With so many excellent and versatile aluminum alloys on the market to choose from, manufacturers have to be very careful in making their selections. Now more than ever, the need to match the right alloy to the right application is one of the primary factors in the success of a business. Your customers want to know they are getting the cheapest, most efficient, highest quality products, and that starts with the aluminum that you use.
Among the more popular alloys, 6061 and 5052 provide manufacturers with a variety of options, thanks to their unique characteristics. While both possess the properties that make aluminum one of the most commonly used materials in the world, such as a high strength-to-weight ratio, 100% recyclability, formability, and good corrosion resistance, they also offer their own distinct attributes that allow them to specialize for particular applications. When choosing between them, it’s necessary to have a clear idea of exactly what your requirements are and a full rundown on the differences between the two.
How Are Aluminum Alloys Categorized?
Before comparing the two, now might be a good time to review the classification system for aluminum alloys. An aluminum alloy is created when other elements are combined with pure aluminum. Scientists and researchers have been experimenting with aluminum for more than a century to come up with the best performing alloys possible. These commonly added materials include iron, copper, magnesium, silicon, zinc, and manganese.
Adding these elements can improve aluminum’s core characteristics such as its strength, density, workability, conductivity, and corrosion resistance. 6061 and 5052 are both known as wrought alloys, as opposed to cast aluminum alloys (recognized because they are designated with a three digit plus decimal system xxx.x).
Wrought alloys use a four-digit designation. The first number informs us what the principal alloying element is. Each of these forms a particular series, such as the 3xxx series and the 7xxx series. The principal alloying agent in the 5xxx series is magnesium, while for the 6xxx series they are magnesium and silicon.
The second digit, if it is not 0, indicates there has been a modification to the original alloy, and the third and fourth digits are numbers that have been assigned to identify the specific alloy in the series. As an example, alloy 5182, which is used in aluminum cans, has the number 5 to start, so it is from the magnesium alloy series. The 1 indicates that it is the 1st modification to the original alloy 5082, and the 82 is used to distinguish the alloy from others in the series.
What Are These Alloys’ Specific Characteristics?
Let’s first look at 6061 alloy, which was first introduced in 1935, making it one of the first commercially available aluminum alloys. Because it’s from the 6xxx series, we know that the main elements added to it are magnesium and silicon. The magnesium boosts its strength, while the silicon helps to reduce the melting temperature. Although individually magnesium and silicon create aluminum alloys that cannot be effectively heat-treated, by combining them, the 6xxx series alloys respond well to heat treatment. The other trace elements in 6061 include chromium, iron, and copper.
6061 aluminum, recognized in the industry for its excellent structural strength and toughness, also provides for a good surface finish while offering excellent corrosion resistance. It offers good machinability, and can be easily welded and joined. After welding, 6061 may show signs of reduced strength, but it is possible to heat-treat the alloy again in order to restore strength.
As for 6061’s specific mechanical properties, its tensile strength (for 6061 T651 Bare as an example) is listed at 45,000 psi, with a yield point of 40,000 psi. The Brinell hardness is rated at 95. The elongation at break is 12% and shear strength is 31,000 psi. 6061 has a thermal conductivity of 170 W/m-K. And finally, its strength-to-weight ratio is rated at 115 kN-m/kg.
In contrast, 5xxx, treated primarily with magnesium alone, is categorized among the non heat-treatable aluminum alloys. Alloys in this series, such as 5052, feature moderate to high strength characteristics, along with good weldablility and corrosion resistance. In addition to magnesium, 5052 also has trace amounts of chromium, copper, iron, manganese, silicon, and zinc.
5052 aluminum alloy is known for its high corrosion resistance, making it suitable for applications that come into frequent contact with saltwater, wastewater, and chlorine. It is widely recognized as the best welding aluminum. In general, this alloy offers high strength-to-weight ratio, a smooth surface, and good formability because of its high modulus of elasticity. However, as previously mentioned, it is not heat treatable.
Looking at its specific mechanical properties, aluminum 5052 (H32) has a tensile strength of 33,000 psi, with a yield point of 28,000 psi. It has a listed Brinell hardness of 60. At a thickness of 1.6 mm it has an elongation at break of 12% and a modulus of elasticity of 10,200 ksi. The thermal conductivity of 5052 (H32) is 138 W/m-K.
What Are Some Of The Common Applications?
Each of these alloys is suited for specific applications. 6061 was originally used to build aircraft. Because of its tremendous versatility, this alloy can now be found in a wide range of products and industries, and is commonly used as a construction material and in the automotive industry. Manufactured articles include motorcycles, boats and bicycles, scuba tanks, camera lenses, fly-fishing reels, firearms, and electrical fittings. In the food industry, many aluminum cans are made from 6061. Docks and gangways are also constructed from this alloy.
As mentioned previously, 5052 is frequently used in welding applications. Additionally, the uses for 5052 include marine parts, aircraft, architecture, general sheet metal work, heat exchangers, fuel lines and tanks, flooring panels, street lights, appliances, and rivets and wire. Because of this alloy’s outstanding corrosion resistance versus seawater and salt spray, many large marine structures and transports employ 5052.
Summary
Regardless of the alloy you choose, aluminum offers numerous benefits, helping you to save time and money because of its dimensional stability, weldability, corrosion resistance, strength to weight ratio, and cost efficiency. At Clinton Aluminum, we take pride in helping our clients maximize their operations by finding just the right material. Our team of knowledgeable and enthusiastic sales representatives will be happy to work with you on your next project.
Resources: https://clintalum.azurewebsites.net/how-different-alloys-were-developed/
