ALUMINIUM ALLOYS IN THE AEROSPACE INDUSTRY
AEROSPACE ALUMINIUM ALLOYS
MATMATCH
ALUMINIUM ALLOYS IN THE AEROSPACE INDUSTRY
Aluminium has a long and successful history in the aerospace industry . As far back as the 19th century , Count Ferdinand Zeppelin made the frames of his iconic airships from it . Aluminium was chosen as it is lightweight , strong , and has a high resistance to corrosion . In this article , Marta Danylenko , marketing manager at online materials database Matmatch , explains the common alloys used in aerospace engineering and their applications , as well as some less wellknown ones , and what the future holds for aerospace materials .
A brief history
The Wright brothers chose aluminium for the cylinder block and other engine parts for their first manned flight in 1903 . It was also the first time an aluminium alloy had been heat-strengthened . This discovery prompted the preference for aluminium in aerospace engineering . Over the years , the aerospace industry has become more demanding in what it needs from materials . The advent of jumbo jets and long-haul international flights meant that the shell and engine parts had to be extremely durable and resistant to fatigue . This has led to the development and use of many different types of aluminium alloys .
Commonly used aluminium alloys in the aerospace industry
Second only to AA 2024 in terms of its popularity in aerospace engineering , AA2014 is a strong and tough metal and is suitable for arc and resistance welding . However , it has poor corrosion resistance , and for that reason , it is often found in the internal structure or framework of aircraft rather than the shell .
Aluminium alloy 2024 is probably the most widely used alloy for aircraft . It was developed after experiments allowing small amounts of cold deformation and a period of natural ageing led to an increased yield strength . 2024 is a high-grade alloy with excellent fatigue resistance . It ’ s used primarily in sheet forms such as for the fuselage and wings due to its high tensile strength of roughly 470 MPa . Of the nonheat treatable grades of alloy , AA 5052 provides the highest strength and is highly ductile , so it can be formed into a variety of shapes including engine components and fittings . It is also highly corrosion resistant .
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AA 6061 alloy is very common in light aircraft , especially homemade ones . It ’ s easily welded and manipulated , is very light and fairly strong , making it ideal for fuselage and wings . AA 7050 has high corrosion resistance and maintains strength in wide sections . This makes it more resistant to fractures than other alloys . It ’ s commonly used in wing skins and fuselage , especially in military aircraft . AA 7068 is the strongest alloy available today . Combined with its low mass , it is perfect for military aircraft that need to stand up to tough conditions and attacks .
With similar strength properties to steel due to its high levels of Zinc , AA 7075 has excellent fatigue resistance . It can be machined easily which meant it was a popular choice for fighter planes in World War II , including the Mitsubishi A6M Zero fighter used by the Japanese Imperial Navy on their carriers between 1940 and 1945 . It is still used frequently in military aircraft to this day .
Less common aluminium alloys in the aerospace industry
If you need an aluminium alloy that provides maximum strength at elevated temperatures , AA 2219 is the best bet . It was used for the external fuel tank of the first successfully launched space shuttle , Columbia .
It has good weldability , but the welds need heat-treating to preserve resistance against corrosion .
AA 6063 is mainly used for aesthetic and architectural finishes and can be found in the finer details of an aircraft . It is used primarily for intricate extrusions . AA 7475 is highly resistant to fracture and fatigue . Due to its toughness , it is sometimes found in fuselage bulkheads of larger aircraft .
The future of aluminium alloys in aerospace
Industry experts are positive about the future of aluminium alloys in aerospace . It is projected that demand for aluminium will double over the next decade . By 2025 , there will be a global demand of 80 million tonnes . For this reason , the aerospace industry is increasingly looking to recycled alloys to satisfy their high demand . There is also a push for innovation in the materials used , as well as the design structure of aircraft .
As developing countries become more involved in the aerospace industry , and with increased investment , there will be further innovation in aluminium alloys over the years to come .
If you ’ re looking for a tool to compare engineering material properties , Matmatch ’ s online database helps you to find materials , compare them side-by-side and choose materials that perfectly fit the intended application , the budget for the project and your goals .
www . matmatch . com