Aluminum is no doubt one of the most popular metals, shaping the capabilities of our modern world. Aluminum alloys make a wide range of in-demand products possible. HVAC, smart phones, automotive parts, and marine gear all require them. Scientists, architects, and designers prefer aluminum for many reasons including high strength-to-weight ratio, flexibility, and energy savings.
After 1886—when the method for commercially producing aluminum was first introduced—aluminum has grown tremendously in popularity. This is in large part due to the needs of our modern lives and the versatility aluminum offers. Let’s use the automotive industry as a primary example.
The automotive industry is huge and revolves around the production of 95 million cars and trucks each year. At the same time, the desire for more efficient ground transportation is higher than ever. The need for lower vehicle weight, reduced emissions, and improved fuel economy has sparked intense interest in aluminum. Aluminum offers a one-two punch; it is lightweight without sacrificing strength. In fact, some aluminum alloys are as strong as structural steel.
Kloeckner Metals is a full-line aluminum supplier and service center. Download our aluminum spec sheet to see what Kloeckner Metals routinely stocks.
Aluminum’s versatility goes beyond its weight and strength. It’s easily workable into any form and can take on an impressive variety of surface finishes. Under most service conditions, aluminum shows high resistance to corrosion. Excellent machinability is one of the key factors influencing the low cost of finished aluminum parts. Almost any method of joining—riveting, welding, or brazing—applies to aluminum. Aluminum sheet can be drawn, spun and roll formed.
Aluminum is also one of the most recyclable materials. For example, in as little as 60 days, the aluminum beverage can you just finished drinking out of could be recycled and reshelved. That’s amazing!
However, much of aluminum’s versatility is owed to specific alloying elements. Pure aluminum is soft and demonstrates only moderate strength. Therefore, most applications for aluminum require aluminum alloys.
Aluminum alloys are often broken down into three categories: wrought heat treatable, wrought non-heat treatable, and casting alloys.
This group includes high purity aluminum and the wrought alloys in the 1xxx, 3xxx, and 5xxx series. Wrought non-heat treatable aluminum alloys are hardened primarily by cold working.
Heat treatable alloys have copper, magnesium, or zinc as their primary alloying element. These are the 2xxx, 6xxx and 7xxx series alloys. Wrought heat treatable aluminum alloys can be precipitation hardened. This process develops high strength levels.
This group includes both non-heat-treatable and heat treatable alloys. The most common aluminum alloys for casting are the 2xxx, 3xxx, 4xxx, 7xxx, and 8xxx. Strength properties obtained through casting are not as high for wrought heat treatable alloys.
The Aluminum Association describes how there are more than 530 registered active compositions of aluminum alloys and that number continues to grow. They’re also available in various formats including sheet, plate, tube, and bar. That’s a lot of aluminum alloys!
Given widespread applications across industries, selecting the right aluminum alloy type for a specific end-use is crucial. Just slight differences in chemical properties can drastically alter strength, workability, corrosion resistance, and electrical conductivity of the alloy.
With a purity of 99.0% or greater, 1100 is often called commercially pure aluminum. It is the softest of the common alloys.
3003 aluminum is the best known and most widely used of the common alloys. 3003 aluminum is non-heat treatable. With about 20% more strength than 1100, 3003 is a practical general-purpose aluminum for moderate strength applications.
3004 aluminum is very similar to 3003 aluminum in its composition and end-uses. However, 3004 shows more strength due to a 1% addition of magnesium.
Though 3105 is non-heat treatable, it can be annealed during cold working.
5052 is the strongest non-heat treatable sheet and plate in common use. Versatility and strong value make it one of the most serviceable alloys.
6061 is one of the strongest aluminum alloys. It is considered the least expensive and most versatile of the heat treatable alloys. Though less formable, it is commonly extruded.
6063 aluminum is mainly an extrusion alloy used almost exclusively by the architectural applicators. It is heat treatable for strengthening.
Kloeckner Metals supplies aluminum nationwide from 15 branches in the United States and Mexico. Please visit our branch directory and use our filter tool to see which branches supply the type and grade of aluminum you require for your business needs.
Kloeckner Metals is a full-line aluminum supplier and service center. Kloeckner Metals joins a national footprint with the latest fabrication and processing technologies and innovative customer service solutions.
Aluminum comes in many different shapes and grades. The type of aluminum grade you choose ultimately depends on how you intend to use the metal. Your intended use allows you to rank the characteristics of each grade from most important to least important. This will help you narrow down the list of suitable grades. For example, if weldability is most important to your project, but strength is not, it may make sense to choose Alloy 1100, as this aluminum grade has excellent Weldability, but is not typically used for high-strength or high-pressure applications.
Use the quick reference chart at the end of this article to quickly and easily find the aluminum grade that is right for you.
Quick Reference Chart – Choosing an Aluminum Grade
Formability or Workability Weldability Machining Corrosion Resistance Heat Treating Strength Typical Applications Alloy 1100 Excellent Excellent Good Excellent No Low Metal Spinning Alloy 2011 Good Poor Excellent Poor Yes High General Machining Alloy 2024 Good Poor Fair Poor Yes High Aerospace Application Alloy 3003 Excellent Excellent Good Good No Medium Chemical Equipment Alloy 5052 Good Good Fair Excellent No Medium Marine Applications Alloy 6061 Good Good Good Excellent Yes Medium Structural Applications Alloy 6063 Good Good Fair Good Yes Medium Architectural Applications Alloy 7075 Poor Poor Fair Average Yes High Aerospace Applications
Disclaimer: Please note this information is not to be used for design purposes, and in no event shall MSFFC be liable for any damages arising from the misuse of this information.