LU83262A1 - PROCESS AND INSTALLATION FOR THE MANUFACTURE OF AN ELONGATED ALUMINUM PRODUCT - Google Patents

Description

BL-Z117 / EM / BM

8Ï ™ 0 ^ CbRAND-DUCHY OF LUXEMBOURG

..... sf ...... 4 ...... g "of the Minister for the Economy and the Middle Classes

Title issued: ........................................ Intellectual Property Service

ψρ0 LUXEMBOURG

Patent Application I. Application

Mr Leo CLOOSTERMANS-HUWAERT, Sof te Fiermestraat 12.9680 Maarkedalf (i) Belgium represented by E.Meyers & E, Freylingers Ing. own advice. ind., 46 rum (2) from Cimetières Luxembourg, acting as mandataries file (s) this ...... twenty-seven March nineteen hundred eighty one ............ .............. (3) at,. ± „....................... hours, at the Ministry of Economy and the Middle Classes, in Luxembourg: i 1.1¾ this request for obtaining a patent of invention concerning: ..................... ... (4) aluminum ”2. the delegation of power, dated ....... Mga ^ Üdxi'l ..................... ...... on March 26, 298.1 _______________ 3. the description in the ....... French language ......................... ......... of the invention in two copies; 4 ................. drawing boards, in two copies; 5. the receipt of the taxes paid to the Luxembourg Registration Office, the MmtzMV ±.! ^ ÂMl..muf ..... Qent .... ^ tï ^., Ning ± ...] m .. .................................................. ..........................................

declares (s) by assuming responsibility for this declaration, that the inventor (s) is (are): te, applicant (5) claims (s) for the above patent application the priority of one (of ) request (s) from (®) ......................................... .................................................. ... filed in (7) ....................................... .................................................. ...................................

on ................. r ™ .............................. .................................................. .................................................. .................................................. ................................................ (8 ) in the name of ........ ~ ..................................... .................................................. .............................. (9) elect (elect) for him / her and, if appointed, for his / her proxy , in Luxembourg ...................................

^ Ç ... £ ue du Cimetière * Luxembourg ___________________________________________________________________________________________ (10) request) the issue of a patent of invention for the subject described and represented in the abovementioned appendices, - with deferment of this issue to .dixrrJiU.it · ____________________month. (11)

The ^. & S proxies "jl Deposit Minutes

The aforementioned patent application has been filed with the Ministry of the Economy and the Middle Classes, Intellectual Property Service in Luxembourg, on date i: 2? March 1981 "00 Pr.l <| made at .. — ................... hours / ^ ^ V \ of Economy and Middle Classes, 11; # .¾ / ρ · 4 · / J, A 68007 ___ / _ ► *

. BL-3117 / EM / BM

\

PATENT

Method and installation for manufacturing an elongated aluminum product; Leo Cloostermans-Huwaert

Hof te Fiennestraat 12 B - 9680 Maarkedal b ♦ PROCESS AND INSTALLATION FOR THE MANUFACTURE OF AN ELONGATED ALUMINUM PRODUCT · Κ · 8Ι · "9Ι" Β "" Β "βΙΙ £ 3" Ι && "8" β "Β98 & 8> 9 = Βΐ388Β3888Β38Κ8 “Β The invention relates to a process for manufacturing an elongated aluminum product, the process comprising a continuous casting of a casting bar followed by continuous rolling. Far elongated product, we mean any product, such as a wire, a strip or a profile, having an order of magnitude length dimension much larger than the two dimensions perpendicular to this length, regardless of the shape of the section perpendicular to the length, square, rectangular, round, trapezoidal or other. These are the products that are sometimes called "infinite" length products.

However, continuous casting has a drawback which is particularly felt during the ensuing rolling. It is known that continuous casting produces porosities due to the uneven cooling of the walls of the groove in which the aluminum solidifies to form said casting bar. We try to eliminate this porosity by rolling with a large reduction to achieve a compression sufficient to close the pores, but this compression produces internal tensions which are likely to produce cracks, especially at the places where concentrates of the brittle eutectic phases have gathered. . This is the reason why an attempt has been made to find a solution to this problem by seeking an equal greater cooling of the walls of the solidification groove, but the practical solutions in this direction give the result of the greatest crowding of the eutectic phase at the surface, which produces cracks in subsequent rolling. Conversely, the possible solutions to avoid, during solidification, J concentrations of the eutectic phases in order to avoid cracks of 2.

rolling, are found to be of the type which does not allow the elimination of the porosities of the metal in solidification. The problem of obtaining better quality of the rolled product from a casting bar therefore remains unresolved.

The method according to the invention is characterized in that, between continuous casting and rolling, said casting bar is subjected to continuous extrusion.

It should be noted that extrusion, as it is known to date for forming elongated profiles from a cast block, requires preparation for homogenization and removal, mechanically, of the eutectic concentrations. to the surface in order to obtain a sufficiently economical exit speed. However, a continuous casting bar according to the methods known to date, eg casting wheel, has a much smaller heterogeneity than a cast block, and it has appeared that it can be processed directly by extrusion, in omitting the conventional preparation, at a speed sufficient to accommodate the bar emerging from the casting wheel at its normal economic speed. Consequently, continuous extrusion at the outlet of continuous casting appears to be possible at normal economic speeds. And it is in this extrusion that the metal, by the interaction of heat and pressure, is pushed very far in the field of plastic deformation, so as to destroy the heterogeneous porous dendritic structure with its concentrates of eutectic, and the structure obtained is similar to a homogenized structure after hot rolling.

An installation for the use of the present invention will therefore comprise, arranged from upstream to downstream: a continuous casting installation of a casting bar, a continuous extrusion press, and a continuous rolling mill. The continuous casting installation h will preferably be a continuous casting wheel.

> 3.

The process remains very economical, since it is a continuous process, starting from the molten metal, without having to reheat the metal after cooling necessary for some intermediate operation of preparation for extrusion. For the extrusion, the heat inherent in the solidified metal is used, without substantial heating, although intermediate heating between the outlet of the continuous casting and the entry into the extrusion instrument can be applied to obtain an ideal temperature. input depending on the alloy, dimensions used and other parameters% of the extrusion system.

A very great advantage of the invention resides in the fact that the cross section of the extruded product can be chosen freely, that is to say that the initial shape for the subsequent rolling can be chosen. The process is therefore very universal in terms of the geometrical shape of the finished product, and can be applied especially for the manufacture of flat strips. The extrusion orifice will then have the shape of a flat rectangle, that is to say whose length is more than twice the width.

The invention will be explained below using a few drawings, given by way of example and where:

Figure “1 shows a view of the extrusion instrument preferably used in the invention.

Figure 2 shows a view of the casting wheel used in the invention.

Figure 3 shows a section of the rim of the casting wheel, along the line AA in Figure 2.

Continuous extrusion, given by way of example, will be carried out by the process called "conform" and explained in detail in US patents 3,765 »216 and US 4 * 101,253. This process is shown in Figure 1. L he apparatus used in this system comprises a friction wheel 1 of 450 mm in diameter and rotating at a speed of approximately 55 rpm per minute. The circumference of this wheel has a J slot 2 which is covered, at an angle fX of the circumference,

l I

4.

of a closing part 3 so as to form a groove 4 which ends in an extrusion orifice 5 · The casting bar 6 is directed · tangentially to the impeller and in the direction of the arrow 7, towards the entry of the extrusion groove * The friction of the wheel against the casting bar produces heating and generates a pressure inside the groove which results in the aluminum being pushed outward through the orifice 5 »And in the direction of the arrow 8y in the form of an elongated product, the cross section of which will have the shape of the orifice 5 · This process will be referred to below as" friction extrusion ".

We can for example form an alloy casting bar 6

Al-Mg-Siy by casting on a casting wheel known in the art and producing a bar having a section of 2.100 mm and coming out

at a speed of 12 m per minute and at a temperature of 500 * C

about. This bar is directed immediately towards the entry of the friction wheel 1y where it is extruded and where the extruded metal 2 has a cross section of 1000 mm. The metal is then rolled with a reduction of 20 # per step up to a diameter of 9.5 mm ·

It is preferable to form a casting bar with as little heterogeneity and porosity as possible. One way to achieve this goal may be the use of a continuous casting wheel 11 (Fig. 2 and 5) having a rim with a groove 12 on its circumference, which is covered for the most part by a metal band Bans end 13 so as to form a solidification groove 14 * This strip runs, while being guided on the wheels 13, 16, 17 and 18, at the same linear speed (in the direction of arrow 19) as the linear speed of the circumference of the wheel. The liquid metal is introduced through the nozzle 20, and the solidified bar 21 exits in the direction of the arrow 22. The inner and lateral surface of the rim is cooled by water jets, leaving a number of orifices arranged in the form of a circular arc 23 inside the casting wheel, as shown in detail in F ............

5 · ¥ is also cooled by water jets arranged in an arc 24 and 25 * as well known in the art of continuous casting. With equal refrigeration on the rim side and on the strip side, the latter side cools more quickly since the strip, which must be flexible, is thinner. This is how porosities are formed due to uneven refrigeration. This is the reason why the refrigeration arc 24 - 25 of the circumference, on the side of the strip, is delayed by an angle β with respect to the refrigeration arc 23 on the side of the rim, in order to obtain a more balanced refrigeration This delay angle can be adjusted by movement, in the direction of the arrows 26, of the half-arc 24, with respect to the half-arc 25, and I this angle is to be adjusted for each case separated by function of I speed and cross-section of the bar, alloy, temperature etc.

However, an aluminum film which is sufficiently thick to prevent the eutectic compounds from being pushed towards the surface is formed immediately and at the very beginning of the throat and on the side of the strip, by piercing this film during solidification. Because it is this push through the initial film which is responsible for the concentrations of eutectic compounds on the surface, on the side of the strip. In order to form this sufficiently thick film at the very beginning, the refrigeration system, on the side of the strip, is still provided with a 27 "orifice located at the very beginning of the throat, and the start of the jet of water leaving this orifice is adjusted so as to obtain a sufficiently thick film, without however unbalancing the cooling too much on the side of the strip relative to the other side.

i

The method according to the invention will preferably be used in a process for manufacturing aluminum wire rod Al-Mg-Si for electrical conductor, that is to say an alloy having as composition 0.3 to 0.9% of magnesium, 0.25 to 0.75 $ of silicon, 0 to 0.60 56 of iron, the rest of the metal being aluminum and impurities. With such an alloy, it is arranged that the continuous extrusion precedes a quenching down to a temperature below 260 ° C., during which the aluminum is rolled to obtain the wire rod, or we arrange this. that the continuous extrusion precedes a quenching step i 6.

purely thermal, that is to say without mechanical work, followed by a second thermomechanical step in which the aluminum is worked at a temperature ranging from 130 to 260 ° C. and is then subjected, before any subsequent work, to maturation.

In previous applications from the same inventor (LU 80.656 and 83.249) it has been explained that such treatment, where quenching can be preceded by hot work at a temperature as high as possible, preferably above 470 ° C ”and with minimal cooling in order to keep a maximum of alloying elements in supersaturated solution before quenching, gives a very advantageous metallographic structure. It is in this context that this hot work can be carried out by the extrusion step used in this invention. This is very advantageous, since it is a work * where the metal does not cool, on the other hand, heats up. And one obtains, in addition, the advantages of the present invention.

It should be noted that the metal used in the present invention may as well be pure aluminum or an aluminum alloy, that is to say where aluminum is the predominant component, the metal used being called under the term general of "aluminum".

It is clear that other variants or equivalents of the present invention may emerge from the present description, I without however departing from the scope of the present invention.

.7-

Claims (8)

1. A method for the continuous production of an elongated aluminum product, the method comprising a continuous casting of a casting bar followed by continuous rolling, characterized in that, between continuous casting and rolling, said casting bar is subjected to continuous extrusion. 2. Method according to claim 1, characterized in that the continuous extrusion is carried out by a friction extrusion. 3 · Process according to any one of Claims 1 and 2, characterized in that the extrusion orifice has the shape of a flat rectangle · i, 4 "Process according to any one of Claims 1 to 3" characterized by the fact that the continuous casting is carried out in a casting wheel whose rim comprises a groove covered by a flexible strip thus forming a pouring groove, the cooling on the side of the strip being delayed compared to the cooling on the side of the rim , except for a jet of water directed against said strip at the start of said pouring groove. 3. Method according to any one of claims 1 to 4>% characterized in that the aluminum is an Al-Mg-Si aluminum for electrical conductor. 6. Method according to claim 3 "characterized in that the continuous extrusion precedes quenching to a temperature below 260 ° C, during which the aluminum is rolled to obtain a wire rod. 7. Method according to claim 5 "characterized in that the continuous extrusion precedes a purely thermal quenching step, followed by a thermomechanical step in which the aluminide is worked at a temperature ranging from 130 to 260 ° C and is then subjected, before any subsequent work, to maturation. Λ '»8. 8. Installation for the use of the method according to any one of claims 1 to 7, comprising, arranged from upstream to downstream, a continuous casting installation of a casting bar and a continuous rolling mill, characterized in that the The installation comprises, between the continuous casting installation and the rolling mill, a continuous extrusion press. 9 · Installation according to claim 8, characterized in that the continuous extrusion press is a wheel for friction extrusion. i