DE19915238A1 - Magnesium alloy used e.g. in the manufacture of gear housing contains traces of cadmium, iron, nickel and lithium - Google Patents

Abstract

Magnesium alloy contains traces of less than 1.8 (wt.%) cadmium, 0.1 Cu, up to 0.05 Fe, up to 0.005 Ni and 0.5-20 Li. The alloy has a tensile strength of at least 227 MPa, an energy absorbed in fracturing of at least 72 J and a breaking elongation of at least 26%. An Independent claim is also included for a process for the production of a semi-finished product comprising melting the alloy at 550-900o C, forming a molded body by casting with or without pressure, and the heat treating.

Description

The invention relates to magnesium alloys of high ductility, processes for their Production and their use, in particular lithium-containing magnesium alloys.

Because of their very low density, magnesium alloys are approximately in the range from 1.2 to 1.9 g / cm ³ , occasionally, especially in the case of particularly lithium-rich magnesium alloys, down to about 0.9 g / cm ³ as metallic construction materials of particular interest for vehicle and aircraft construction. In the future, they will be used more and more for the lightweight construction of motor vehicles and airplanes in order to be able to compensate for the weight of additional elements due to increasing comfort and safety standards, particularly in new low-emission automobiles. They are also of interest for transportable devices or systems that are particularly light-weight for other reasons. The lightweight construction enables the construction of energy-saving vehicles and planes such as. B. the 3-liter motor vehicle. Among the manufacturing processes, die casting and shaping, extrusion, forging, rolling and possibly subsequent forming such as stretching or deep drawing will become increasingly important in the future, since lightweight construction components such as B. seat, window and door frames, elements of vehicle cells and outer skins, housings, floor elements, covers, tank elements, tank flaps, brackets, supports, brackets, angles, crash elements, impact absorbers, impact shields and impact carriers, small parts or corresponding components for aircraft, for which there is an increasing demand.

The cold formability of the commercially available magnesium alloys is due to the hexagonal crystal structure and the associated low ductility limited. Polycrystalline magnesium and most magnesium alloys behave becomes brittle at room temperature. For a number of applications or for certain Manufacturing process of semi-finished products from magnesium alloys is in addition to good ones mechanical properties such as high tensile strength require ductile behavior. On improved forming, energy absorption and deformation behavior requires a higher one Ductility and possibly higher strength and toughness. For this are  To develop magnesium alloys with these properties or their To further develop manufacturing processes because many material variants match the manufacturing condition have widely varying material properties.

Ductility is the ability of a material to undergo a permanent change in shape, which in the uniaxial state is ideally without any elastic component according to the stress-strain diagram. This property is limited by the occurrence of the break. In general, the permanent elongation achieved in the tensile test up to fracture is considered ductility. As a measure of the ductility, the constriction of the fracture, impact work and notch impact work can also be viewed, each with a slightly different statement. These properties can be determined in accordance with EN 10 002, Part 1, or in accordance with DIN 50115 and 50116. The elongation at break A = A _plast characterizes the change in shape with its plastic part under a largely uniaxial load; in addition, according to the stress-strain diagram, the elastic part of the strain A _elast and the sum of the elastic and plastic part D = ΣA = A _elast + A _plast can be determined. A highly plastic material is called ductile.

When specifying the elongation at break and the tensile strength to different Magnesium alloys make it clear that the elongation at break is often all the higher can take if only medium high tensile strength values are reached and that conversely, only medium-high values of elongation at break with high values of tensile strength be achieved. Very high values of tensile strength can only be achieved by comparison reach low elongation at break values.

The elasticity denotes the elastic part of the stress-strain diagram according to Hook's law, where with ideal linear-elastic relationships no permanent change in shape occurs.

Furthermore, the yield point ratio V can be specified as the ratio of the yield stress F = R _P02 to the tensile stress Z = R _m . This results in two values for the largely uniaxial load that characterize the elasticity, two the plasticity and two their relationship to one another. The ratio of the elastic to the plastic part of the stretch gives the best approximation to reality.

The impact work is above all a measure of the energy consumption of a semi-finished product and for plastic behavior, i.e. for deformability and rate of deformation. A high impact work is therefore essential for the use of deformation elements such. B. Crash elements, impact absorbers, impact shields and impact carriers. The impact work - measured on notched samples - is u. a. due to higher absolute values for Magnesium alloys more meaningful than the impact energy and affects one largely uniaxial load. The impact work, which is always on notched samples is determined also indicates the susceptibility of a material to triaxial failure Burden. Their informative value is particularly low if the execution of the Notch significantly affects the values of the impact energy. The blow job and the Impact energy is measured under dynamic load and can be an indication give up on energy absorption and deformability. Tensile and compression tests are carried out in the Comparison under quasi-static loads. A conclusion from uniaxial on Multi-axis properties or relationships are only partially possible.

The values listed below measured on samples in a particular The state of manufacture therefore reflects the current material properties. she provide an indication of the forming behavior that previously occurred during the forming process was. In this state it is a conclusion about the properties and behavior of a person Semi-finished product or even a component with this semi-finished product, which may be further refined later use possible. Furthermore, there is a conclusion about the material properties formed alloys possible, the z. B. by bending, pressing, pressure rolling, Stretch drawing, deep drawing, hydroforming or roll forming processed semi-finished products are to be shaped. Because the change in Material properties from cast to extruded condition similar to that Change in material properties from cast to forged, rolled or a similar reshaped state is therefore also an inference to one other forming condition possible.

For the use of lightweight components, the elastic is usually used Properties (stiffness) lifted, as far as it is not such. B. in an accident on the Deformation properties and thus on the energy absorption of the element and on the plastic behavior arrives. Therefore, regarding the u. U. multiple forming especially the plastic ones and for the use the plastic ones and / or elastic ones Properties matter. These properties are typically for use on the  respective ambient temperature, in extreme cases in the range from -40 ° C to + 90 ° C individual points in the vehicle or plane, however, to the locally lower or higher Turn off temperatures. However, the load state is usually multi-axis. The Conclusion from uniaxial to multiaxial loading conditions is all the more possible, ever more of an isotropic structure.

For the manufacture of such automotive elements, the manufacture is particularly suitable by die casting or extrusion, forging and / or rolling, prerequisite for the use of semi-finished products made of magnesium alloys or from them or with them Components manufactured in automobiles can meet certain property profiles depending be after application such. B. for deformation elements, seat and door frames Tensile strength of the light material of at least 100 MPa, preferably at least 130 MPa, together with an elongation at break measured at room temperature of at least 10%, preferably at least 15%. The higher the tensile strength, Elongation at break and other properties due to high ductility and energy absorption point out, the more suitable these semi-finished products or components are generally for the Commitment. Furthermore, higher strength values and higher ductility are also one Relief and partly also a prerequisite for the forming of cast blanks or for the further forming of already formed blanks or semi-finished products. The higher these properties are as cast, the higher these are usually even in the deformed state. A higher ductility can the forming or the renewed Forming, especially extrusion, easier. Therefore an elongation at break of at least 10% also for the subsequent manufacturing steps to form elements Magnesium alloys helpful. Therefore, tensile strength of at least 150 MPa measured at room temperature, preferably at least 180 MPa, or an elongation at break of at least 18%, preferably of at least 20%, particularly preferred of at least 25%, recommended. Usually this is Elongation at break in the commercially available magnesium alloys measured at Room temperature less than 12%.

With stronger substitution of other alloys by magnesium alloys to by Weight savings to save fuel or the installation of additional elements without Allowing weight gain is the advancement of the technology of the well-known Magnesium alloys and research into other magnesium alloys necessary especially with regard to the combination of properties ductility - strength.  

Basically, there are various options for increasing the ductility and thus the elongation at break in magnesium alloys and related lightweight materials:

• 1. A very limited possibility of this increase results from the optimization of the Manufacturing process in connection with heat treatment processes and / or over optimized manufacturing parameters e.g. B. in extrusion. However, it is important when forming e.g. B. by extrusion that the dynamic recrystallization occurring is not Coarse grain formation leads. Because the energy consumption and the mechanical properties of an alloy should generally be larger the smaller the average grain size is. The goal of alloy development can be a modification of the structure by forming temperature-stable precipitates and / or stabilization the structure by influencing the grain growth to be as fine a grain as possible and to produce the lowest possible porosity.
• 2. When the crystal structure of the Mg main phase changes from the hexagonally closest Ball packing on the cubic body-centered crystal structure z. B. due to a higher Adding a doping element such. B. at least 10.8 wt .-% Li, without further doping elements a homogeneous β-lithium-magnesium mixed crystal produce an improved elongation at break and better formability Room temperature due to an increased number of sliding systems. Indeed strength and corrosion resistance may deteriorate.
• 3. Since grain boundaries and other structural inhomogeneities or structural defects such. B. Inclusions, pores, coarse deposits, oxide streaks and segregations in the Movement of dislocations can act as barriers, a refinement of the structure, a reduction in structural inhomogeneities / defects or an avoidance certain structural inhomogeneities / defects to increase the strength, the Elongation at break and energy consumption. The connections are however in Very complex in individual cases. Grain refinement is an important tool for more To activate deformation systems that slide grain boundaries and new flow processes allow at room temperature and thus improve ductility. This can be done through the Adding grain-fine additives or / and through heterogeneous nucleation during solidification of cast materials made of alloys with certain additives.

Even the commercially available Mg casting alloys or wrought magnesium alloys are in the cast and, if necessary, subsequently formed, in particular extruded, pressed, rolled or / and forged and if necessary thereafter heat-treated condition  Usually previously relatively low ductility and low Energy absorption. For the inexpensive manufacture of semi-finished products, in particular for vehicles and airplanes, there is a need for suitable alloys and simple ones Process for the production of magnesium alloys with somewhat increased strength and greatly increased ductility.

Since the interest in wrought magnesium alloys has only increased somewhat in recent years So far, only a limited number of alloys are available for large-scale use to disposal. These are alloys based on Mg-Al-Zn such as B. AZ31, AZ61 and AZ80, based on Mg-Zn-Zr such as B. ZK40 and ZK60 or based on Mg-Mn such. B. M1.

Haferkamp, Bach, Bohling & Juchmann (Proc. 3 ^rd Int. Magnesium Conf. Manchester April 10-12, 1996, The Institute of Materials, London 1997, ed .: GW Lorimer) or Haferkamp, Bach & Juchmann ("Stand und Trends in the development of density-reduced magnesium materials ", lecture at the advanced training event" Magnesium Properties, Applications, Potentials "of the German Society for Material Science Clausthal-ZeNerfeld 1997) describe lithium-containing magnesium alloys based on MgLi without and with Al, AlZn, Ca, Si, SiCa , AlCa, CaAlZn or SiAlZn. For the elongation at break or tensile strength, values for MgLi40at% Al6at% z. B. of 19% or about 260 MPa, for MgLi40at% Si3at% 29% or about 152 MPa and for MgLi40at% 42% or about 134 MPa. Due to the small laboratory extrusion press used for those experiments, however, the forming speed and the degree of forming were low.

Furthermore, Haferkamp, Bach, Bohling & Juchmann at the Magnesium Conference in Garmisch-Partenkirchen 1992 (Magnesium Alloys and Their Applications, Eds .: B. L. Mordike & F. Hehmann, Oberursel 1992, 243-250) values of elongation at break and Tensile strength carried forward, that of MgLiAl, possibly with Zn, up to 25% and 239 MPa led.

NASA report N67-22072, SP-5068, Properties and current applications of magnesium lithium alloys, 1967, indicates possibilities for increasing the strength of those containing lithium Magnesium alloys and reports on singular values of high elongation at break or high tensile strength, but it can be assumed that the usual at that time Manufacturing process and available raw materials high  Impurities occurred that greatly influenced the result in this regard and Corrosion resistance compared to today's high-purity alloys significantly impaired.

It was therefore the task of magnesium alloys with increased ductility and, if possible also increased energy consumption, strength and toughness by choosing the one for this Propose the most likely to be effective parameters that are as low as possible Have density and also made as simple and inexpensive as possible can be.

The problem is solved with a magnesium alloy, the additives or traces of Cd less than 1.8% by weight and the traces of up to 0.1% by weight of Cu, up to 0.05% by weight of Fe and may contain up to 0.005% by weight of Ni, the Li content of 0.5 to 20% by weight of which Tensile strength at least 227 MPa, the impact energy measured on notched specimens at least 72 J and their elongation at break measured on tensile specimens at least 26% is.

The remaining contents of the chemical composition mentioned exist predominantly or essentially of magnesium. Levels of cadmium interfere with the Processing only because of their toxicity, but are otherwise particularly with regard to Formability is an advantage. Traces of copper, iron and nickel should be as possible be low since they affect the processing and / or the material properties impact.

The composition of the magnesium alloys varied only slightly or almost at all not from the composition of the melt to the composition before or after Extrusion to the composition of the semi-finished product made from it.

The task is solved with the same chemical compositions with a Magnesium alloy, the content of Li 0.5 to 20 wt .-%, the tensile strength at least 250 MPa, the impact energy measured on notched specimens of at least 72 J and their Elongation at break measured on tensile specimens at least 21%, preferably at least 30% is or  whose Li content is 0.5 to 20% by weight, whose tensile strength is at least 276 MPa, whose Impact work measured at least 70 J on notched specimens and their elongation at break measured on tensile samples is at least 18%, preferably at least 25%.

The problem is also solved with a magnesium alloy, the additives or traces of Cd less than 1.8% by weight and the traces of up to 0.1% by weight of Cu, up to 0.05% by weight Fe and up to 0.005 wt .-% Ni can contain, in addition to Mg 0.5 to 10 wt .-% Al and 0.1 contains up to 3% by weight Mn, the tensile strength of which is at least 200 MPa, the elongation at break measured on tensile specimens at least 12%, the compressive strength of which is at least 240 MPa and the impact energy of which, measured on notched specimens, is at least 25 J.

The task is also accomplished with a magnesium alloy that has additives or traces Cd less than 1.8% by weight and traces of up to 0.1% by weight of Cu, up to 0.05% by weight Fe and up to 0.005 wt .-% Ni can contain, in addition to Mg 0.5 to 10 wt .-% Al, 0.1 to Contains 3 wt .-% Mn and 0.5 to 20 wt .-% Li and their elongation at break measured on Tensile tests is at least 12%.

The task is also accomplished with a magnesium alloy that has additives or traces Cd less than 1.8% by weight and traces of up to 0.1% by weight of Cu, up to 0.05% by weight Fe and up to 0.005 wt .-% Ni can contain, in addition to Mg 0.5 to 10 wt .-% Al, 0.1 to 3% by weight of Zn and 0.5 to 20% by weight of Li, the tensile strength of which is at least 210 MPa, their elongation at break measured on tensile specimens at least 20% and their impact energy measured at least 90 J on unslotted samples. Your compressive strength can at least 350 MPa, preferably at least 365 MPa, particularly preferably at least 380 MPa. The magnesium alloy preferably has a content at least one rare earth element SE including Y of at least 0.1% by weight each SE on, particularly preferably of at least 0.5 wt .-%, very particularly preferably of at least 0.6 wt .-%, and / or a content of at least one element from the Group of cerium, praseodymium, neodymium, samarium, gadolinium, ytterbium, lanthanum and Yttrium. In any case, the total content of all rare earth elements is up to 1% by weight.

The task is also accomplished with a magnesium alloy that has additives or traces Cd less than 1.8% by weight and traces of up to 0.1% by weight of Cu, up to 0.05% by weight Fe and up to 0.005 wt .-% Ni can contain, in addition to Mg 0.1 to 3 wt .-% Zn and each contains 0.1 to 1 wt .-% of at least one rare earth element and / or Y, the  Tensile strength at least 230 MPa, the impact energy measured on notched specimens at least 50 J and their elongation at break measured on tensile specimens at least 20% is. It preferably has a yield strength, measured on tensile specimens, of at least 170 MPa.

The task is also accomplished with a magnesium alloy that has additives or traces Cd less than 1.8% by weight and traces of up to 0.1% by weight of Cu, up to 0.05% by weight Fe and up to 0.005 wt .-% Ni can contain, in addition to Mg 0.1 to 3 wt .-% Zn each 0.1 to 1% by weight of at least one rare earth element including Y and 0.5 to 20 Wt .-% Li and their elongation at break measured on tensile specimens at least 20% is.

The problem is also solved with a magnesium alloy, which essentially consists of a Alloy is selected from the group of alloys based on AM, A2 or ZE and the addition of lithium, manganese, aluminum, calcium, strontium, zinc, Zirconium or at least one rare earth element including yttrium may contain. Here, the term "essentially" means that the contents of others are not specific mentioned elements of up to 8 wt .-% can occur, preferably up to 4 % By weight.

The object is also achieved by means of at least one addition from the group of Lithium, calcium, strontium, zirconium and at least one rare earth element SE including yttrium modified magnesium alloy, the additions or traces of Cd less than 1.8% by weight and the traces of up to 0.1% by weight of Cu, up to 0.05% by weight of Fe and may contain up to 0.005% by weight of Ni, the compressive strength of which is at least 260 MPa has, preferably at least 300 MPa, particularly preferably at least 340 MPa, very particularly preferably at least 380 MPa, the impact energy measured on notched samples at least 72 J, preferably at least 90 J, and their Elongation at break measured on tensile specimens is at least 18%, preferably at least 20%, particularly preferably at least 22%, very particularly preferred at least 24%. Their tensile strength can be at least 260 MPa, preferably at least 290 MPa, particularly preferably at least 320 MPa. Preferably, these have Magnesium alloys based on AM, AZ or ZE.  

The semifinished product or component according to the invention preferably consists essentially of a magnesium alloy selected from the group of alloys based AM, AS, AZ, EZ, MA, SA, ZA or ZE with added lithium. The total salary In any case, rare earth elements is only up to 1% by weight.

The magnesium alloy can determine a plastic portion of the stress in Tensile tests according to the stress-strain diagram from the difference of Have tensile stress and yield stress of at least 50 MPa. The above Material properties according to the invention apply in particular to formed Magnesium alloys. It can have a structure with an average grain size of at most Have 50 microns, preferably at most 25 microns, particularly preferably at most 15 µm, very particularly preferably not more than 8 µm. The structure can help Grinding can be determined with the usual stereometric methods. she can extruded, rolled or / and forged and a dynamically recrystallized fine-grained structure, especially with an average grain size of not more than 20 µm, and have an elimination phase content of not more than 5% by volume, preferably not more than 3.5 or even not more than 2% by volume.

The object is also achieved with a method for producing a semi-finished product a magnesium alloy according to the invention or one produced therewith or from it Component or / and composite with at least one such semi-finished product or component that characterized in that the alloy at temperatures in the range of 550 to 900 ° C melted and one or more moldings by casting with or without additional pressure is produced and, if necessary, also heat-treated afterwards. Sand casting, gravity die casting, continuous casting, squeeze casting or die casting are preferred worked.

Usually, there are higher material properties when the cast one Shaped body, if necessary, then heat-treated if necessary, then reshaped, in particular by extrusion, forging and / or rolling, and after that, if necessary is heat treated. The molded body to be formed is preferably - in particular a Block, a bolt or a slab - at temperatures in the range of 300 to 420 ° C above Homogenized for 0.5 to 48 h, particularly preferably in the range from 330 to 380 ° C. over 2 to 24 hours. In particular, the molded body to be reshaped at extrusion temperatures Range of 100 to 450 ° C, preferably in the range of 180 to 320 ° C, extruded  become. Here, with a pressing speed in the range of 0.5 to 20 m / min are extruded, preferably at 1 to 18 m / min, particularly preferably at 5 to 16 m / min, very particularly preferably at 10 to 15 m / min. In addition, the molded body, the Semi-finished product or component after forming at temperatures in the range of 50 to 200 ° C be outsourced, preferably in the range of 80 to 150 ° C. The reshaped Shaped body or the shaped semi-finished product can be deformed further, for. B. by Stretch drawing, deep drawing, bending, pressing, pressure rolling, hydroforming, Roll profiling, and / or be straightened. The molded body, the semi-finished product or component can be processed after the original shaping, shaping or after further shaping, e.g. B. by turning, milling, drilling, separating, tumbling, punching, deburring, shaping, Grinding, lapping or / and polishing. B. by degreasing or de-oiling or / and are surface treated e.g. B. by pickling and / or coating, especially by painting. Furthermore, the molded body, the semifinished product or / and Component by at least one low-heat joining process such. B. gluing, riveting, plugging, Pressing, pressing in, clinching, folding, shrinking or screwing or / and at least one heat-generating joining process such. B. composite casting, Composite forging, composite extrusion, composite rolling, soldering or welding, in particular beam welding or fusion welding, with at least one of the same type or other types of molded body, semi-finished product or component. The different types of elements can be made, for example, from a magnesium-poor or -free Alloy exist, e.g. B. from an aluminum alloy or a steel.

The object is further achieved with a semi-finished product from an inventive one Magnesium alloy or with a component or composite made therewith or from it with at least one such semifinished product or component or can according to method according to the invention be produced.

It has been shown that the modification of grain sizes and phase distributions the alloying of accompanying elements such as lithium or rare earth elements SE including yttrium and lanthanum as well as their mixtures is helpful in producing significantly stronger and / or more ductile magnesium alloys. Above all an addition of Lithium or at least one rare earth element such. B. cerium, praseodymium, neodymium, Samarium, Gadolinium, Ytterbium, Lanthanum and Yttrium has proven to be cheap Further development of magnesium alloys proven.  

For the purposes of this application, semi-finished products are understood to be shaped articles which have not yet are finished and ready for use for their respective application. As components on the other hand, the molded articles are suitable for the intended purpose designated. However, both terms flow smoothly into one another, since it is the same shaped body for one purpose around a semi-finished product, but for the other can already be a component. Furthermore, for the sake of linguistic Simplification does not strictly differentiate between semi-finished products and components throughout the text or both mentioned at the same time or only spoken of magnesium alloy, although both can be meant.

The semifinished products made from magnesium alloys according to the invention or from them or with them manufactured components can be used as gearboxes, steering wheel skeletons, Wishbones, frame elements, elements of vehicle cells or vehicle outer skins, Cockpit support, housing, floor elements, covers, tank elements, tank flaps, Brackets, supports, beams, angles, hollow profiles, pipes, deformation elements, Crash elements, crash absorbers, impact absorbers, impact shields, impact carriers, small parts such as Gears, as impellers and other types of wheels, as welded profile constructions, for the vehicle body, for seat, window or / and door frames, as semi-finished products or Component in the automobile or airplane.

Process for the production of extruded profiles

The process for the production of extruded profiles from the inventive Alloys are filed on the same day by the same applicant Patent application described in detail; that application is considered by its name as in fully included in this application.

It is preferable to start from high-purity, commercially available alloys. Possibly. these alloys are alloyed with additives. The high-purity alloys can absorb small amounts of contaminants from the crucible during the melting process. The alloys can, for example, in a nickel and chrome-free steel crucible under a protective gas atmosphere, for. B. Ar or / and SF ₆ , are melted. The process steps are known in principle, but require a different modification or optimization depending on the alloy.

A prerequisite for the further processing of magnesium alloys by extrusion, rolling and / or forging is the production of suitable materials such. B. in the form of blocks, bolts or slabs. There are two main options for the production of bolts for extrusion:
In the first method, a bolt with a very large diameter can be cast, which can then be pressed with a high-performance extrusion press into round bolts with a diameter that corresponds to the recipient diameter. The segregation is reduced by the thermomechanical treatment.

A less complex process than this double extrusion is the production of the Bolts by sand, mold or continuous casting with a sufficiently large size Machining allowance. However, it is important to ensure that there are no severe segregations occur that are not or insufficient due to long homogenization times be balanced. Otherwise, the consequences could be poor compressibility and greater dispersion of the mechanical properties, in particular the ductility.

The cast bolts can first be subjected to heat treatment depending on the Alloy composition in z. B. 350 ° C in the range of 6 h to 12 h homogenized to eliminate segregations in the structure that z. T. heterogeneous structure too improve and increase the pressability. Then the homogenized bolts machined to the required dimensions.

Segregations can lead to uneven deformation and critical Extrusion conditions lead to cracks or local melting, which is bad Surface qualities can cause. With less well homogenized bolts is a unnecessarily high pressure required for extrusion. The homogenized bolts are then prepared for extrusion.

The extrusion of the magnesium alloys can be carried out in the same extrusion plants take place, which are used for the extrusion of aluminum alloys; either via direct as well as indirect extrusion. Only with the Tool design (die), the deformation behavior must be specifically taken into account. There are sharp-edged inlets, such as those used for aluminum alloys Avoid magnesium alloys, otherwise there is a risk of surface cracks. In  many cases z. B. for matrices of round profiles an entry angle of approx. 50 ° for Magnesium alloys used.

The most important parameter besides the extrusion temperature is the extrusion speed because it affects the properties and surface quality of the Extruded profiles significantly influenced. A high pressure also means a high one Extrusion speed, which is sought for economic reasons. A high Extrusion speed is usually with an even better surface quality connected. The pressability of the magnesium alloys is comparable to that heavy-duty aluminum alloys. A high extrusion speed is true Aimed from an economic point of view, this is not the case with magnesium alloys always feasible. Despite certain knowledge of the extrusion of Magnesium alloys usually need the parameters for extrusion in detail be worked out because there is a huge potential for optimization.

The extrusion is advantageously followed by a heat treatment. This Heat treatment is of particular interest for the lithium-containing alloys, while the other extruded modified alloys according to the invention by this heat treatment cannot be greatly improved. The semi-finished products can directed, e.g. B. by bending, pressing, pressure rolling, stretch drawing, deep drawing, High pressure forming or roll forming further deformed, e.g. B. by cutting, drilling, Milling, grinding, lapping, polishing machined, joined and / or z. B. by etching, painting or other coating can be surface-treated. With the invention Alloys can produce solid and extruded profiles in simple or complicated cross sections can be extruded without problems. Here semi-finished products can be improved or made from them or so that components can also be produced if necessary.

When joining, the semi-finished product or the component made therefrom or with it can pass through at least one low-heat joining process such. B. gluing, riveting, plugging, pressing, Pressing in, clinching, folding, shrinking or screwing and / or at least one heat-generating joining process such. B. composite casting, composite forging, Composite extrusion, composite rolling, soldering or welding, in particular Beam welding or fusion welding, with a similar or different type Semi-finished product or component can be connected. The different semi-finished product or component can likewise essentially of a magnesium alloy or of another alloy  or also consist of a non-metallic material. It can be the same or one have a different geometry than the semi-finished product or component according to the invention. The Joining methods can serve in particular to create a housing from several elements, to manufacture an apparatus, a system, a profile construction and / or a cladding.

Examples

The following examples according to the invention represent selected embodiments, without restricting the invention.

In the alloy designations used, A Al, E indicates at least one Rare earth element SE, whereby Y is also counted among the rare earth elements, M or MN Mn, S Si and Z Zn - usually with content in% by weight, unless otherwise is noted. With commonly used alloy information such. B. AZ31 will be through the numbers, as usual for the respective alloy, only in the order of magnitude specified, which can vary to a relatively wide extent, as is customary in the industry. In addition, at the starting alloy used in the examples and the ones produced with it modified alloys based on AZ have a low manganese content. All Examples showed traces of less than 0.1 wt% Cd, less than 0.05 wt% Cu, less than 0.04 wt% Fe and less than 0.003 wt% Ni.

The alloys were produced as high-purity, commercially available alloys or usually from high-purity starting alloys such as, for. B. AM, AZ or ZE alloys or by adding high-purity magnesium HP-Mg, a rare earth element-containing master alloy with a ratio of Nd to other rare earths including yttrium of 0.92, a zirconium-containing master alloy or / and alloyed by lithium. The standard alloys contained an Mn content of up to about 0.2% by weight. The alloys were melted in a steel crucible under the protective gas atmosphere of an Ar-SF ₆ mixture. The blanks required for the subsequent extrusion were cast in a cylindrical steel mold with machining allowance. The element contents achieved were checked spectroscopically. With all alloys, care was taken to ensure that the structure of the cast body is as homogeneous as possible and free of impurities, since this can have a sensitive effect on ductility. All alloys could be melted, poured off and processed into bolts without any problems.

The bolts were then turned to a diameter of 70 mm and to a length of 120 mm brought. The bolts were then subjected to homogenization treatment at e.g. B. 350 ° C exposed for 4 h or 12 h to eliminate segregations in the structure and the Increase pressability. Segregations can lead to uneven deformation and critical extrusion conditions lead to cracks or local melting, which can cause poor surface qualities. With less well homogenized bolts an unnecessarily high pressing pressure is required during extrusion. The homogenized bolts were then well prepared for extrusion.

The homogenized bolts were then brought up to the respective extrusion temperature heated, warmed up and extruded in a 400 t horizontal press. The The temperature of the bolt is therefore the temperature that the bolt has when it enters the Has extrusion.

The suitable ones were tested in systematic preliminary tests on the AZ31 reference alloy Extrusion parameters selected; on the extruded samples mechanical properties and the average grain sizes determined (Tables 1 and 2). The results of the preliminary tests essentially determined the test parameters of the subsequent attempts.

During the actual tests, several of the manufacturing parameters were systematically varied (Tables 3d / e). On the one hand, the die diameter was varied and became the Die speed and extrusion temperature kept constant, on the other hand the matrix geometry was kept constant and became the Die speed varied and finally the extrusion temperature varies depending on the alloy. The ram speed and the extrusion ratio gave the extrusion speed. With the help of such a parameter matrix an assessment of the influence of different forming conditions was possible.

It has been shown that usually high with the ductile magnesium alloys Extrusion speeds can be achieved. There are still tests no effort has been made to achieve the highest extrusion speeds achieve, but rather there is a clear potential, even significantly higher To be able to reach speeds. The degree of deformation characterizes the degree of Reduction in cross-section during forming and is used as the natural logarithm of the  Ratio of initial cross-section to cross-section specified after forming. He is therefore often correlated with the degree of dynamic recrystallization, where possible not a stronger growth of individual grains should occur, but one if possible fine-grain structure is sought, which is high for some magnesium alloys Ductility conditional. The more stable the structure of a magnesium alloy, the more fine-grained the structure becomes or remains when forming. It has been shown that the degree of deformation is advantageously at least 1.5, preferably at least 2, particularly preferably at least 2.5. If the degree of deformation is less than 1.5, the dynamic Very little recrystallization during forming. It would also have a grade of 3.5 or more can be selected in the tests.

All alloys, both the starting alloys and those by additives modified alloys could easily be used in a wide temperature, Form extrusion speed and extrusion ratio range. Bolts showed a good compressibility with a large scope in terms of pressing force and Pressing speed. The lower extrusion temperature is due to the insufficient plastic deformability below a temperature in the range of about 200 to 220 ° C. conditionally, the upper extrusion temperature is limited by the proximity to eutectic temperature and possibly through the initial formation of portions of a molten phase.

Depending on the extrusion conditions, the same result Alloy composition Differences in the structure of the samples. The occurred Extrusion pressures varied depending on the alloy used and the set one Extrusion parameters. Generally, a dynamic one occurred during extrusion Recrystallization and a reduction in the average grain size depending on the extrusion parameters and the alloy composition to different medium grain sizes.

The strength values determined on the cast and extruded samples were much higher than expected. The deformability was also surprising of these alloys very high. It was also surprising that the material properties of the modified alloys surprisingly little depending on the Extrusion conditions varied, which is advantageous for manufacturing. It was further Surprisingly, the impact energy of the ZE10 alloy was so high.  

Finally, the course of the extrusion that varied the course of the extrusion in the Characterized path diagram for alloys AZ, AZLi3.6 and AZLi6.8 with increasing lithium content differently than expected: it was shown with low lithium Addition worse behavior than without or with a higher lithium content. Some of the Alloys containing lithium gave an unexpectedly strong result with a high lithium content Dependence of the material properties on the type of heat treatment.

The extruded profiles were processed by milling and turning into round specimens (d ₀ = 5 mm, I ₀ = 5.d ₀ , small proportionality bar, according to DIN 50 125), pressure tests (d ₀ = 10 mm, I ₀ = 2.d ₀ , according to DIN 50 106), impact bending tests (10 × 10 × 55 mm, according to DIN 50 116) and notched impact bending tests (according to DIN 50 115). 5 of these samples were produced and tested per alloy and test. For all samples, the longitudinal direction was chosen so that it coincided with the direction of extrusion.

In the tensile test, tensile strength R _m , yield strength = yield strength R _P0.2 and elongation at break A or z. T. also determined the constriction of fracture in the tensile test at a tensile speed of 0.5 mm / min. Values of the compressive strength R _Dm , compression limit R _D0.2 and compression A _{D were obtained in the} compression test at a printing speed of 0.5 mm / min. The beginning of the plastic deformation (expansion or compression limit) was determined graphically. In addition, Brinell hardness measurements were carried out in accordance with DIN 50 351. All measurements took place at room temperature. The results of the mechanical determinations are summarized in Tables 3a-c and those of the structural investigations in Table 3d.

Grindings were made on selected samples, with respect to average grain size, Structural inhomogeneities as well as the type and distribution of the separated phases contained were assessed. This evaluation was used to further optimize the Manufacturing and processing parameters.

The variation of the extrusion parameters had a different influence on that Property profile of the extruded magnesium materials. Tendencies of Material properties of the different alloys depending on the manufacturing parameters can be seen from Tables 3e and 3f.  

The measurement results of the Brinell hardness determinations did not allow any special ones Statement. The Brinell hardness of the extruded samples was 7 to 22% higher than the cast samples. The hardness increased with the aluminum content.

The following manufacturing parameters were selected for the magnesium alloys containing Li

Production of the bolts: casting in tube molds at a casting temperature of 680 to 720 ° C for larger diameters and turning to usually 70 mm in diameter. The turned bolts were heat-treated at 350 ° C for 4 h (= homogenized).

Extrusion: Depending on the sample, an extrusion temperature in the range of 150 to 300 ° C and a time in the range of 50 for heating and warming the stud set up to 110 min. Preliminary tests were carried out with the AZ31 reference alloy (Tables 1 and 2). The preliminary tests allowed the preselection of the test parameters.

The specific extrusion tests were carried out in a 400 t extrusion press with direct extrusion. Depending on the sample, with a recipient diameter of 74 mm, a recipient temperature in the range from 180 to 259 ° C., a die diameter in the range from 15 to 18 mm, a compression ratio A / A ₀ in the range from 16.9 to 24.3, a degree of deformation ϕ = In (A ₀ / A) in the range from 2.8 to 3.2, a stamp speed in the range from 191 to 419 mm / min. an extrusion speed in the range of 3.2 to 9.0 m / min. a compression pressure at the start of the extrusion in the range from 15.2 to 24.3 MPa and a compression pressure at the end of the extrusion in the range from 10.0 to 14.8 MPa. Only a small part of the tests are shown in Table 3e.

The influence of extrusion parameters on the material properties of those containing lithium Alloys and their undoped base alloys were limited. He was with the Tensile strength was particularly low and increased beyond the elongation at break and compressive strength something to do with the work.

The extruded AM20Li3.6 alloy showed in comparison to the extruded alloy AM20 sometimes has higher mechanical properties (Tables 3a / c). Like the other extruded alloys, the addition of lithium led to a very strong one Increase in field work. The extruded AM20 alloy had a very high one elastic and a comparatively very low plastic part of the tension in the  extruded state (Table 3b). The addition of lithium doubled the corresponding plastic proportion.

The AZ31Li3.6 alloy was not subjected to tensile tests when cast characterized because the porosity of the samples was still a bit too high to be characteristic To provide statements. In the extruded state, this alloy had the highest Compressive strength values. With the AZ31 alloyed with lithium significantly higher toughness on notched impact samples as well as significantly higher Elongations at break determined as on the associated samples not alloyed with lithium, the highest values for the essentially two-phase alloy AZ31Li12.3 occurred. In contrast, the tensile strength decreased with the lithium content. The compressive strength was for the samples in the as-cast state proportional to the lithium content, for extruded ones However, samples are highest at medium lithium levels. Among the alloys in the The AZ31Li6.8 alloy showed an astonishingly high mean value at 122 MPa the yield strength. The deformability of the base grid of the AZ31 was Addition and the possibly modified elimination phase increased. The alloy AZ31Li6.8 showed, compared to the alloy AZ31Li3.6, a reduced tensile and Compressive strength, but a high compression limit and high elongation at break. The The addition of lithium improved the formability.

This had an effect on the lithium-containing alloys and their starting alloys Stress under pressure is different from that under tension: different from tensile strength took the compressive strength and sometimes the compression limit from AZ31 the lithium content of the AZ31Li3.6 alloy. The alloy AZ31Li6.8 showed due their high lithium content compared to the average of all samples in this series Mean values (Table 3a) the highest compression limit and fracture compression and a very high one Compressive strength. In this series the fracture compression of the samples was in the cast Condition higher than that of the extruded samples.

The cast alloy ZE10 had a very low elastic content, but almost on average high plastic part of the tension. With a lithium additive the elastic part increases significantly. On the other hand, the ZE10 alloy won at Extruding an extraordinarily high elastic portion of the tension during the plastic content remained approximately constant. For the alloys ZE10 and ZE10Li3.7 increased all mechanical properties of cast samples with the lithium  Content drastically. For the corresponding extruded samples, the mechanical properties with the exception of tensile strength and yield strength the lithium content. The alloy ZE10Li3.7 showed among the examined lithium containing magnesium alloys the highest values of the impact work, whereby due to Crash tests on deformation elements from the invention Magnesium alloys are assumed that the alloy MgLi15.5Al2.5Zn0.8 should have even higher impact and notch impact values than that Alloy ZE10Li3.7. Up to 140 J were obtained on individual samples of the ZE10Li3.7 alloy measured; other samples were taken through the abutment of the testing machine without to break completely, so that no measured value of the impact work could then be determined. The maximum applicable impact energy was 150 J.

The degree of deformation had a considerable influence on the impact work of those containing lithium Rehearse. The hammer work was with the lithium-containing magnesium alloys at one Degree of deformation ϕ of 2.83 often about 30 to 65% higher than for ϕ = 3.06 (Table 3f). At lower degrees of deformation and thus with smaller compression ratios resulted much higher values of impact work. This tendency occurred in the samples from unmodified Starting alloys and not or only with the samples alloyed with Ca or Zr weak on. The best impact work was performed on the samples containing lithium Forming temperatures of 200 to 250 ° C achieved. The forming speed (= Extrusion speed) had little effect on tensile strength and elongation at break.

The pressure-pressure curves during extrusion of the lithium-containing alloys at 200 ° C showed that with the alloy AZ31 + 12at% Li as well as AZ31 only with a higher one Pressing pressure, about 16 MPa, a flow of the material of the bolt occurred compared to the alloys AM20 + 12at% Li, AZ31 + 21at% Li and ZE10 + 12at% Li, in which the flow already occurred at around 12.5 MPa, but also a cheaper, lower pressure after a longer route was determined.

The examples demonstrated that the inventive Magnesium alloys for extrusion, but also in principle or as an alternative to extrusion, to other types of forming and others Deform due to their material properties.  

Table 1

Results of the preliminary tests to determine the extrusion parameters with the AZ31 alloy at an extrusion temperature of 400 ° C, a die diameter of 16 mm, recipient diameter of 74 mm and compression ratio of 1:21

Table 2

Influence of the compression ratio on the average grain sizes and the mechanical properties from the tensile test at an extrusion temperature of 400 ° C in the preliminary tests to determine the extrusion parameters

Tables 3 and 4 mean "casting = material in the as-cast state and" extr. "= Casting material, which is then homogenized and extruded (extruded) was reshaped, "B" = example according to the invention and "VB" = comparative example the state of the art.

Table 3a

Average values of the measurement results of the mechanical tests averaged over the various samples of the lithium-containing magnesium alloys and their starting alloys

Table 3b

Mean values of the values that can be determined from the stress-strain diagram of the tensile tests for lithium-containing magnesium alloys and their starting alloys. F = R _P02 yield stress = elastic part of the stress. V = yield strength ratio = F: Z. Rm = tensile stress. Z = elastic + plastic part of the tension

Table 3c

Highest mean values of the measurement results of the mechanical properties selected from various individual samples of the lithium-containing magnesium alloys

3d table

Structural components in the as-cast state after homogenization at 350 ° C for 4 h or after extrusion as well as predominantly occurring grain sizes (* = before hot aging)

Table 3e

Process parameters and average grain size for lithium-containing magnesium alloys and their starting alloys

Claims (28)

1. Magnesium alloy, the additives or traces of Cd less than 1.8% by weight and the traces of up to 0.1% by weight of Cu, up to 0.05% by weight of Fe and up to 0.005% by weight. % Can contain Ni, characterized in that their Li content 0.5 to 20% by weight, their tensile strength at least 227 MPa, their impact energy measured on non-notched samples at least 72 J and their elongation at break measured on tensile samples at least 26 % is. 2. Magnesium alloy, the additives or traces of Cd less than 1.8 wt .-% and the traces of up to 0.1% by weight of Cu, up to 0.05% by weight of Fe and up to 0.005 Wt .-% Ni, characterized in that their Li content 0.5 to 20% by weight that their tensile strength is at least 250 MPa, that their impact work Measured on notched samples at least 72 J and that their elongation at break measured at least 21% on tensile samples. 3. Magnesium alloy, the additives or traces of Cd less than 1.8 wt .-% and the traces of up to 0.1% by weight of Cu, up to 0.05% by weight of Fe and up to 0.005 Wt .-% Ni, characterized in that their Li content 0.5 to 20% by weight that their tensile strength is at least 276 MPa, that their impact work Measured on notched samples at least 70 J and that their elongation at break measured on tensile samples is at least 18%. 4. Magnesium alloy, the additives or traces of Cd less than 1.8 wt .-% and the traces of up to 0.1% by weight of Cu, up to 0.05% by weight of Fe and up to 0.005 Wt .-% Ni, characterized in that in addition to Mg 0.5 to 10 wt .-% Al and 0.1 to 3 wt .-% Mn contains that their tensile strength at least 200 MPa that their elongation at break measured on tensile specimens at least 12% that their compressive strength is at least 240 MPa and that their Impact energy measured on unslotted samples is at least 25 J.   5. Magnesium alloy, the additives or traces of Cd less than 1.8 wt .-% and the traces of up to 0.1% by weight of Cu, up to 0.05% by weight of Fe and up to 0.005 Wt .-% Ni, characterized in that in addition to Mg 0.5 to Contains 10 wt .-% Al, 0.1 to 3 wt .-% Mn and 0.5 to 20 wt .-% Li and that their elongation at break measured on tensile specimens is at least 12%. 6. Magnesium alloy, the additives or traces of Cd less than 1.8 wt .-% and the traces of up to 0.1% by weight of Cu, up to 0.05% by weight of Fe and up to 0.005 Wt .-% Ni, characterized in that in addition to Mg 0.5 to 10 wt .-% Al, 0.1 to 3 wt .-% Zn and 0.5 to 20 wt .-% Li contains that their Tensile strength at least 210 MPa that their elongation at break measured at Tensile tests at least 20% and that their impact work measured at unnotched samples is at least 90 J. 7. Magnesium alloy according to at least one of claims 1 to 6, characterized characterized in that they contain at least one rare earth element SE including Y of at least 0.1 wt .-% SE each, the Total content of all rare earth elements is up to 1% by weight. 8. Magnesium alloy according to at least one of claims 1 to 7, characterized characterized in that they contain at least one element from the Group of cerium, praseodymium, neodymium, samarium, gadolinium, ytterbium, Has lanthanum and yttrium. 9. Magnesium alloy, the additives or traces of Cd less than 1.8 wt .-% and the traces of up to 0.1% by weight of Cu, up to 0.05% by weight of Fe and up to 0.005 Wt .-% Ni, characterized in that in addition to Mg 0.1 to 3 % By weight of Zn and 0.1 to 1% by weight of at least one rare earth element or / and Y contains that their tensile strength is at least 230 MPa, that their Impact work measured at least 50 J and that their notched specimens Elongation at break measured on tensile specimens is at least 20%. 10. Magnesium alloy, the additives or traces of Cd less than 1.8 wt .-% and the traces of up to 0.1% by weight of Cu, up to 0.05% by weight of Fe and up to 0.005 Wt .-% Ni, characterized in that in addition to Mg 0.1 to 3 % By weight of Zn each 0.1 to 1% by weight of at least one rare earth element  including Y and 0.5 to 20 wt .-% Li and that their elongation at break measured at least 20% on tensile samples. 11. Magnesium alloy according to at least one of the preceding claims, characterized in that it consists essentially of an alloy, which is selected from the group of alloys based on AM, AZ, FZ, MA, ZA or ZE and the addition of lithium, manganese, aluminum, calcium, Strontium, zinc, zirconium or at least one rare earth element included May contain yttrium. 12. By at least one addition from the group of lithium, calcium, strontium, Zirconium and at least one rare earth element SE including yttrium modified magnesium alloy, the additions or traces of Cd less than 1.8 % By weight and the traces of up to 0.1% by weight of Cu, up to 0.05% by weight of Fe and can contain up to 0.005% by weight of Ni, characterized in that their Compressive strength has at least 260 MPa that their impact work is measured on notched specimens at least 72 J and that their elongation at break was measured tensile tests is at least 18%. 13. Magnesium alloy according to at least one of the preceding claims, characterized in that it has a plastic portion of the tension determined in the tensile test according to the stress-strain diagram from the Difference between tensile stress and yield stress of at least 50 MPa having. 14. Magnesium alloy according to at least one of the preceding claims, characterized in that it has a structure with an average grain size of has a maximum of 50 µm. 15. Magnesium alloy according to at least one of the preceding claims, characterized in that it is extruded, rolled or / and forged is and a dynamically recrystallized fine-grained structure and a content of Elimination phases of no more than 5 vol.% 16. Process for producing a semi-finished product from a magnesium alloy at least one of the preceding claims or one with or from it  manufactured component or / and composite with at least one Semi-finished product or component, characterized in that the alloy at Temperatures in the range of 550 to 900 ° C is melted and that one or several moldings produced by casting without or with additional pressure and possibly also be heat-treated afterwards. 17. A method for producing a semi-finished product from a magnesium alloy or of a component or / and composite produced therewith or therefrom Claim 16, characterized in that the molded body is processed if necessary, Thereafter, if necessary, heat-treated, then reshaped, especially by Extrusion, forging and / or rolling, and then optionally heat-treated becomes. 18. A method for producing a semi-finished product from a magnesium alloy or of a component or / and composite produced therewith or therefrom Claim 16 or 17, characterized in that the to be formed Shaped bodies at temperatures in the range from 300 to 420 ° C for 0.5 to 48 h is homogenized, preferably in the range from 330 to 380 ° C. for 2 to 24 h. 19. A method for producing a semi-finished product from a magnesium alloy or of a component or / and composite produced therewith or therefrom at least one of claims 16 to 18, characterized in that the Molded articles to be formed at extrusion temperatures in the range from 100 to 450 ° C is extruded. 20. A method for producing a semi-finished product from a magnesium alloy or of a component or / and composite produced therewith or therefrom at least one of claims 16 to 19, characterized in that with a pressing speed in the range of 0.5 to 20 m / min is extruded. 21. A method for producing a semi-finished product from a magnesium alloy or of a component or / and composite produced therewith or therefrom at least one of claims 16 to 20, characterized in that the Shaped body, the semi-finished product or component after forming at temperatures is stored in the range from 50 to 200 ° C.   22. A method for producing a semi-finished product from a magnesium alloy or of a component or / and composite produced therewith or therefrom at least one of claims 16 to 21, characterized in that the reshaped molded body or the reshaped semi-finished product is further deformed, e.g. B. by stretch drawing, deep drawing, bending, pressing, pressure rolling, Roll forming or / and straightened. 23. A method for producing a semi-finished product from a magnesium alloy or of a component or / and composite produced therewith or therefrom at least one of claims 16 to 22, characterized in that the Shaped body, the semi-finished product or component is processed, for. B. by turning, Milling, drilling, cutting, tumbling, punching, deburring, shaping, grinding, Lapping or / and polishing. B. by degreasing or de-oiling or / and surface treatment is carried out e.g. B. by pickling and / or coating. 24. A method for producing a semi-finished product from a magnesium alloy or of a component or / and composite produced therewith or therefrom at least one of claims 16 to 23, characterized in that at least one molded body, semi-finished product and / or component by at least one low-heat joining processes such. B. gluing, riveting, plugging, pressing, Pressing in, clinching, folding, shrinking or screwing or / and at least a heat-generating joining process such. B. composite casting, Composite forging, composite extrusion, composite rolling, soldering or Welding, in particular beam welding or fusion welding, with at least one similar or different type of molded article, semi-finished product or Component is connected. 25. Semi-finished product made of a magnesium alloy or with it or made therefrom Component or composite with at least one such semi-finished product or component, characterized in that it is a magnesium alloy according to at least is one of claims 1 to 15. 26. Semi-finished product made of a magnesium alloy or with or made therefrom Component or composite with at least one such semi-finished product or component,  characterized in that it according to at least one of claims 16 to 24 is made. 27. Use of a semi-finished product made of a magnesium alloy according to at least one of claims 1 to 15 or one produced therewith or from it Component or / and a composite with at least one such semi-finished product or / and component as gear housing, steering wheel skeleton, wishbone, Frame element, element of vehicle cell or vehicle outer skin, Cockpit support, housing, base element, cover, tank element, fuel filler flap, Bracket, support, bracket, angle, hollow profile, tube, deformation element, Crash element, crash absorber, impact absorber, impact shield, impact carrier, small parts such as as a gear, as an impeller and other types of wheels, as welded Profile constructions, for the vehicle body, for seat, window or / and Door frame, as a semi-finished product, component or composite on or in the automobile or Plane. 28. Use of a semi-finished product made of a magnesium alloy, one with it or component made therefrom and / or a composite with at least one such semi-finished product and / or component - manufactured according to at least one of the Claims 16 to 24 - as a gear housing, steering wheel skeleton, wishbone, Frame element, element of vehicle cell or vehicle outer skin, Cockpit support, housing, base element, cover, tank element, fuel filler flap, Bracket, support, bracket, angle, hollow profile, tube, deformation element, Crash element, crash absorber, impact absorber, impact shield, impact carrier, small parts such as as a gear, as an impeller and other types of wheels, as welded Profile constructions, for the vehicle body, for seat, window or / and Door frame, as a semi-finished product, component or composite on or in the automobile or Plane.