DE2131211B2 - Composite material for welding steel and aluminum - Google Patents

Description

It was already known that numerous metals, including aluminum and steel, through Diffusion welding and explosion welding

The invention relates to a composite material that
is suitable for welding pipes, rods
or plates made of carbon steel or stainless
Steel (which is called steel here for the sake of simplicity
are designated) with tubes, rods or plates 40 to facilitate this surface in which by explosion welding of aluminum. manufactured connection material is located. It can

therefore in this way a welded connection can be achieved, which is greater than the strength mechanical action and larger heat strengthening processes can be welded together. 45 than that obtained by conventional methods In explosion welding, however, they are subject to welded joints.

connecting materials of the action of an if, however, the weld connection thus achieved

high pressure wave, so that the application of this is subjected to severe conditions, in particular process is not possible if a more gentle one is exposed to higher temperatures, so will Treatment of the parts to be welded ensures that they are unusable due to the formation of alloys, must be performed. as it loses its solidity.

In addition, explosion welding requires this especially when the known

ßen an extraordinary procedural effort and connection material for welding steel special Safety precautions. electrodes for aluminum electrolysis cells with AIu-Zur Improvement of the durability of the welding 55 minium busbars is used, as it is desirable connection, which achieved by explosion welding is worth seeing, the electrolytic manufacture of

is, you already have a lower melting metal than the metals to be welded, the one with the two base metals form an uninterrupted zone of ductile mixed crystals, between the to Welding surfaces arranged. For this purpose, steel was used for explosion welding used with aluminum nickel or copper. After the welding process has been carried out, the

Perform aluminum at high temperatures of around 300 to 350 ° C in order to increase the Allow process speed.

In addition, the properties deteriorate the well-known welded joint drastically when the temperature of the explosion welding obtained material during its application in a conventional welding process a certain

layer metal no longer as such, but exceeds 65 value. The welding must therefore

can only be carried out in the form of mixed crystals with an under adequate supervision

or both of the base metals are present. den, so that the temperature of this material is not

Ice was also known to cause explosions to exceed 450 ° C.

The same applies if the connection material used to weld stainless steel to aluminum, as in manufacturing of boilers for liquid oxygen. In this case, the deterioration in airtightness is due to the Interface between stainless steel and aluminum, which is caused by the welding heat difficult problem.

The invention is therefore based on the object of providing a connecting material, that is suitable for welding steel with aluminum using conventional welding processes and that shows sufficient heat resistance to be applied even at higher temperatures of 300 to 350 ° C to become.

It has been found that a composite panel obtained by explosive welding can be used for this purpose with a certain intermediate layer is suitable.

The subject of the invention is thus a composite material for welding steel and aluminum, that of a composite plate obtained by explosion welding with layers of steel and There is aluminum, which is characterized in that in the composite plate between the layer Steel and the layer of aluminum a layer of titanium is arranged.

With the help of the composite material according to the invention for welding steel and aluminum a higher heat resistance is achieved than with the previously known connecting materials.

The composite material of the present invention, which consists of steel, titanium and aluminum, therefore requires during its use not as precise and careful monitoring as usual joining materials for welding steel and aluminum. In addition, since it withstands higher temperatures, those obtained with it can Welded joints are exposed to higher process temperatures, so that when using it for welding the iron electrodes to aluminum busbars for aluminum electrolysis an increase in the production output of the process is possible.

For the production of the composite material according to the invention, not only carbon steel is suitable as steel, but also stainless steel. Not only pure aluminum but also aluminum alloys can be used as aluminum which do not contain magnesium can be used.

The composite material according to the invention for welding steel and aluminum does not necessarily have to be be made up of three layers, namely steel, titanium and aluminum; it is for example also possible to use a composite material consisting of five layers, such as carbon steel, stainless steel. Titanium, pure aluminum and corrosion-resistant aluminum.

The invention is illustrated by the following examples.

example 1

Having a titanium plate of the composition

H <L 0.015%,

O <; 0.20 "/ O,

N £ 0.05%>,

Fe <Ξ 0.20%,

Remainder Ti (JIS, H 4600: TP 28), a thickness of 2 mm with a carbon steel plate the composition

C = 0.19%,

Si = 0.20%,

Mn = 0.67%,

P = 0.011%,

S = 0.02%,

Remainder Fe (JIS, G 3101: SS 41),

15 mm thick was joined by conventional explosion welding, an aluminum plate was made the composition

Cu <Ξ0.05%,

Si ^ 0.25%,

Fe <: 0.40%,

Mn <Ξ 0.05%,

Zn <Ξ0.05%,

Ti <; 0.03%,

Al ^ 99.50%

(JlS, H 4101 IA ₁ P ₁ - ¹ Z ₂ H)

a thickness of 5 mm also attached by explosion welding, so that a three-layer composite board obtained from carbon steel; titanium and aluminum with a total thickness of 22 mm, a width of 400 mm and a length of 900 mm. By cutting out square Panels with a width and length of mm each made from this composite panel became a connecting material obtain. On the surface of the steel side of this composite panel was - roughly in the Middle - at right angles to one of its ends

a carbon steel rod of the composition

C ..

Si.
Mn
P ..
S ..

ReStFe (JIS, G 3101: SS 41)

= 0.19%, = 0.20%, = 0.67%, = 0.011%, = 0.02%,

with a square cross-section of 30 mm and a length of 200 mm according to a conventional one Electric welding process welded. Then on the surface of the aluminum side - about in the middle - an aluminum rod of the composition

Si
Fe
Mn
Zn

<: 0.05%,

^ 0.25%, <Ξ 0.40%, ^ 0.05%, ^ 0.05%,

Ti <: 0.03%,

Al Ξ> 99.50%

(JIS H 4161 IA ₁ B ₁ - F)

with a square section of 30 mm and a length of 200 mm at right angles to his one end welded using a conventional argon arc welding process.

As a result of this welding, the temperature of the composite materials rose and reached 500 ° C. But the interface created by explosion welding

5 6

had been welded showed no peeling and inner thickness of 2 mm wuide with a stainless

remained intact. Composition steel plate

If this entire arrangement continues for 4 hours

kept at 500 ° C, cooled and then a C <L 0.08%,

Tensile load in the axial direction of the rod subject to 5 Si <Ξ 1.00 ° / o,

the curly part of the aluminum broke, Mn ^ 2.00%,

minium rod on the composite material, but it resulted in ρ < 0.04%,

there is no change in the composite material ~. ' , "'

itself, making the superiority of the strength of the = '"'

Connection is demonstrated. io ^{Ni 8 '00 to} 10.50%,

Then a chisel was applied to the boundary surface Cr 18.00 to 20.00%,

the connection between titanium and aluminum - remainder Fe (JIS, G 4304: SUS 27)

set to forcibly remove the layers;

however, there was no sign of detachment of a thickness of 12 mm by a common explo-

at the boundary surface with the exception that the single-sion welding method is connected, and then

Hch aluminum was partially demolished. became an aluminum plate of the composition

The interface between steel and titanium became _, <0 05 »/

a subjected to the same test, but a capital ^u = '"'

Resistance to loose lots also here Si ^ 0.25%,

established. 20 Fe ^ 0.40Vo,

For comparison, on the other hand, a connection Mn <Ξ 0.05%,

dung, 50 mm square, from a composite panel ^ _n <0.05%,

cut out by welding a 5 mm. ^ n'o "? ⁰ / '

thick composite aluminum plate - '°'

Cu <0.05%,> 5 Al ^ 99.50%

Si! O, 25 · /., (JIS, H 4101: A ₁ P ₁ -V ₂ H)

^ ^E ύ 0.40%, _e j _ner thickness of 5 mm by explosion also

Mn 5Ξ 0.05%, welded to the titanium surface in order to

Zn <Ξ 0.05%, 3o a 3-layer composite plate made of stainless

Ti <0.03% steel, titanium and aluminum with an overall thickness

_Λ) --Γοο'ςηο / ' ^of 19 mm, a width of 500 mm and one

m "« a \ '\ " a Γ' ^{length of 900 mm consists} > ^to obtain.

(JIS, H 4101! A ₁ B ₁ - V ₂ H) A ring with was made _{from this composite plate}

with a 17mm thick carbon steel plate of 35 an outside diameter of 43mm, a thickness

Composition of 5 mm and a height of 19 mm cut out

^To obtain C = 019 ° / ^s * ^{'to eme} pipe joint.

_. _ _n ' _{9no /} ' With the steel side of this connection became a

~~ '"' Composition stainless steel

Mn = 0.67%, ₄ o

P = O, Ollo / o, ^C <: 0.08%,

S = 0.02Vo, ^Si ^ ¹ ^ ⁰ "' ⁰ '

Remainder Fe (JIS, G 3101: SS41) ^Mn ^ 2.00%,

P <Ξ 0.040%,

obtained by conventional explosion welding 45 ς <q q3q o / ₀

was, and a steel rod and an aluminum rod were- '"''. = ,' _nno ,

also as in the previous case under Ver ^{Nl X} ' ^{UU ms 11> υυ / o} '

this connection is welded. Cr 18.00 to 20.00%,

During welding, the temperature of the composite material rose and reached 500 ° C; a Los 50 solve, however, ^an inner diameter of 32 mm, which have been welded together by explosive welding ^{strength of} _o ⁸⁰ mm a length of 200 mm Stirnwar observed surface was attached to a part of the interface, ^with placed on end face and by butt-If this Weld the whole assembly for 1 hour at 500 ° C. An aluminum was then held, then cooled, and a draft tube of the composition

load in the axial direction of the rod subjected to Cu 5Ξ 0.05%,

was, a detachment at the explosion si <0.25%,

welded interface even at a low be p _e <040%

load determined. = '".",'

₆ Mn S 0.05%,

^{Bei iel} P ^ ² Zn 0.05%,

A titanium plate with the composition Ti <Ξ 0.03%,

H <; 0.015%, Al;> 99.50%

O ^ 0.20%, ₆ (JIS, H 4141 1A ₁ T ₁ -H)

, _M j _{t EMEM} outer diameter mm ^ N 0.05% of 40, a

Fe rg 0.20%, thickness of 3.5 mm and a length of 200 mm

Remainder Ti (JIS, H 4600: TP 28) end-to-end with the aluminum side of this connection

21 3

welded using a conventional argon welding process.

As a result of this welding, the temperature of the joint rose and reached 550 ° C; the interface, which had been connected by explosion welding showed no peeling and remained stable.

After welding a stainless steel plate and an aluminum plate, each attached to the openings of the ends of both the stainless steel pipe and the aluminum pipe for connection had been welded, and after completion of the sealing ^, was turned into a stainless steel Plate drilled a small hole and carried out the airtightness test by using a vacuum pump was evacuated. No leak was found at all and the superiority of airtightness thus proven.

When a tensile load was applied in the axial direction of this pipe, it was broken off on welded part between the aluminum pipe and the joint; the connection itself showed however, no sign of change at all. The superiority of strength was thus under Proven.

On the other hand, a pipe joint of the same size mentioned above was selected for comparison a composite plate cut out by explosion welding a stainless steel plate of the composition

C ^ 0.08Vo,

Si ^ 1.00 «/«,

Mn ^ 2.00%,

211

ρ <; o, 40 ° / o,

s <; o, o3O ° / o,

Ni 8.00 to 10.50 Vo,

Cr 18.00 to 20.00Vo,

Remainder Fe (JlS, G 4304: SUS 27)

with a thickness of 14 mm with an aluminum plate of the composition

ίο Cu ^ 0.05Vo,

Si <; O, 25Vo,

Fe <; O, 4OVo,

Mn <; O, O5Vo,

Zn <; O, O5Vo,

Ti <; O, O3Vo,

Al ^ 99.50Vo

having a thickness of 5 mm was obtained by an ordinary method, and also a stainless one Steel pipe and an aluminum pipe welded on as in the above-mentioned case. The temperature of the Compound reached 550 ° C; however, it did not become

The visible change was detected on the surface welded by explosion welding When a similar airtightness test was carried out, a slight leak was observed. If further a tensile load as in the above

mentioned case was created, the detachment took place from the connected boundary surface between see the aluminum and the stainless steel be only light load.

509 581 /:

Λ Ο7 / Ι

Claims (5)

Patent claims: 1. Verbundmateri ύ for welding steel and aluminum, which consists of a composite plate obtained by explosion welding with layers of steel and aluminum, characterized in that in the composite plate between the layer of steel carbonization of aluminum or aluminum alloys with iron alloys a better contact between the non-oxidized aluminum surface to achieve with the iron alloy that the 5 oxide layer beforehand by spraying a monomolecular Layer of a metal with a high boiling point, such as molybdenum, cobalt, nickel or titanium, was removed. Also in this case there was a direct connection between the iron alloy and and the layer of aluminum creates a layer of the aluminum alloy, since the up sprayed monomolecular metal layer by reaction with the oxygen of the oxide layer and diffusion is consumed during explosion welding. There was a need to weld steel and aluminum or aluminum alloys not only through explosion welding, but also by common, more easily applicable welding processes associate. Attempts have therefore also been made to Titanium is arranged. 2. Composite material according to claim 1, characterized in that the steel is carbon steel or stainless steel is present. 3. Composite material according to claim 1, characterized in that the steel layers of two different types of steel and / or steel alloys are present. 4. Composite material according to one of claims 1 to 3, characterized in that in 20 welding processes and a welding process in which the aluminum layer is made of pure aluminum or at the same time a special alloy treatment is carried out to use an aluminum alloy free of magnesium for this purpose. However, these methods are disadvantageous in that 5. Composite material according to one of the parts to be welded with regard to the Proverbs 1 to 4, characterized in that the 25 size are limited and the welded pro-aluminum layer from layers of two ducks have lack of strength and opposite Are sensitive to heat and shock. To improve the usual welding process, attempts have therefore been made to use aluminum and steel under Use of a special connecting material to connect using conventional welding processes. A connection material made of steel and aluminum was produced by means of explosion welding was placed between the steel and aluminum parts to be joined and both parts connected by welding to the connecting material. This method has the advantage that there is no brittle alloy layer on the contact surface between steel and aluminum, because different types of aluminum
nium alloys. and / or aluminum