Aluminum is celebrated by manufacturers in almost every industry for its versatility. In fact, because of the tremendous diversity of aluminum alloys, aluminum is the solution of choice for a wide range of applications. However, its adaptability and variety also mean that it can be difficult to know which alloy is the right one for any given task. That’s why it is critical that manufacturers do their homework prior to production to make sure that they choose the best possible alloy for the job at hand.
Alloys 6061 and 2024 are among the most popular for many different industries. And while they both exhibit many of the characteristics that have made aluminum such a sought-after material for the past century, offering light weight, high strength, and good corrosion resistance, they each have their own unique properties.
How Are Aluminum Alloys Classified?
For those new to the industry, the various alloy classifications of aluminum can be quite confusing. Alloys are formed by combining pure aluminum with other elements, known as alloying agents, to improve the material’s strength, density, workability, conductivity, and more. These agents can include iron, copper, magnesium, silicon, zinc, and manganese.
Alloys such as 6061 and 2024, with four-digit designations, are known as wrought alloys, and are distinguished from cast aluminum alloys, which use three digits plus a decimal in their name. In the four-digit system, the first number indicates the principal alloying agent. For the 2xxx series, including 2024, the principal element that is added to the aluminum is copper. For the 6xxx series, both magnesium and silicon are added.
As for the rest of the numbers, the second digit, assuming it is not 0, tells us that there has been a modification to the original alloy, while the third and fourth digits identify the specific alloy in the series (as a naming mechanism). For example, alloy 5182, commonly found in aluminum cans, has the number 5 to start, so it is from the magnesium alloy series. The 1 means that it is the first modification to the original 5082 alloy, and the 82 distinguishes the alloy from others in the series.
A Comparison Of 2xxx series And 6xxx Series Aluminum
The 2xxx series aluminum alloys are heat treatable, high strength, and high performance metals that, as previously mentioned, use copper as their principal alloying agent. Because of their excellent strength over a wide range of temperatures, they are often employed in aerospace and aircraft applications. They have excellent strength over a wide range of temperatures. They are commonly vulnerable to heat cracking and stress corrosion when welded, so they must be welded with very specific procedures, and for some of the alloys in this series, arc welding is not an option.
The 6xxx series alloys are also heat treatable and use magnesium and silicon as their main alloying agents. The alloying process for these alloys allows for the metal to be solution heat treated, and is a major reason why they are so popular in welding fabrication, extrusions, and various structural components. They are susceptible to cracking and are therefore not well suited to arc welding unless enough filler material is employed.
What Are The Specific Properties Of 2024 And 6061 Aluminum?
When choosing between two particular alloys, it is important to fully compare their unique properties. 2024 is among the more popular high strength aluminum alloys. It is recognized for its strength and fatigue resistance and offers a good strength-to-weight ratio.
As for its specific attributes, 2024-T3 aluminum has a Brinnel hardness of 120, with an elastic modulus of 71 GPa. Its elongation at break is 15% and its tensile strength is rated at 480 GPa. Its thermal conductivity is rated at 120 W/m-K, with a thermal expansion of 23 µm/m-K.
By comparison, 6061 (T651 Bare) has a tensile strength 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 thermal expansion is 24 µm/m-K.
What Common Applications Feature 2024 Or 6061 Aluminum?
Both of these alloys are popular choices for a wide range of products and applications. 2024 is commonly extruded, and comes in both sheet and plate form. As a result of its high strength and fatigue resistance, it is employed in aircraft structures, especially the wings and fuselage, which are frequently under tension. Many parts for the transportation industry use this alloy. 2024 also is found in many large hydraulic manifolds.
Thanks to its versatility, 6061 aluminum is widely employed in many different industries. Most prominently, 6061 is a favorite construction material and frequently used in the automotive industry. Other typical uses include in motorcycles, boats, bicycles, scuba tanks, camera lenses, fly fishing reels, firearms, and electrical fittings. In the food and beverage industry, aluminum cans are often made of 6061 aluminum. Many docks and gangways are constructed from this alloy. This is of course in addition to the plethora of aircraft parts that still use 6061.
How To Choose The Aluminum That’s Right For Your Application
Manufacturers should always have a checklist of considerations when choosing what alloy to use. You have the best understanding of what the requirements are for your production job, and you’ll want to keep your priorities in mind as you compare various materials. Important questions include:
- Does your application require a high degree of formability?
- Will welding be a part of the production process?
- Is machining an important factor?
- Will your product be exposed to the elements (in particular, seawater or other highly corrosive environments)?
- Will your application require heat treatment?
- How important is the strength-to-weight ratio?
Summary
No matter how you answer the above questions, there’s most likely an aluminum alloy that will check all the boxes. At Clinton Aluminum, we do our utmost to be a technical resource partner to our customers. We will work with you to make sure you find the right material for your production needs.
