MXPA01002825A - Aluminum die cast alloy having high manganese content - Google Patents

Abstract

Modified die-castable aluminum alloys resistant to mold soldering with low iron content and a higher manganese content by weight are disclosed. In each alloy the iron content is less than 0.6%by weight and the manganese content is about 1.0-2.0%by weight.

Description

ALUMINUM ALLOY FUSED AT PRESSURE THAT HAVE. HIGH MANGANESE CONTENT Field of the invention The present invention relates to aluminum-based alloys having substantially improved mechanical and pouring properties, and to a method for making products cast in metal molds from alloys. More particularly, the improved aluminum-based alloys comprise 1.0-2.0% by weight of manganese and a maximum of 0.6% by weight of iron.

Background and brief description of the invention The manufacturing industry, and more particularly the automotive industry, has been increasingly replacing ferrous materials with lighter materials such as aluminum. The demand for replacing lightweight materials has led to the development of aluminum alloys capable of forming structures that withstand stresses typically reserved for structures formed from ferrous metals. In addition to the increased strength (which includes both a high resistance to deformation REF. DO NOT. 127971 permanent as high values of elongation), an aluminum alloy should be able to empty into a metal mold, be resistant to corrosion, and be easily machined. Historically, the products obtained from the casting or casting of aluminum have been characterized by their relatively low ductility and strength when compared to forged products of similar compositions. This low ductility and strength are due to the presence of defects in the molten alloys, which are greatly eliminated by mechanical work in the forged alloys. These defects are mainly of two types: voids due to contraction or inclusions of gas, and somewhat large brittle particles due to the intermetallic phases formed of the impurity elements or oxide scale trapped in the casting or casting during solidification. The development of castings or higher quality casting processes results from changes in the composition of the alloy, and casting or casting techniques designed to minimize the number and importance of these defects. The highest quality cast aluminum alloys, for the most part, fall within the Aluminum / Silicon / Magnesium (Al-Si-Mg) type of alloy. The increased strength and ductility are achieved mainly by using a high purity inlet (low iron content and / or modification of AlSiFe5 by additions of Beryllium (Be)), and maintaining the cleanliness of the alloy. As a consequence of these changes, the properties of certain aluminum products, made by currently available emptying processes, can approach those forged products of equivalent composition. Recently aluminum alloys have been developed exhibiting these increased mechanical properties; such an improved aluminum alloy is described in U.S. Patent No. 5,573,606, issued November 12, 1996, to Evans et al., the disclosure of which is incorporated herein for reference purposes. The aluminum-based alloy described in the document by Evans et al. It has improved resistance to deformation and elongation values that are above the previously available aluminum alloys. In casting operations in metal molds, the alloys are emptied into molds that are commonly made of steel. Aluminum and steel form an intermetallic compound when brought into contact under appropriate conditions, at high temperatures for example. Therefore, the components cast in metallic molds from improved aluminum alloys, or from any aluminum alloy, can present a "welding with the metal mold" or a tendency on the part of the aluminum alloys to interact with the steel mold to form intermetallic compounds that stick or bind to the mold, delaying the step of removing the molten component from the mold. The iron is added to the aluminum alloys used in the casting operations, in order to reduce the welding of these (the alloys) with the metal mold. Iron concentrations that are above 0.7% by weight are those typically found in aluminum alloys, used in casting operations in metal molds. However, iron reduces the ductility of the alloy significantly and decreases the corrosion resistance of the alloy. Therefore, the manufacturing companies that are dedicated to melting in metal molds would welcome an aluminum alloy with a low iron content and that has improved mechanical and casting properties. The aluminum-based alloy of the present invention contains low concentrations of iron, higher concentrations of manganese and is less prone to welding with the metal mold. Although the effects of various elements on the mechanical properties of aluminum alloys have been studied, investigations have been conducted mainly based on relatively simple systems, binary or ternary alloys. Aluminum alloys, made from casting in more commercial metal molds, are complex alloy systems containing various alloys and impurity elements. The large number of elements found in these alloys, their low and varying concentrations and the possibility of interactions between the elements of the alloy, make the systematic study of the effect of the individual elements on the properties of commercial alloys very complicated. and hard. Without considering the difficulty of deciphering the effects that individual elements have on the mechanical properties of an alloy, elements such as iron, manganese, magnesium, copper, silicon, titanium and beryllium are accepted by professionals or specialists in the art because these elements have the following general effects on the properties of aluminum alloys: Iron is typically added to cast aluminum alloys by casting, in metal molds, for the purpose of preventing the aluminum alloy from sticking to a metal mold during the course of the casting operation, in metal molds ("welding with the metal mold ") and thus increase the ease of removing the aluminum alloy from the mold. However, the addition of iron decreases the elongation of the aluminum alloy. Manganese is added to aluminum alloys with the purpose of eliminating the adverse effect of the addition of iron. It has been believed that the percentage by weight of manganese, should rarely exceed half the percentage by weight of the iron in an aluminum alloy, this because an excess of manganese could result in a substantial decrease in the mechanical strength of the alloy of aluminum. Magnesium is typically incorporated to increase the tensile strength of the alloy; binary Al-Mg alloys have high strength, excellent resistance to corrosion, can be welded (weldability) and surface finish. However, while a high magnesium content increases the hardness and resistance to fatigue by the alloy, this high content also decreases the ductility of the alloy. One more reason to limit the magnesium content in the alloy is that magnesium can easily be oxidized to form magnesium oxide (MgO) particles, with measurements ranging in the range of the microns within the molten material. Keeping the spinel at elevated temperatures (above 750 ° C), which is a complex, octahedral, magnesium aluminum oxide crystal, which usually forms and grows rapidly forming scale in the molten product. These inlays reduce the properties of fluidity and elongation of the alloy. Copper can also be added to an aluminum alloy to increase the strength of the alloy. As the copper content increases, the hardness of the alloy also increases, but the strength and ductility depend on whether the Cu is in a solid solution, or as particles in the form of spheres and evenly or evenly distributed. Copper decreases the electrolytic potential as well as corrosion resistance. Copper-based alloys tend to be severely punctured in the annealed or heat-treated condition, and over time the hardness may be susceptible to stress corrosion or intergranular corrosion. Silicon is an important component of the alloy for purposes of improving the fluidity of the alloy in its molten state, during the course of the casting operation in metal molds. Al-Si alloys show low shrinkage and a reduced freezing range resulting in good resistance to tearing or hot breaking, density or strength as well as good weldability. Silicon in Al-Mg alloys reduces ductility and elongation without a compensatory increase in strength. The combined introduction of copper and silicon significantly increases the hardness of the alloy, but sharply reduces elongation. Titanium is widely used to refine the granular structure of cast aluminum alloys, often in combination with smaller amounts of boron. Titanium is often used in higher concentrations than those required for granular refining in order to reduce the fracture tendencies in hot charge or hot shot compositions.

Beryllium is added to alloys based on Al-Mg to prevent oxidation of the magnesium content of the aluminum alloy. Such a small amount ranging from 0.005% to 0.05% by weight of beryllium added to an alloy based on molten aluminum, causes the formation of a protective film of beryllium oxide on the surface. Without such protection offered by beryllium, there can be significant losses of magnesium during the casting process, due to the fact that magnesium is highly reactive with oxygen. Magnesium oxide by itself is incapable of forming a protective barrier in order to prevent the loss of magnesium. Beryllium is also an element that has been included in aluminum alloys in order to increase the resistance to corrosion, the strength and elongation of aluminum alloys. Therefore, according to the present state of the art, beryllium is routinely included in Al-Mg alloys: the percentages of beryllium vary with the magnesium content of the aluminum alloy. Contrary to the currently accepted teachings about the harm of adding manganese in concentrations higher than half the iron concentration, the applicant has discovered that the mechanical properties of a low iron content (below 0.7% by weight) in an alloy of Mg-Si-Al, are not substantially affected if the manganese content is increased so that it ranges between 1.0-2.0% by weight, while the susceptibility of the components cast in metallic molds is substantially reduced. from such alloy to be welded with the metal mold. The applicant's present invention is directed to a cast aluminum alloy, in metal molds, such alloy comprising 1.0-2.0% by weight of manganese, and a maximum of 0.6% by weight of iron. One embodiment of such an alloy also includes a maximum of 1.75% by weight of magnesium. A second embodiment of such an alloy with high strength includes 2.5-4.0% by weight of magnesium and a maximum of 0.003 by weight of beryllium. These aluminum alloys are useful for forming cast articles, in metal molds, of light weight, that is to say lightweight, which have superior elongation properties and do not present welding with the metal mold.

DETAILED DESCRIPTION OF THE INVENTION The aluminum alloys, which can be emptied (go) in metal molds, previously described, lack elongation properties and lack of susceptibility to be welded with the metal mold of the aluminum compounds present. The aluminum alloys with high content of manganese, and low iron content of the applicant, are not as susceptible to welding with the metal mold as the previous aluminum alloys with low iron content. The iron is added to the aluminum alloys to reduce the welding of these with the mold, and it is known that it effectively reduces the welding to the mold when it is present in an excess of 0.7% by weight. However, aluminum alloys containing iron in excess of 0.7% by weight, experience reduced ductility and corrosion resistance. Manganese is added to aluminum alloys to reduce the damaging effects of iron, combining with iron to form plate-like structures that resemble Chinese calligraphy. Manganese is usually controlled in an amount less than half the iron content by weight. In the aluminum alloys described, the iron content is limited to less than 0.6% by weight, and the manganese content is between 1.0-2.0% by weight. It is believed that the increased manganese content acts as a substitute for the reduced iron content to reduce the welding of the alloy with the metal mold. The strength of the present alloys can be increased by increasing their magnesium content coupled with a beryllium content of less than 0.003% by weight. The technique of incorporating small amounts of magnesium into the aluminum alloys in order to increase the strength of the alloy is known to those skilled in the art. By increasing the magnesium content beyond 2.5% by weight, the decrease in alloy elongation is reported. However, the aluminum alloys with high magnesium content of the applicant (2.5-4.0% by weight of magnesium) have an increased elongation on the aluminum alloys, which can be emptied into currently available metal molds. Beryllium has been described as an important component contained in aluminum alloys for its properties that prevent the oxidation of magnesium. It has also been thought that including beryllium increases the mechanical strength of the alloy. In fact, the applicant has discovered that decreasing the beryllium content in an aluminum alloy having a high magnesium content (2.5% to 4% by weight) will increase the elongation of the aluminum alloy. Accordingly, the beryllium-containing aluminum alloy of the present invention has been formulated to have a beryllium content of less than 0.003% by weight. More preferably, the beryllium content is less than 0.0003% by weight and more preferably the beryllium content is zero. The applicant's invention is directed to an aluminum alloy with 1.0-2.0% by weight of manganese, and a maximum of 0.6% by weight of iron. The alloys of the applicant include either less than 1.75% by weight of magnesium or 0.001-0.003% by weight of beryllium. The aluminum alloys according to the present invention also include elements selected from the group consisting of silicon, copper, zinc, nickel, titanium, chromium, tin and lead. The aluminum-based alloys that are emptied into metallic molds of the present invention also include certain impurities that can not have voids (including but not limited to calcium, cadmium, gallium and sodium). A preferred embodiment with high magnesium content according to the present invention comprises 1.0-2.0% by weight of manganese, a maximum of 0.6% by weight of iron, 2.5-4.0% by weight of magnesium, a maximum of 0.10% by weight zinc, a maximum of 0.45% by weight of silicon, a maximum of 0.10% by weight of copper and less than 0.003% by weight of beryllium, with the rest being aluminum. In a preferred embodiment of the present invention, aluminum alloy with high magnesium content comprises 2.5-4.0% by weight of magnesium, 1.0-2.0% by weight of manganese, 0.25-0.6% by weight of iron, 0.2-0.45% by weight of silicon, less than 0.003% by weight of beryllium, the rest being aluminum. In an alternative embodiment, aluminum alloy with a high magnesium content comprises 1.0-2.0% by weight of manganese, 2.5-3.0% by weight of magnesium, 0.05-0.10% by weight of copper, 0.25-0.6% by weight of iron , 0.2-0.45% by weight of silicon, less than 0.003% by weight of beryllium, the rest being aluminum. The Applicant has also found that by decreasing the iron content in common aluminum alloys, such as A356, A357 and A206, and increasing the manganese content to 1.0-2.0% by weight, there being a small effect or there is no such over tensile strength, resice to permanent deformation, or percentage of elongation while ductility and corrosion resice are increased and the susceptibility to welding with the mold increases. In a further alternative embodiment, the aluminum alloy comprises 1.0-2.0% by weight of manganese, 0.25-0.7% by weight of magnesium, a maximum of 0.20% by weight of copper, a maximum of 0.20% by weight of iron, 6.5 -7.5% by weight of silicon, a maximum of 0.20% by weight of titanium, and a maximum of 0.10% by weight of zinc, with the rest being aluminum. In yet another alternative embodiment, the aluminum alloy comprises 1.0-2.0% by weight of manganese, 0.15-0.350% by weight of magnesium, 4.2-5.0% by weight of copper, a maximum of 0.1% by weight of iron, a maximum 0.05% by weight of silicon, 0.15-0.2% by weight of titanium, and a maximum of 0.1% by weight of zinc, with the rest being aluminum. The aluminum alloy with a high magnesium content described by the Applicant has an increased strength compared to the aluminum alloys that can be cast in metal molds, currently available. In particular, the aluminum alloys with a high magnesium content described by the Applicant, provide a novel aluminum alloy that can be cast in metal molds, which has a permanent deformation resice greater than or equal to 16 ksi (110. MPa) and an elongation value greater than or equal to 17%. More preferably, the alloy has a resice to permanent deformation of 17 to 18 ksi (117-124 MPa) and an elongation value greater than or equal to 20%. The aluminum alloy of the present invention is prepared using dard procedures known to those of ordinary skill in the art. The present aluminum alloy can be used in dard casting processes, in metal molds, known to those skilled in the art to form a variety of lightweight articles, cast in metal molds. Preferably a vacuum evacuation process is used, wherein the process includes extracting a vacuum from the molding cavity and the passages (the channel system for the molten metal including the loading sleeve or sleeve and the transfer tube towards the furnace) through which the molten metal is fed to remove air that might otherwise be trapped by the molten metal. The process of using this vacuum system to extract the molten metal from the load sleeve is assigned or referred to as operating or handling the vacuum-ladle. A preferred process for pouring the present aluminum alloy into metallic molds uses VERTICAST type dump machines. VERTICAST type machines are machines for emptying in metal molds, known in the trade or specialty for their vertical orientation, particularly an orientation in which the upper and lower molds are supported, respectively, on upper and lower plates to provide a plurality of molding cavities, spaced around a vertical central axis with a loading sleeve or sleeve, and an injection piston arranged vertically to force the molten metal up into the cavities of molding arranged concentrically. However, the aluminum alloy of the present invention can also be melted with equal efficiency in horizontal, vacuum machines that have been modified to operate or handle the evacuation evacuation spoon of the metal mold under vacuum. More preferably, the empty aluminum alloy, using the process described in U.S. Patent No. 5,211,216, the disclosure of which is incorporated herein for reference purposes. This process ensures a minimum contact of the alloy with the oxygen in the atmosphere, thus reducing the need for beryllium in the Al-Mg alloy to control the oxidation of magnesium. The present aluminum alloy can be used to form a variety of automotive parts not limited to steering wheels, steering columns, instrument panels and instrument panel members, seat backs and bottom seats, wraps or cans / air bag modules, wheel hoops, and energy absorbing brackets. The alloy is particularly suitable for any application that presents impact and loading requirements, where high elongation properties are desirable.

Example 1 Comparison of the strength of Al-Mg alloy with and without increased Mn The mechanical properties tests were carried out using an MTS type tester or tester; The testing procedure followed the ASTM (American Society for Testing and Materials) standard B 557-84, entitled "Standard Methods of Testing Wrought and Cast Aluminum-and Magnesium-Alloy Products". The tensile strength, resistance to permanent deformation and elongation were measured using a bar for emptying tests in metal molds (see figure 1). The test bar has a minimum length of at least 228.6 mm (9 inches), a reduced section A of 57.15 mm (2.25 inches) minimum, a length G of thickness or gauge (50.8 mm (2.00 inches) in length, a diameter D of 6.35 mm (0.250 inches) in length, and the flat end portions F for hardness tests (38.1 mm (1.5 inches) in length) The distance between the handles or handles B is a minimum of 114.3 mm (4.5 inches) ) and the diameter of the two C-end sections is 9,525 mm (0.375 in.) A chart recorder was used to record and display load displacement diagrams, and the load versus displacement data was stored on a computer for The stress resistance (RT) was calculated by dividing the maximum load between the original cross-sectional area of the reduced section of the specimen.The load value at the fracture is the maximum load for the specimen. try Thus, this maximum value is automatically stored in your computer's operating system and then deployed. The maximum load can also be calculated from the curve of the load versus the displacement displayed on the chart or stored in the computer that makes the records. The maximum load stored in the operating system of the computer of the machine was used in the calculation of the resistance to the voltage RT. The specimens emptied in used metal molds were not perfectly round; the dimensions of the cross-sectional area varied slightly from specimen to specimen. The maximum and minimum diameters in the center of the reduced section were measured for each specimen, and the average of the maximum and minimum diameters was used as the diameter to determine the original cross-sectional area of the specimen. Elongation is the increase in the length of the length of the gauge or thickness, expressed as a percentage of the length of the original gauge. The original gauge length of 50.8 mm (2.0 inches) and measured carefully and marked. The increase in the length of the caliber length was carefully determined by placing together the ends of the fractured specimen and measuring the distance between the caliper marks. The elongation can also be calculated based on the curve of the load versus the displacement. In this method, the increase in length (plastic extension) is estimated by subtracting the elastic extension of the total extension in the fracture. This requires that the curve show a clear initial straight line, which represents the elastic deformation of the specimen. The resistance to permanent deformation was determined by the "displacement method" at a displacement of 0.2%. In this method a straight line is drawn on the stress-strain diagram, parallel to the initial straight line in the stress versus strain curve. This line is placed at a distance of 0.2% of the length of the reduced section from the initial straight line in the direction of the deformation axis. The stress at this point, where the straight line drawn and the stress-strain curve intersect, is the resistance to permanent deformation. In these experiments the load versus displacement curve showed two straight lines at the beginning of the load, and the first line was shorter than the second. In these experiments, the resistance to permanent deformation was calculated based on the second line, which showed a reasonable concordance with the specification bars and a relatively small variation. To determine the effect of the increased manganese content on the aluminum alloy with high magnesium content described in Evans et al. (Alloy # 2), in the resistance to maximum permanent deformation (Ultimate Tensile Strenght), resistance to deformation (Yield Strenght) and elongation of the aluminum alloys, aluminum alloys with a high content of manganese were tested having compositions with the following percentage weights, producing the following results: Alloy # 2 Alloy Modified New Alloy Mg 2. 83 2.75 2.80 Fe 0. 25 0.30 0.30 Yes 0. 20 0.20 0.20 Mn 0. 60 0.70 1.00-2.00 Cu 0.07 0.05 0.05 Be 0.003 0.003 0.003 UTS (ksi) 32.5 (224 MPa) 32.7 (225 Mpa) 33.0 (227 MPa) YS (ksi) 17.0 (117 MPa) 18.0 (124 MPa) 18.0 (134 MPa) Elong (%) 22.5 20.5 20.6 Welding Occasional Low None The data indicate that the presence at most of 1.0% by weight of manganese increases the resistance to maximum permanent deformation UTS and the resistance to permanent deformation YS, while reducing the elongation to less than 10% and eliminating the welding of the alloy with the metal mold.

Additional Al-Mg compositions were tested to determine if increased levels of manganese by weight could reduce weld with the metal mold, even when iron concentrations were reduced by weight. For example it was found that the alloy A356 with a maximum of 0.60% by weight of iron content, and with a maximum content of 0.20% by weight of manganese content was emptied could be presented the welding of such alloy with the metal mold . However, when the manganese content in alloy A356 was increased above 1.0% by weight, no welding of such alloy with the metal mold was observed.

It is noted that in relation to this date, the best method to carry out the aforementioned invention, is that which is clear from the manufacture of the objects to which it refers.

Claims (32)

CLAIMS Having described the invention as above, the content of the following claims is claimed as property:

1. An alloy based on aluminum, said alloy is characterized in that it comprises: 1.0-2.0% by weight of manganese; a maximum of 0.6% by weight of iron; less than 0.003% by weight of beryllium; being of the rest aluminum; and said alloy is also characterized in that when it is used in casting operations, in metallic molds, the welding of this (the alloy) with the metallic mold is reduced.

2. The aluminum alloy of claim 1, characterized in that it further comprises 2.5-4.0% by weight of magnesium and 0.001-0.003% by weight of beryllium, and because said alloy has an elongation value of at least 17%.

3. The aluminum alloy of claim 2, characterized in that it comprises a maximum of 0.45% by weight of silicon.

4. The aluminum alloy of claim 3, characterized in that it comprises a maximum of 0.10% by weight of copper.

5. The aluminum alloy of claim 1, characterized in that it comprises a maximum of 0.45% by weight of silicon, and because it has an elongation value of at least 17%.

6. The aluminum alloy of claim 5, characterized in that it comprises 2.5-4.0% by weight of magnesium.

7. The aluminum alloy of claim 1, characterized in that it comprises less than 1.75% by weight of magnesium.

8. The aluminum alloy of claim 7, characterized in that it comprises a maximum of 0.10% by weight of zinc.

9. The aluminum alloy of claim 7, characterized in that it comprises a maximum of 0.2% by weight of titanium.

10. The aluminum alloy of claim 8, characterized in that it further comprises 4.2-5.0% by weight of copper.

11. The aluminum alloy of claim 8, characterized in that it also comprises a maximum of 0.2% by weight of copper.

12. An aluminum-based alloy for use in the formation of a cast (molten) product in a metal mold, said alloy is characterized in that it has an elongation value of at least 17%, said alloy comprises: 2.5-4.0% by weight of magnesium; 1.0-2.0% by weight of manganese; 0.25-0.6% by weight of iron; 0.2-0.45% by weight of silicon; less than 0.003% by weight of beryllium; being of the rest aluminum.

13. The aluminum alloy of the claim 12, characterized in that it also comprises 0.05-0.10% by weight of copper.

14. The aluminum alloy of the claim 13, characterized in that it also comprises a maximum of 0.10% by weight of zinc.

15. An aluminum alloy that can be cast in modified metal molds, which in its unmodified form includes iron in a certain percentage by weight, to at least reduce it to be welded with the metal mold, and manganese in a lower percentage by weight than iron, characterized because it comprises: a maximum of 0.6% by weight of iron; and manganese in a percentage by weight higher than the percentage by weight of iron.

16. The aluminum alloy of claim 15, characterized in that the manganese is present at 1.0-2.0% by weight.

17. The aluminum alloy of claim 15, characterized in that the manganese is present in a percentage by weight higher than the certain percentage by weight of the iron in the unmodified form of the alloy.

18. The aluminum alloy of claim 15, characterized in that the manganese is present at approximately 1.0% by weight.

19. A structural article of manufacture, characterized in that it comprises an aluminum alloy having a permanent deformation resistance greater than or equal to 11.95 kgf / m2, and an elongation value greater than or equal to 18%, said aluminum alloy comprises 2. 5-4.0% by weight of magnesium; 1.0-2.0% by weight of manganese; a maximum of 0.6% by weight of iron; a maximum of 0.45% by weight of silicon; a maximum of 0.10% by weight of copper; less than 0.003% by weight of beryllium; being of the rest aluminum.

20. The article of claim 16, characterized in that the aluminum alloy comprises about 1.1% manganese by weight.

21. An aluminum alloy that can be emptied into metallic molds, characterized in that it comprises: 0.25-0.70 by weight of magnesium; 1.0-2.0 by weight of manganese; a maximum of 0.2% by weight of iron; 6.5-7.5% by weight of silicon; a maximum of 0.2% by weight of each of the additional elements selected from the group of zinc, copper, titanium and beryllium; the rest being aluminum; and said alloy is further characterized because when it is used in casting operations, in metallic molds, the welding of this (the alloy) with the metallic mold is reduced.

22. The alloy of claim 21, characterized in that as an additional element, zinc is present at a maximum of 0.1% by weight.

23. The alloy of claim 22, characterized in that as an additional element, copper is present at a maximum of 0.2% by weight.

24. The alloy of claim 23, characterized in that as an additional element, titanium is present at a maximum of 0.2% by weight.

25. The alloy of claim 24, characterized in that the magnesium is present at 0.25- 0.45% by weight.

26. The alloy of claim 24, characterized in that as an additional element, beryllium is present at 0.04-0.07% by weight.

27. The alloy of claim 25, characterized in that the magnesium is present at 0.4-0.7% by weight.

28. An aluminum alloy that can be emptied into metal molds, characterized in that it comprises: 0.15-0.35% by weight of magnesium 1.0-2.0% by weight of manganese; a maximum of 0.1% by weight of iron; 4.2-5.0% by weight of copper; a maximum of 0.2% by weight of each of the additional elements selected from the group of zinc, silicon, nickel, tin and titanium; being of the rest aluminum; and said alloy is characterized because in addition when it is used in casting operations, in metal molds, the welding of this (the alloy) with the metal mold is reduced.

29. The alloy of claim 28, characterized in that as an additional element, zinc is present at a maximum of 0.1% by weight.

30. The alloy of claim 29, characterized in that as an additional element, silicon is present at a maximum of 0.05% by weight.

31. The alloy of claim 30, characterized in that as an additional element, titanium is present at a maximum of 0.2% by weight.

32. A method for producing components by casting in metal molds, an aluminum alloy with reduced tendency to be welded with the metal mold, the method is characterized in that it comprises the steps of: providing an aluminum alloy having magnesium, zinc, silicon, copper, beryllium , titanium, nickel, and tin present in percentages by weight consistent with a known aluminum alloy; maintain the iron content of the alloy provided, at the level of the iron content of the known aluminum alloy or below this level; adjust the manganese content of the alloy so that it is between 1.0-2.0% by weight; heat the alloy to a suitable temperature to empty in metal molds; emptying a component from the alloy; and removing the cast component from the metal mold.