Aluminum is indispensable in the manufacturing realm because of its lightweight, versatility, and cost-effectiveness. There are different techniques you can use to turn aluminum stock into functional products, and sheet metal fabricating is just one of them. This process involves cutting, bending, and joining aluminum metal sheets to produce useful parts and components. Aluminum metal sheet fabrication is eco-friendly, and accurate and allows for rapid prototyping and production.
There are many ways to fabricate aluminum metal sheets. The one you use depends on what you are trying to achieve and your project requirements. This article will explain the process of aluminum sheet fabrication, how it works, and some common aluminum metal grades you can use.
What is Aluminum Sheet Metal Fabrication?
Aluminum sheet metal fabrication is the process of converting aluminum sheets into various shapes and sizes. It may involve mechanical deformation or the addition and removal of materials. The end products are useful 2D or 3D objects that are lightweight and strong.
How does Aluminum Sheet Metal Fabrication Work?
Aluminum sheet metal fabrication is a combination of various techniques and processes. Let’s explain how it works using the three steps below
Preparation
- The first stage is to select the most appropriate grade of aluminum sheet.
- Thereafter, you clean off dirt and debris using a water or alkaline-based cleanser.
- You then sketch the design you want to replicate. You can do this manually or with the aid of Computer-aided design (CAD) software.
Fabrication
- The next step is to fabricate the aluminum sheet to get the desired design and shape.
- You do this by cutting, forming, or joining. Most times, you may have to use more than a single technique to obtain the desired result.
Finishing
- After getting your fabricated aluminum parts, the next step is to carry out various post-processing operations as needed.
Note: Aluminum is compatible with many finishing options including anodizing, powder coating, and bead blasting.
Key Processes in Aluminum Sheet Metal Fabrication
‘Process of using a plasma cutter to produce intricate designs on a sheet of aluminum’
There are many ways to fabricate aluminum sheets. These techniques have different advantages and unique objectives. It is important to understand each one and determine its suitability before using any. The most common processes in aluminum sheet metal fabrication include
- Cutting
Cutting involves the removal of material from the aluminum sheet. Most cutting techniques involve a shear force while others may not.
Cutting with shearing
Shearing involves placing the aluminum sheet in between two blades. As the metal stock comes in contact with the blades, it is split in a straight line into smaller pieces. Note that for this to occur, the force must be greater than the shear strength of the aluminum sheet. Shearing is easy to carry out and less expensive. However, it comes with limited accuracy and may not be suitable for applications with tight tolerances.
Cutting without shearing
There are other cutting approaches that do not involve blades and a shear force. You can carry out this process using laser cutting, plasma cutting, or waterjet cutting systems.
- Bending
Bending is a deformation process that involves the application of force to alter the shape of a sheet of aluminum. It uses a press brake tool to exert pressure to produce new angles usually U or V shaped. Bending enhances productivity and is ideal for very thin sheets. Additionally, it is a fast process as a bend takes just a few seconds.
- Curling
Curling is a forming operation that creates a curved edge out of an aluminum sheet. The final part has a hollow ring that eliminates sharp edges and makes it safer to handle. Note that it is important to carry out the curling process gradually. You first pre-bend before using a curling die to progressively shape the workpiece.
- Hemming
Hemming is similar to curling but they are not the same. In hemming, you fold the aluminum sheet over itself to increase the edge strength. This flat folded edge is mostly used for structural reinforcement. There are two main types of hem; open and closed hem. An opened hem allows for a bit of space in the hem while a closed hem doesn’t.
- Stamping
Stamping uses a die and specialized tooling to shape a blank aluminum sheet. To carry out stamping, the first step is to design a die based on what you want the final part to look like. Place the sheet in between the die halves and close. Apply force and pressure to deform the metal sheet and shape it based on the die’s contours.
- Welding
Welding utilizes heat and pressure to join two or more aluminum sheets together. In certain instances, it is necessary to add a filler material to create a stronger joint. There are different welding methods available with MIG and TIG welding being the most common. Welding creates a permanent joint that is not reversible.
- Fastening
Fastening is a more cost-effective joining process when compared to welding. It involves the use of fasteners such as rivets, bolts, and screws to hold aluminum parts together. Fastening is easy to carry out and does not require skilled labor. However, it adds to the overall weight of the component and drilled holes may affect the structural integrity of the part.
Types of Aluminum Used in Sheet Metal Fabrication
There are many grades of aluminum metal available. However, not all are suitable for sheet metal fabrication. The following are the most common types used
- 5052
It is an alloy that contains a high content of magnesium, usually 2.5% and 0.25% chromium. It is corrosion-resistant with moderate strength and you can easily work on it. 5052 is a perfect candidate for rapid prototyping and small-batch production. However, experts advise against heat treating this alloy to increase its hardness and strength.
- 6061
The 6061 aluminum alloy is also known as ‘alloy 61S’. It is composed of 0.9% magnesium, 0.7% silicon, and 0.6% iron as the major alloying elements. It has excellent formability and weldability properties. Furthermore, it is ductile and you can carry out various heat treatment methods for a higher strength level. It is ideal when manufacturing automotive parts and building facades.
- 7075
A common name for this aluminum alloy is ‘aircraft grade’. It is stronger than the types previously described. 7075 aluminum alloy contains zinc as the primary alloying element with traces of magnesium, copper, and silicon. It has moderate formability and exhibits good resistance to fatigue. This aluminum alloy grade should be your go-to when constructing aircraft structures.
- 3003
The 3003 aluminum alloy is a general-purpose alloy that has manganese as the major alloying element. The high manganese content reinforces its hardness and toughness. It is suitable for outdoor applications because of its excellent resistance to atmospheric corrosion. You would find it in storage tanks, chemical equipment, and corrugated roofing.
What Industries Use Fabricated Aluminum Sheet Parts?
Many industries use aluminum for sheet metal fabrication. It is the most abundant metal on earth and weighs one-third of steel. Common industries that use fabricated aluminum sheet components include
Medical Industry
Medical parts manufacturers use fabricated aluminum sheets extensively. It is useful when making diagnostic, dental, and surgical devices. This technique offers a short lead time and produces flexible and durable components. Furthermore, aluminum is corrosion-resistant and the parts do not degrade when in contact with bodily fluids.
Aerospace and Aviation
Fabricated aluminum parts provide an excellent strength-to-weight ratio. This property is key in the aerospace and aviation industry. The lighter the part, the lesser the fuel consumption. You will find it in many structural applications such as fuselages and wings.
Energy Sector
Aluminum sheets also play a role in the energy industry. It is affordable and most grades have a low carbon content. Fabricated aluminum is useful when building solar panels, electric vehicles, and wind turbines.
Military and Defense
Fabricated aluminum sheets are an important part of the military and defense sector. The final products are lightweight, can be easily handled, and absorb impact. It has applications when manufacturing guns, mines, and military vehicles.
Conclusion
Aluminum sheet metal fabrication involves manipulating aluminum sheets to produce sturdy and functional components. There are many ways to go about this and the technique you use depends on what you want to achieve. This guide has discussed aluminum sheet fabrication in-depth, the most suitable materials you can use, and their applications in manufacturing industries.