What Are Aluminum Alloys Used For?
You must be reading this on your mobile phone or laptop. Did you know it is made with aluminum or aluminum alloy?
Aluminum Al is the third most abundant element on the planet and so versatile. It can be used in any industry in the world for a variety of purposes. Aluminum is the preferred metal of choice because of its qualities. Its weight, strength, durability, malleability, and high-level resistance to corrosion, precipitation, and exfoliation are just some of the qualities that set aluminum apart from other metals. However, aluminum also can combine with other metals like silicon, copper, zinc, and manganese to form stronger, ductile, yet still retain its original property. When aluminum combines with these metals, it becomes aluminum alloys.
What are aluminum alloys?
As mentioned above, when another metal is added to pure aluminum to alter its properties, this is an alloy. Aluminum alloys are important for so many reasons. Aluminum in its pure state will experience some brittleness at some degree of coldness or hotness. However, when combined with the other metals of stronger covalent bonds, its property is enhanced, especially the tensile strength. This makes aluminum alloys useful in all industries even in oblivious settings like the glass industry.
| Alloy Number | Alloy Metal |
|---|---|
| 1XXX | Pure aluminum (no additional metal) |
| 2XXX | Copper and aluminum |
| 3XXX | Manganese and aluminum |
| 4XXX | Silicon and aluminum |
| 5XXX | Magnesium and aluminum |
| 6XXX | Silicon and magnesium + aluminum |
| 7XXX | Zinc aluminum |
| 8XXX | Aluminum mixed with any metal |
Now, the four digits are read as such
The first digit, which is 1, 2 3, 7, or 8 indicates the type of alloy metal added to pure aluminum. In the case of 1XXX, it is unalloyed hence pure aluminum with a purity of 99.00 % or higher.
The second digit, taking this as an example 1Xxx – the blue X, indicated the modification of the alloy used in the combination. For example, the alloy 5657 means the alloy is made from aluminum, silicon, and magnesium together.
The last 2 digits 1XXX – the two blue X are used to correctly indicate the specific alloy and enable easier identification. However, the last two digits in 1XXX signify the purity level of aluminum. For example, 1100 is 99.00 % pure aluminum and 1170 is 99.70 % pure aluminum.
Types of aluminum alloys, properties and uses
From the table above there are 8 classes of aluminum alloys, namely;
1XXX Series Alloys
Pure 99.9% 1xxx aluminum
Also referred to as pure aluminum metal, alloys in this category must be 99 % and above pure. They are selected for their high tensile strength (10 -27 KSI), weldability, excellent resistance to corrosion, and high conductivity to heat and electricity. Although they have excellent qualities, their weak structural property limits their use in producing high-stress items. Most common alloys in this series are:
- 1050 – This aluminum alloy has 99.50% purity and can be work-hardened increased the strength and malleability. This also allows 1050 to be extruded or shaped into different forms. It is commonly made into coils and used in the food, brewing, and chemical industries. It is also used in making hoses and fireworks powder
- 1060 – Has 99.60% purity, these alloys of universal use. It is highly resistant to corrosion and easily workable. It is used in making chemical equipment.
- 1070 – This is top-grade aluminum with exceptional malleability, resistance to corrosion but not the toughest of the bunch. It is super light and conducts heat and electricity seamlessly. It is used in everyday essentials like lighting fixtures, dissolved wiring, and other forms of conductors.
- 1100 – It is not the hardest but is workable with high resistance to corrosion. It is used for making spare parts and utensils for the food industry. It can be spun welded, made into sheets, coils for a variety of purposes like concave vessels, printing plates, reflectors, nameplate, etc.
Finish 2xxx Aluminum Alloy
This heat treatable alloy has copper as the main element to intensify the strength, toughness, and performance with a tensile strength of up to 62 ksi. It is resistant to atmospheric corrosion, temperature variation, and used in aerospace manufacturing for making parts and spare parts. Some commonly used alloys are
- 2219 – Their ability to maintain structural stability over a wide range of temperatures +270 -600° centigrade. They are also precipitation hardened and resistant to stress corrosion cracking in T8 hence used in making the oxidizer tank for welding space rockets, the body of supersonic aircraft.
- 2319 – Is used as welding filler wire for alloy 2219.
- 2618 – used in aircraft engine parts, pistons and model forging
- 2A01, 2A02, 2A06, 2A10, 2A11, 2A12, 2A14, 2A16, 2A17, 2A50, 2A60, 2A70, 2A80, and 2A90 are alloys that operate over temperatures between 100 – 300 degrees centigrade. They are used to make different aerospace parts like the propeller, blades, structural rivets, aircraft wings, bolts, complex designs, and structure for aircraft or transportation tools.
2XXX Series Alloys
3XXX Series Alloys
Cooking Utensils
Alloys in this series have manganese mixed with pure aluminum. They are non-heat-treatable with a tensile strength of 16 to 41 ksi. They are moderately strong, easily formed into other shapes and designed, excellent resistance to corrosion, and suited for use in situations with high temperatures.
Commonly used alloys in this series are:
- 3003 – These are highly pure aluminum alloys with great workability, weldability, and high corrosion resistance better than 1XXX series alloy. It is used in storage units, tanks of storing liquid products, cooking utensils, pipes, and high-pressure vessels from sheet metals. 3003 aluminum sheets have over 1% manganese used in tanks, storage units and in metal work.
- 3004 – Have a higher strength than the 3003 alloy and high corrosion resistance hence used in sheet metal work pieces, aluminum cans, construction tools, chemical products, and household lamps.
- 3105 – This alloy has a commercial application on essential everyday items like bottle cover, gutter, downpipe, room partition, sheet forming parts, and many more everyday items.
- 3A21 – this is the strongest in this series and used in making rivet wire, industrial equipment, building material, and aircraft fuel tanks and in the food industry.
Generally, aluminum alloys fall into two categories – heat treated and non-heat treated, but 4xxx aluminum alloys have products that fall into either category. Alloys in this class contain silicon of less than 1% to over 20 percent. 4043 is the most used alloys in this series; they have high weldability, resistance to corrosion, formability, and wear resistance.
Other alloys are 4343 & 4045 used in brazing & welding materials, rods, coil, pipes, and tubes. They are also great for extrusion and forging due to their surface hardness and low melting point expands their usage in various industries.
4XXX Series Alloys
5XXX Series Alloys
5xxx alloys for making car body and parts
Magnesium is the primary alloying metal in this mix. It is a non-heat-treatable alloy used across all industries from transportation, construction, and storage tanks. 5XXX alloys have high tensile strength, resistance to corrosion, malleability, and formability.
Examples of alloys in this series are:
- 5005– Has similar strength as 3003 but with a brighter anodic oxide and consistent hue than the 6060. Its high resistance to corrosion and conductivity makes it useful in cookers, building decoration, conductors, and more.
- 5050, 5052 5056, 5083 and the 5086 – these are medium tensile strength with high fatigue strength and great weldability used in refrigerator sheet, pipes and pipelines, aircraft tanks, nails, cables, irrigation pipes, transportation parts, missiles components, brackets, TV tower, pressure vessels, and rivets. 5052 aluminum sheet properties and high resistance to corrosion makes them applicable in marine and water industry.
- 5154, 5182, and 5252 are of higher tensile strength and used in pressure vessels, storage tanks, ship parts, offshore facilities, reinforcement sheet, and welded structures.
- Other magnesium alloys in this category are 5254, 5356, 5454, 5456, 5457, 5652, and 5657 used in pressurized containers, electrodes, armor plates, chemical products, and ship parts.
- Magnesium-aluminum alloys also have medium tensile strength like 5A02, 5A03, 5A05, 5A06, and 5A12 used in welded structures, aircraft tanks; bulletproof deck and cold die forging parts.
These series alloys are malleable, durable, and workable with high resistance to corrosion. It is also one of the most versatile alloys used in a variety of industries.
The alloys in this series combine magnesium and silicon to form a magnesium silicide used in the welding fabrication industry, vehicle making, architecture, construction and added as reinforcement to many elements. The 6XXX series alloys are common as extrusion and combine with most metals to form solid and durable materials.
Common alloy in this category are:
- 6005 are predominately extrusion forms used as structural parts, pipes, electronic antennas, and ladders.
- 6009 and 6010 are mainly aluminum sheets used in car manufacturing and automobile body.
- 6061 is the most common alloy in this series. Its high resistance to corrosion and strength makes it a suitable option for mobile phone casing, trucks, pipes, trams, ships, and mechanical parts. 6061 aluminum sheets great resistance to corrosion, cracking, temperature changes and formability makes them idea for framing, base plates, automotive industries, and in making a wide range of products.
- 6063, 6066, and 6070 alloys are excellent extrusion and forging materials for benches, furniture, fences, building profiles, the automotive industry, and a variety of welding works.
- 6101, 6151, 6201, 6205, and 6262 – alloys in this category have high tensile strength, good resistance to corrosion, and high impact resistance extrusions. They don’t require excess workability and great in strength bars, machine parts, die forging crankshaft parts, cooling equipment, and wires.
- 6351, 6463, and 6A01 – workable, malleable, tough alloys with high resistance to corrosion make them the preferable alloys for die forging, aircraft engine parts, pipes for transporting liquids like water and oil, appliances and building profiles an automotive decoration.
6XXX Series Alloys
7XXX Series Alloys
Used in making aircraft parts
These are heat treatable, high performance, high strength zinc alloy for use in areas where toughness, ruggedness, and pressure is required. Although zinc is the main alloying metal, other metals like chromium and magnesium are added in small quantities to boost the tensile strength and application.
Common alloys in this series are:
- 7005 –great for welding structures and used in holding materials that cannot solidify after welding. Their high tolerance to heat and temperature variation enable them to be used in making containers, rods, sports equipment, and trusses.
- 7039, 7049, 7050, 7075, 7175, 7178, and 7475 consist of high tensile strength alloys with high resistance to corrosion, cracking, stress, pressure, and fatigue. They are used in cryogenic equipment, fire pressure vessel, storage containers, aircraft parts, military equipment and die forging. The 7049 has the same 7079-T6 with extra toughness and used in missile parts, extruders, and landing hydraulic cylinder.
- 7072 is another versatile alloy in this series. It has moderate strength and is easily made into thin sheets and foil used in the air conditioner and cladding of pipes. It is stronger and a better choice than 2219, 3030, 3004, 5050, 5052, 5154, 6061, 7075, 7475, and 7178.
- 7A04 – is a lightweight but tough alloy. Its anti-corrosion and fatigue resistance make it the alloys for producing aircrafts parts like landing gears, screws, frames, and wing ribs.
- 7150 – This is an aircraft alloy with extensive use in aerospace mechanics. It is better than the 7050 in strength and resistance to corrosion. In the T651 condition, it has 10 – 15 % stronger than the 7075, fracture toughness of 10% with a similar anti-SCC.
- 7055 – Has high tensile strength, fracture toughness, and corrosion resistance, making it the alloy of choice in cargo track, upper wing, rail, girder, and keel. It is 10 % stronger than in 7150.
Bottle Caps
Alloys in this series are the stronger as they consist of other metals in different proportions. The alloys have versatile applications with low density, high corrosion resistance, lightweight, and an excellent replacement for copper.
Common alloys in this series are:
- 8011 and 8079 – this light, malleable, and crack resistance alloys are used in the food packaging and pharmaceutical industry. They are used in aluminum foils, food containers, bottle caps, aluminum caps, etc. The 18 temper quality of 8079 increases its performance quality, especially for use in pharmaceutical foil.
- 8021 has similar properties with 8011 and 8074, but its tensile strength and stretchability expand its uses. Furthermore, it has a level surface area with minimal pinholes and spectacular design. 8021 alloys are used in making soft lunch bags, lunch boxes, food packaging foil, and battery tab materials.
8XXX Series Alloys
Aluminum alloys with their properties are the most used metals in the world today. Whether it is manufacturing, pharmaceutical, food, aerospace, home décor, fittings and fixtures, this light, malleable, stretchable, and shiny metal are super versatile. However, their ability to conform and different designs, shapes, and sizes are one reason why they are the best in all areas. Aluminum diamond sheets are another common material made from aluminum alloys. These sheets have raised patterns that increase the traction and friction onto smooth and even surfaces that aluminum possesses. Furthermore, these sheets are great at docks, where heavy lifting is done, etc.
