The use of aluminum in manufacturing industries is on the rise because of its many properties. Aluminum is lightweight, strong, corrosion-resistant, and easy to fabricate. Welding is one of the final steps in aluminum metal manufacturing. Compared to riveting, welds are permanent and do not add to the overall weight of the components. One of the most suitable devices you can use to join aluminum parts together is a TIG welder. TIG welders produce clean welds and can work with thin aluminum components. This device is fast and increases productivity.
Are you a novice or seasoned welder and want to know how to weld aluminum with a TIG welder? Then, you are in the right place. This article will be your guide on everything TIG welding aluminum. It will explain what an aluminum TIG welder is, the step-by-step process of TIG welding aluminum, and factors to consider for the best welding experience.
What is a TIG Welder
A TIG welder is a device you can use to join two or more metal parts together. It is made up of a welding torch, power source, electrode holder, and foot pedal or control as the major components. A TIG welder works by forming an electric arc between the workpiece and the electrode.
The arc generates heat that melts the base metal leading to a weld pool. The base metal fuses together as they cool and solidify. You should note that the tungsten electrode here is non-consumable. It does not melt during the welding process. Hence, you don’t have to frequently replace it.
Can You Tig Weld Aluminum
Yes, it is possible to weld aluminum metal using a TIG welder. TIG welding is one of the most common techniques to join aluminum parts together. You can also use it to fuse aluminum and other metals such as stainless steel with ease. The reasons for this are not far-fetched. Aluminum has a low melting point and dissipates heat rapidly which makes it easy for you to weld. It does not require high heat input to get quality and durable welds.
Furthermore, this metal has low reactivity and high electrical conductivity. Hence, it is more straightforward to establish and maintain a stable arc. This makes it possible to weld at a fast rate without the risk of porosity and other defects.
How to Tig Weld Aluminum
The process of using a TIG welder to join aluminum parts require basic knowledge and skills. This tool is simple to use and handle. For a seamless welding process, follow the steps below when operating a TIG welder.
Preparation
The first step is to prepare the workpiece and the welding environment. To prepare the aluminum workpiece, you have to clean off all dirt and contaminants that can interfere with electrical conductivity. You do this using a neutral cleanser dissolved in an appropriate quantity of water.
When cleaning the workpiece, gently apply the soap mixture using a clean cloth. You then rinse off and dry. Furthermore, prepare the environment and yourself by ensuring good ventilation and wearing the required PPEs.
Set-Up
Now it’s time to set up and configure the TIG welder. Assemble all parts according to the manufacturer’s instructions. Choose and install the tungsten electrode. For aluminum, you may want to go for a pure tungsten rod or a 2% thoriated tungsten electrode to get the best result.
After choosing the electrode, grind it to make the tip sharp and rounded. The next step after getting the desired shape and angle is to insert the electrode in a collet. The collet positions and holds the electrode in place for a smooth welding experience.
Welding Process
Before welding, adjust the parameters based on the workpiece thickness in question. Hold the TIG torch at an appropriate angle from the workpiece. Move the torch steadily at a constant speed to establish the arc. Adjust the current and add filler material if needed. A weld pool is created that joins the parts together.
Slowly reduce the amperage and allow the weld pool to solidify. When working with a TIG welder to fuse aluminum metal, it is important to use pure argon as the shielding gas. Argon is non-toxic and protects the weld pool from atmospheric contamination.
Inspection and Finishing
The final step in using a TIG welder is to inspect and confirm how well it has performed. Check for both the internal and external welding defects. You can visually inspect external defects such as cracks and undercuts. For internal ones, you may have to use techniques such as magnetic particle, ultrasonic, and radiographic inspection. If the final weld is of high quality and meets specified requirements, then you are good to go. In certain instances, you may have to reweld or grind to remove the defects.
Factors to Consider When TIG Welding Aluminum
To make the most of your TIG welder, there are some factors you should consider. The following are important TIG welding tips you should follow to get the best results.
Choose the Right TIG Welder
There are different types of TIG welders available. They differ based on their size, type of current, power, and cooling system. Make sure you go for a TIG welder with the required power output and cooling system. It should also be compatible with the particular aluminum alloy to ensure optimal results.
Proper Electrode Preparation
You must prepare the electrode before every use when working with a TIG welder. It involves grinding it to ensure a stable arc. A well-prepared tungsten electrode ensures that the final weld is of a high quality. Furthermore, proper preparation extends the life of the tungsten electrode and improves weld penetration.
Proper Positioning
The way you position the TIG torch makes all the difference. The torch should be held between 10 to 20 degrees vertically in the weld’s direction. This position gives you precise control and makes it easy to add filler materials. Furthermore, the tungsten electrode should be about 6mm away from the aluminum workpiece. The electrode must not touch the part to avoid contamination.
Control Heat Input
You should avoid using too much heat just to speed up the welding process. Aluminum has a low melting point when compared to most engineering metals. Hence, it can easily melt away when welding. You should start from the lowest amperage and gradually increase it till you get the desired results.
Use the Right Filler Material
The filler material you use will determine the success of the TIG welding operation. The material must closely resemble the aluminum alloy in terms of composition and properties. Furthermore, consider the size of the filler material. Too big a material will cause the final weld to bulge out and may not be aesthetically pleasing.
Preheat the Workpiece
Consider preheating the aluminum workpiece especially when working with sections that are 1 inch thick or more. This slight rise in temperature helps to prevent thermal shock which can cause cracking or distortions. Additionally, preheating ensures optimal penetration and minimizes the occurrence of incomplete welding.
Cleanliness is Key
The initial state of the aluminum workpiece determines the result. You must clean off all dirt and dust that can interfere with the TIG welding process. Contaminants can react and cause pores that will weaken the final weld. Furthermore, they can serve as a barrier between the filler material and base metal leading to incomplete fusion.
What Industries TIG Weld Aluminium
Many part manufacturers across industries use TIG welders for sheet metal fabrication. This device is fast and produces strong and crack-free welds. The following are the most common industries that use TIG welding to fabricate aluminum components.
Automotive Industry
The automotive industry uses TIG welders extensively for both manufacturing and repair works. They are useful when welding various components such as body panels, exhaust systems, frames, and chassis. TIG welders improve the performance of a car and ensure passenger safety. They don’t burn through and enhance aesthetics.
Aerospace Industry
TIG welders are suitable options for joining many aerospace aluminum alloys. The final welds are accurate and meet industry specifications. From engine parts and fuel tanks to structural elements, TIG welders are useful. The final welds are impeccable, robust, and durable.
Medical Industry
You can also use a TIG welder in the fabrication of medical devices and machines. The welds are clean and do not compromise the safety of patients. TIG welders are indispensable when manufacturing surgical instruments, medical implants, and prosthetics. You would also find them useful when assembling heavy diagnostic machines and pharmaceutical equipment.
Packaging Industry
TIG welders can weld thin aluminum sheets used in the packaging industry. This tool gives you greater control over the process making it easy to fabricate cans and bottling lines in beverage packaging. TIG welders have a low heat input and are suitable for manufacturing packaging machines.
Art and Craft
TIG welders play a huge role in metal art and design. The welds confer stability and can meet most design requirements. The final welds are strong, durable, and do not break down even when you displace the art pieces in public for an extended period. You can use TIG welders to combine different metals and shapes.
Conclusion
It can be challenging to weld aluminum because of its low melting point and high thermal conductivity. However, using a TIG welder helps to overcome these limitations because you can control the amount of heat input and prevent overheating and burn-through. The process of aluminum TIG welding is easy for both novices and professionals. It involves preparing the workpiece and environment by ensuring proper ventilation. You then weld at a constant speed while controlling the heat input. However, you must properly position the tungsten electrode and use the right filler material to get a high-quality weld.
