All About TIG Welding

What Is TIG Welding?

Tungsten inert gas (TIG) welding (also known as gas tungsten arc welding (GTAW)) is a precise process used to create high-quality welds. The term "TIG" (tungsten inert gas) references the non-reactive gas (usually argon) employed to protect the weld area from atmospheric contamination. It joins metals using a non-consumable tungsten electrode while protecting the welding area from atmospheric contamination with an inert gas such as argon. The exceptional control and versatility of TIG welding, which can join a variety of metals including copper, aluminum, and stainless steel, are its main selling points.

TIG welding has many advantages, including excellent weld quality, exact control over heat input, minimal spatter, and the ability to create welds that are pleasing to the eye. This article will examine the fundamentals of TIG welding, including how it functions, practical application tips, and its numerous advantages. Let's dive in and learn about TIG welding.

How TIG Welding Works

As mentioned above, TIG welding joins metal parts using a tungsten electrode. An inert gas (usually argon) shields the electrode and the workpiece to prevent oxidation. The electrode and workpiece produce a high-temperature arc that melts the metal, forming a weld pool. The manually introduced filler material can reinforce the joint.

To apply TIG welding effectively, follow these steps:

1. Gather the necessary equipment: TIG welding machine, tungsten electrode, filler rod, gas cylinder, protective clothing, and welding helmet.
2. Prepare the workpiece by cleaning it thoroughly with a wire brush or solvent to ensure a clean surface.
3. Set up the TIG welding machine and adjust the settings to match the material and thickness.
4. Grip the TIG torch with your hand, positioning it at an angle of around 70 or 80 degrees. Lift the torch slightly, keeping the tungsten tip 1/16 to 1/8 inch from the workpiece. Be careful not to let the tungsten come into contact with the workpiece as this can lead to contamination of the material, requiring you to regrind the tungsten.
5. Maintain a steady hand and move the torch in a controlled manner, directing the arc along your desired weld path.
6. Control the heat input by adjusting the amperage and filler rod as needed.
7. Keep the torch close to the workpiece for better control and visibility.
8. Once the weld is complete, gradually reduce the amperage and allow the weld to cool.
9. Inspect the weld for defects and make adjustments or repairs as necessary.

Parts of a TIG Welding System

A TIG welding system is composed of: 

1. Power Source: Provides electrical energy for the welding process.
2. TIG Torch: Holds the tungsten electrode and controls the shielding gas flow.
3. Tungsten Electrode: Forms the arc and withstands high temperatures.
4. Shielding Gas: Protects the weld area from atmospheric contamination.
5. Filler Metal: Optional material added to reinforce the weld.
6. Gas Cylinder: Stores the shielding gas, such as argon or helium.
7. Foot Pedal or Hand Control: Regulates the welding current.

Materials That Can be TIG Welded: A Wide Range

TIG welding functions on a variety of materials, including:

1. Aluminum

Oftentimes, TIG welding is the optimal choice for aluminum parts. Welded aluminum is used for applications in aerospace, automotive, and other industries.

2. Stainless Steel

When TIG welding stainless steel, employ a DC machine to give the electrode negative polarity. The TIG torch must be connected to the negative terminal of the welder and the ground clamp to the positive terminal. Doing so gives you better control over heat input, minimizes distortion, and ensures the integrity of the stainless steel's corrosion-resistant properties.

3. Steel

TIG welding is suitable for many types of steel, including carbon steel and low-alloy steel. It allows for precise control over heat input and produces high-quality welds with minimal spatter. TIG welding is commonly used in structural fabrication, piping, and automotive production. For more information, see our guide on Steel Metals.

4. Chromoly

Chromoly (chromium-molybdenum alloy) is a popular material in motorsports and bicycle manufacturing. TIG welding produces strong, crack-free welds that other processes can’t match on chromoly materials.

5. Nickel Alloys

Nickel alloys, which are renowned for their corrosion resistance and high-temperature strength, are usually welded using TIG machines. Nickel alloys typically need shielding gasses like argon, helium, or a mix of the two for the best results. An alternative is to use an argon-hydrogen gas mixture designed specifically for welding pure nickel. It is appropriate for use in the power generation, chemical processing, and aerospace industries.

How TIG Welding is Used in Key Industries

Examples of TIG (tungsten inert gas) welding applications include:

1. Automotive Industry: TIG welding is used to assemble exhaust systems, fuel tanks, and engine components.
2. Aerospace Industry: It is employed on aircraft components like engine parts, aluminum and titanium structural members, and fuel lines.
3. Fabrication Industry: For various fabrication projects, TIG welding is used to join non-ferrous metals like aluminum, copper, and others.

Advantages and Disadvantages of TIG Welding

Advantages of TIG welding include:

1. Precise, clean, and aesthetically appealing welds.
2. It can be used to weld a wide range of metals, including stainless steel, aluminum, copper, and nickel alloys.
3. Thin materials can be TIG welded thanks to precise heat control.
4. Less post-weld cleanup is required because TIG welding produces little spatter.
5. Strong and reliable welds with good fusion are produced by TIG welding.

Disadvantages of TIG welding include:

1. Compared to other welding techniques like MIG, TIG welding generally takes longer.
2. TIG welding requires a higher level of skill and expertise to operate the equipment effectively.
3. It may be challenging to weld thick materials because of the TIG process’ slow deposition rate. 
4. In comparison to MIG welding and oxyfuel welding, TIG welding supplies and equipment can be more expensive.

Differences Between TIG Welding and Laser Welding

The main differences between TIG welding and laser welding are:

1. Heat Source: TIG welding heats the workpiece using an electric arc between a tungsten electrode and the workpiece, while laser welding employs a high-powered laser beam.
2. Speed: Laser welding is typically faster than TIG welding.
3. Precision: With a smaller heat-affected zone and greater precision, laser welding produces more compact welds.
4. Material compatibility: While TIG welding only works with metals, laser welding is appropriate for a variety of materials, including metals and certain plastics.

Xometry provides a wide range of manufacturing capabilities, including sheet cutting, CNC machining, and 3D printing for all of your prototyping and production needs. Get your instant quote in seconds today.

Disclaimer

The content appearing on this webpage is for informational purposes only. Xometry makes no representation or warranty of any kind, be it expressed or implied, as to the accuracy, completeness, or validity of the information. Any performance parameters, geometric tolerances, specific design features, quality and types of materials, or processes should not be inferred to represent what will be delivered by third-party suppliers or manufacturers through Xometry’s network. Buyers seeking quotes for parts are responsible for defining the specific requirements for those parts. Please refer to our terms and conditions for more information.