Aluminum is rightly celebrated for its amazing diversity and formability. In fact, it’s hard to think about an industry that hasn’t been profoundly changed by the introduction of aluminum in the past 100 years. Nearly every part of our daily lives, from the food we eat to the vehicles we drive to the devices we use, likely has been made with or packaged in aluminum.
But it’s also important to note that aluminum is not always the easiest material to form. Most critically, every alloy reacts differently to industrial processes. Even a single alloy can be tempered in various ways depending on what type of heat treatment it undergoes. With this in mind, a manufacturer must pay close attention to what alloy it chooses for any particular application.
Today we’re going to look at the various ways that aluminum can be formed and what challenges must be overcome. While this will just be an overview, it’s essential that you carefully look at all the requirements of your application before selecting a specific alloy for the job.
What are the different types of forming techniques?
Aluminum really is an amazing material. Since it’s development early in the 20th century, it has impacted nearly every industry thanks to its many beneficial attributes. Not only is it extremely light weight with a tremendous strength-to-weight ratio, but it’s also corrosion resistant and cosmetically appealing. Other benefits include the fact it’s easily recyclable and offers many possibilities for manufacturers and designers who often have very specific shape requirements.
That’s where formability comes in. Thanks to aluminum’s versatility, there are a number of different options when it comes to shaping an aluminum alloy in order to ensure that it meets your required specifications. Forming processes employ some form of stress, including compression and tension, in order to deform the material into the required shape without damaging it. No actual material is removed.
One of the most popular forming techniques is known as rolling. This is when the aluminum stock is passed through heavy rollers in order to flatten the metal to a uniform thickness. Rolling is categorized as compressive forming. Roll forming is a similar process whereupon a series of consecutive roll stands incrementally bend a workpiece, normally coiled strip product, into a desired cross section. Other examples include extrusion, where heated aluminum billet is forced through a specifically shaped die, forging, and indenting.
Tensile forming is another broad category of forming. This includes stretching, in which a load is applied along the longitudinal axis, expanding, which means the size of a hollow body is increased due to tangential loading, and recessing, in which depressions are created through tensile loading.
Also common is bending, a process that involves creating a V-, U-, or channel-shape along a straight axis. This is most commonly used with sheet metal. Other forming options include drawing, spinning and indenting.
What are the challenges of forming aluminum?
While there are many options open to you when it comes to forming aluminum, the truth is that there are certain challenges working with this metal. First of all, compared to some other popular metals, such as steel, aluminum tends to lack elasticity. This means that you must be careful using forming techniques in order to avoid wrinkling.
Also, when you aren’t using a lubricant in between the workpiece and the forming tool, it can lead to harsh mechanical interaction between the two. This kind of interaction can result in adhesive wear on the aluminum. Not only can this adversely affect the surface quality of the aluminum, but it can also wear down the tool or render it unusable.
No matter what your specific requirements, it pays to do your homework beforehand. Whether it’s taking the time to prototype your application or ensuring that you pick just the right alloy, it’s possible to overcome the challenges posed by forming aluminum.
Which alloys respond best to forming?
As is commonly understood, aluminum alloys can be divided into different families, based on the 4-digit number used to identify it. Broadly speaking, each series responds to forming differently. For example, the 1xxx series of alloys normally offer excellent formability, whereas the 2xxx series, while easily machined, are not very formable.
The 3xxx, 4xxx, and 5xxx series are all appreciated as being relatively formable. The 7xxx series, like the 2xxx series, is known for being easily machined but isn’t as appropriate for forming applications. Finally, the 8xxx series of aluminums is generally regarded as having excellent formability and is a good choice for applications that require it.
Some specific alloys of note include alloy 3003, 5052, 5083, and 6061; all famous for their formability.
Of course, as mentioned in the introduction, the alloy alone is not the only factor in determining aluminum’s formability. The temper is also important. As a rule of thumb, when dealing with non-heat treatable alloys, additional strength can be gained through work hardening. It’s then possible to achieve the desired properties in the annealing stage. On the other hand, with alloys that are heat treatable, it’s possible to increase the strength by heating the metal followed by quenching.
What applications rely on aluminum forming?
No matter what your application, it’s possible that some kind of forming technique will be involved, even if it occurs before you procure the aluminum. For instance, if you are using sheet, plate or extrusions, it will have been formed prior to your purchase.
Your Trusted Services Provider
For manufacturers, the various options for forming aluminum offer a tremendous amount of versatility that lends itself to numerous industries. No matter which industry you are working in, selecting the right material and making sure it meets your quality standards is of paramount importance. Working with a trusted supplier with the experience and knowledge to understand your needs can make all the difference.
At Clinton Aluminum, our team of technical professionals takes pride in having the ability to quickly fill your orders, in the most accurate and convenient manner possible. We strive to work closely with our customers to make sure they get the right material matched to their specifications every time. Just as importantly, we work with them along every step of their selection process.
For more information about how we can help you with your aluminum supply needs, contact one of our friendly and knowledgeable representatives today.