
An aluminum square rod of the same composition as the 0 mm square mixture was welded to a normal argon arc in all four rounds of fillet welding with a welding leg length of 16 mm.
This was carried out by welding. Next, a 100 mm square steel square bar having the same composition as the base material was welded to the base material side by normal electric welding in all four rounds of fillet welding with a welding leg length of 16 mm.

[0010] As a result, the temperature reached 500 ° C at the joint interface of the dissimilar material joint of the explosion-bonded plate by welding, but the aluminum partially peeled off on the joint surface, or extended from the base steel plate at the end. There was no such problem as protruding.

[0011]

EXAMPLE 2 First, an aluminum plate JIS-H containing 99.59% by weight of elemental aluminum was used as the first layer of the mixture.
-4000-A1050P 8mm thick, 500mm wide, 1000mm long, base material is steel plate JIS-G-3103-
SB410 thickness 40mm width 400mm length 800mm
The explosive was exploded by adjusting the explosive speed and amount of explosive so that the amplitude of the bonding interface waveform was 1 mm and the wavelength was 5 mm, and adjusting the gap between the first-layer composite aluminum plate and the steel plate. Furthermore, the surface of the first layer of the explosion plate on the side of the first layer of the mixture aluminum plate is a second layer of mixture aluminum plate JIS-H-4000-A5083P having a weight ratio component of 94.01% of elemental aluminum. Exploded 1000mm. The amplitude of the bonding interface waveform between the first layer of aluminum and the steel sheet is 1 m
It was confirmed by microscopic observation of the joining cross section that the m wavelength was 5 mm, and cut out with a size of thickness (8 + 8 + 40) mm width 150 mm length 150 mm for a welding joint, and a 100 mm square second layer on the second layer mixture side. An aluminum square bar having the same composition as that of the mixture was welded to a fillet with a welding leg length of 16 mm by ordinary argon arc welding in all four rounds. Then
A 100 mm square steel square bar of the same composition as the base material was welded to the base material side, and fillet welding with a welding leg length of 16 mm was performed by normal electric welding in all four rounds. The welding conditions were the same as in Example 1.

As a result, the temperature reached 500 ° C. at the joint interface of the dissimilar material joint of the explosion-bonded plate by welding. However, as in Example 1, aluminum partially peeled off on the joint surface, and the base material at the end portion. No problem of extending beyond the steel plate occurred.

[0013]

[Comparative Example 1] The amplitude of the bonding interface waveform was 1 mm and the wavelength was 15 m.
m, except for the material, dimensions,
The welding conditions were the same and the joints were evaluated by welding heat. The temperature at the joint interface of the dissimilar material joint of the explosive plate by welding also reached 500 ° C. as in Examples 1 and 2.

The results show that at the heat input stage during welding of the composite aluminum plate side, an aluminum plate having a large linear expansion coefficient is 1.5 mm5 at a joining interface temperature of 400 ° C. from the end of the base steel plate.
A phenomenon of extending and extending by about 3 mm at 00 ° C. was observed. When welding of the final base steel sheet was completed and the joining interface was visually observed, it was confirmed that 15 mm was completely removed from the end.

[0015]

[Comparative Example 2] First, as the first-layer composite material, that is, as an intermediate material,
Titanium plate JIS-H-4600-TP-270-C thickness 2mm width 450mm length 850mm, base material is steel plate J
IS-G-3103-SB410 thickness 40 mm width 40
It was exploded to a length of 0 mm and 800 mm. Furthermore, one of the explosion plates
The second-layer aluminum composite plate JIS-H-4000-A1050P 16 mm thick on the surface of the second-layer titanium composite plate side
We exploded 450mm in width and 850mm in length. Thickness (16 + 2 + 40) mm width 150mm length 1 for welding joint
A 50 mm dimension was cut out, and a 100 mm square aluminum square bar of the same composition as the second layer mixture was welded to the second layer aluminum plate side, and a fillet weld with a welding leg length of 16 mm was used for four rounds of ordinary argon arc welding. This was carried out by welding. Then, a 100 mm square steel square bar of the same composition as the base steel plate was welded to the base steel plate side by a normal electric welding in all four rounds of fillet welding with a welding leg length of 16 mm. The welding conditions were the same as in Example 1.

As a result, the temperature reached 500 ° C. at the joint interface of the dissimilar material joint of the explosion-bonded plate by welding, but the aluminum did not protrude at the end and did not peel off at all. This proved that Examples 1 and 2 of the present invention had a bonding strength equivalent to that of Comparative Example 2, that is, a conventional joint using expensive titanium as an intermediate material.

[0017]

According to the present invention, the dissimilar joint by direct explosion of aluminum and steel hardly causes peeling or decrease in bonding strength due to thermal stress. There is a remarkable effect that safety can be ensured and that it is not necessary to use expensive titanium as an intermediate material, so that it can be manufactured at low cost.

Claims (3)

[Claims] 1. A dissimilar joint having a corrugated joining interface in which an aluminum plate and a steel plate are explosively joined, wherein the amplitude of the corrugation is 0.3 mm or more, and the ratio between the amplitude and the wavelength is 1. , 1: 1 to 1:12. 2. The dissimilar material joint according to claim 1, wherein the aluminum plate has at least 99.0% of elemental aminium in a component ratio by weight. 3. An aluminum plate comprising: a first aluminum plate containing less than 99.0% of elemental aminium by weight; and 99.0% of elemental aminium by weight.
The dissimilar material joint according to claim 1, comprising two layers obtained by exploding said second aluminum plate, wherein said second aluminum plate is exploded with a steel plate.