 | This article includes a list of references, related reading or external links, but its sources remain unclear because it lacks inline citations .(September 2020) |
Mag-Thor is the common name for a range of magnesium (Mg) alloys containing thorium (Th) that are used in aerospace engineering.
These alloys commonly contain manganese and zinc, but there are other combinations known. Some common alloys are named HK31, HM21, HM31, HZ32, ZH42, ZH62; where the "H" indicates that the alloy contains thorium. Magnesium alloy names are often given by two letters following by two numbers. The two letters indicate the main elements present in the alloy where A = aluminum, Z = zinc, M = manganese, S = silicon, etc. the numbers tell percentage compositions of the two elements. So, AZ31 would indicate that there is 3% aluminum and 1% zinc in the alloy.
Magnesium-thorium alloys have been used in several military applications, particularly in missile construction. The most noted example of this is the ramjet components in the CIM-10 Bomarc missile and Lockheed D-21 drone, which implemented thoriated magnesium in their engine construction. This is due to thoriated magnesium alloys being lightweight, having high strength, and creep resistance up to 350 °C. But, these alloys are no longer used due to radiation concerns involving thorium's radioactivity. This has resulted in several missiles being removed from public display. Similarly, the structure of the Equipment and Retro-Rocket Modules of the Gemini spacecraft (the white-painted portions) were made of thoriated magnesium for their strength-to-weight ratio and thermal properties. These were not part of the inhabited cabin, though the radiator tubing, whose silicone coolant flowed through the cabin, was also made of the same material. All examples burned up in the atmosphere upon reentry.
Another concern for the thoriated magnesium alloys is the low melting point and rapid oxidation of the metal. This can result in dangerous flash fires during the production of the alloys. Additionally, thorium-free magnesium alloys have been developed that exhibit similar characteristics to mag-thor, causing currently used magnesium-thorium alloys to be cycled out of use.
Magnesium alloys are mixtures of magnesium with other metals, often aluminium, zinc, manganese, silicon, copper, rare earths and zirconium. Magnesium alloys have a hexagonal lattice structure, which affects the fundamental properties of these alloys. Plastic deformation of the hexagonal lattice is more complicated than in cubic latticed metals like aluminium, copper and steel; therefore, magnesium alloys are typically used as cast alloys, but research of wrought alloys has been more extensive since 2003. Cast magnesium alloys are used for many components of modern automobiles and have been used in some high-performance vehicles; die-cast magnesium is also used for camera bodies and components in lenses.
Aluminium alloys are alloys in which aluminium (Al) is the predominant metal. The typical alloying elements are copper, magnesium, manganese, silicon, tin and zinc. There are two principal classifications, namely casting alloys and wrought alloys, both of which are further subdivided into the categories heat-treatable and non-heat-treatable. About 85% of aluminium is used for wrought products, for example rolled plate, foils and extrusions. Cast aluminium alloys yield cost-effective products due to the low melting point, although they generally have lower tensile strengths than wrought alloys. The most important cast aluminium alloy system is Al–Si, where the high levels of silicon (4.0–13%) contribute to give good casting characteristics. Aluminium alloys are widely used in engineering structures and components where light weight or corrosion resistance is required.
7075 aluminium alloy (AA7075) is an aluminium alloy, with zinc as the primary alloying element. It has excellent mechanical properties and exhibits good ductility, high strength, toughness, and good resistance to fatigue. It is more susceptible to embrittlement than many other aluminium alloys because of microsegregation, but has significantly better corrosion resistance than the alloys from the 2000 series. It is one of the most commonly used aluminium alloys for highly stressed structural applications and has been extensively used in aircraft structural parts.
2024 aluminium alloy is an aluminium alloy, with copper as the primary alloying element. It is used in applications requiring high strength to weight ratio, as well as good fatigue resistance. It is weldable only through friction welding, and has average machinability. Due to poor corrosion resistance, it is often clad with aluminium or Al-1Zn for protection, although this may reduce the fatigue strength. In older systems of terminology, 2XXX series alloys were known as duralumin, and this alloy was named 24ST.
AA 6063 is an aluminium alloy, with magnesium and silicon as the alloying elements. The standard controlling its composition is maintained by The Aluminum Association. It has generally good mechanical properties and is heat treatable and weldable. It is similar to the British aluminium alloy HE9.
5083 aluminium alloy is an aluminium alloy with magnesium and traces of manganese and chromium. It is highly resistant to attack by seawater and industrial chemicals.
AA 2519 is an aluminium alloy principally containing copper (5.3–6.4%) as an alloying element. It also contains 0.25% silicon, 0.30% iron, 0.10–0.50% manganese, 0.05–0.40% magnesium, 0.10% zinc, 0.02–0.10% titanium, 0.05–0.15% vanadium, 0.10–0.25% zirconium, 0.40% silicon-iron compounds, and up to 0.15% trace elements. The density of 2519 aluminium is 2820 kg/m3. It was first registered in 1985, in the United States.
AA 2319 is an aluminium alloy principally containing copper (5.8–6.8%) as an alloying element. It also contains ≤0.20% silicon, ≤0.30% iron, 0.20–0.40% manganese, ≤0.02% magnesium, ≤0.10% zinc, 0.10–0.20% titanium, 0.05–0.15% vanadium, 0.10–0.25% zirconium, ≤0.0003% beryllium and up to 0.15% trace elements. The density of 2319 aluminium is 2840 kg/m3. This alloy was first registered in 1958, in the United States.
2014 aluminium alloy (aluminum) is an aluminium-based alloy often used in the aerospace industry.
7068 aluminium alloy is one of the strongest commercially available aluminium alloys, with a tensile strength comparable to that of some steels. This material, also known as an aircraft alloy, is heat treatable.
5454 aluminium alloy is an alloy in the wrought aluminium-magnesium family. It is closely related to 5154 aluminium alloy. As an aluminium-magnesium alloy, it combines moderate-to-high strength with excellent weldability. Like 5154, 5454 aluminium is commonly used in welded structures such as pressure vessels and ships. As a wrought alloy, it can be formed by rolling, extrusion, and forging, but not casting. It can be cold worked to produce tempers with a higher strength but a lower ductility. It is generally not clad.
5456 aluminium alloy is an alloy in the wrought aluminium-magnesium family. While it is closely related to 5356 aluminium alloy, it is used in structural applications, like most other aluminium-magnesium alloys, and not as filler for welding. As a wrought alloy, it can be formed by rolling, extrusion, and forging, but not casting. It can be cold worked to produce tempers with a higher strength but a lower ductility. It is susceptible to exfoliation corrosion when held at temperatures above 65 °C (150 °F) for extended periods of time.
6005A aluminium alloy is an alloy in the wrought aluminium-magnesium-silicon family. It is closely related, but not identical, to 6005 aluminium alloy. Between those two alloys, 6005A is more heavily alloyed, but the difference does not make a marked impact on material properties. It can be formed by extrusion, forging or rolling, but as a wrought alloy it is not used in casting. It cannot be work hardened, but is commonly heat treated to produce tempers with a higher strength at the expense of ductility.
6060 aluminium alloy is an alloy in the wrought aluminium-magnesium-silicon family. It is much more closely related to the alloy 6063 than to 6061. The main difference between 6060 and 6063 is that 6063 has a slightly higher magnesium content. It can be formed by extrusion, forging or rolling, but as a wrought alloy it is not used in casting. It cannot be work hardened, but is commonly heat treated to produce tempers with a higher strength but lower ductility.
6105 aluminium alloy is an alloy in the wrought aluminium-magnesium-silicon family. It is one of the least common of the alloys in this series. While most wrought aluminium alloys are covered by multiple standards, 6105 is only dealt with in ASTM B221: Standard Specification for Aluminum and Aluminum-Alloy Extruded Bars, Rods, Wire, Profiles, and Tubes. It is formed by extrusion, and supplied in heat treated form. It can alternately referred to by the UNS designation A96105.
6162 aluminium alloy is an alloy in the wrought aluminium-magnesium-silicon family. It is related to 6262 aluminium alloy in that Aluminum Association designations that only differ in the second digit are variations on the same alloy. It is similar to 6105 aluminium alloy, both in alloy composition and the fact that it is only really used in extrusions. However, as a wrought alloy, it can also be formed by rolling, forging, and similar processes, should the need arise. It is supplied in heat treated form. It can be referred to by the UNS designation A96162, and is covered by the standard ASTM B221: Standard Specification for Aluminum and Aluminum-Alloy Extruded Bars, Rods, Wire, Profiles, and Tubes.
6262 aluminium alloy is an alloy in the wrought aluminium-magnesium-silicon family. It is related to 6162 aluminium alloy, but sees much more widespread use. It is notably distinct from 6162, and most other aluminium alloys, in that it contains lead in its alloy composition. It is typically formed by extrusion, forging, or rolling, but as a wrought alloy it is not used in casting. It can also be clad, but that is not common practice with this alloy. It cannot be work hardened, but is commonly heat treated to produce tempers with a higher strength but lower ductility.
The 6463 aluminium alloy is an aluminium alloy in the wrought aluminium-magnesium-silicon family. It is related to 6063 aluminium alloy, but unlike 6063 it is generally not formed using any processes other than extrusion. It is commonly heat treated to produce tempers with a higher strength but lower ductility. Like 6063, it is often used in architectural applications.
7022 aluminium alloy is an alloy in the wrought aluminium-zinc family. It is one of the more complex grades in the 7000 series, with at least 87.85% aluminium by weight.