What is TIG welding?

TIG welding: clean seams, stable connections

Tungsten inert gas welding (TIG welding) also known as GTAW (Gas tungsten arc welding) is a gas shielded welding process and is one of the fusion welding processes. It is used wherever optimum quality and spatter-free weld seams are required. TIG welding is suitable, among other things, for stainless steels, aluminum and nickel alloys as well for thin sheet metal made of aluminum and stainless steel. It is used in pipeline and container construction, in portal construction and in aerospace applications.

TIG welding: This is how it works

In TIG welding, the required current is supplied via a tungsten electrode, which is temperature-resistant and does not melt. This electrode emits an arc that heats up and liquefies the material. There is a nozzle for shielding gas around the electrode. This protects the heated material from chemical reactions with the ambient air. The noble gases argon, helium or mixtures thereof are used for this purpose. The inert, i.e. non-reactive, gases prevent chemical reactions with the liquid weld pool and the heated material. This ensures high-quality weld seams.

As the tungsten electrode does not melt, in TIG welding the filler material is fed in by hand or in mechanized form by an external wirefeeder.

The tungsten electrode

The tungsten electrode is the heart of TIG welding. At 6116°F tungsten has the highest melting point of all pure metals in the periodic system. This means that the electrode does not melt when it emits an arc that heats and liquefies the material. The electrodes are produced using a sintering process. In order to improve their properties, they can be alloyed with oxidic additives. The electrodes are color-coded according to the alloy:

Pure tungsten (WP) (Green):

/ Smooth, spherical electrode surface
/ Ignition problems with DC
/ Low current carrying capacity

Rare earth oxide (WS2) (Turquoise):

/ can be used for all materials
/ very good ignition characteristics
/ higher durability than WT or WC-electrodes

Cerium oxide (WC 20) (Gray):

/ Can be used with all materials
/ Good ignition characteristics

Lanthanum oxide (WL 20) (Blue):

/ Longer service life than tungsten/thorium or tungsten/cerium oxide electrodes
/ Poorer ignition properties

This is how a TIG welding system is structured:

(1) Mains connection

(2) Power source

(3) Hosepack

(4) Grounding cable

(5) Welding torch

(6) Ground terminal

(7) Workpiece

(8) Filler metal

(9) Shielding gas

Advantages of TIG welding

No formation of welding spatter
Particularly high optical quality of weld seams
All welding positions are possible
Very high weld seam quality

Disadvantages of TIG welding

Requires high degree of skill
Low welding speeds
Rust must be removed without fail when preparing the weld seam
Not suitable for thick workpieces

Process variants of TIG welding

Cold wire TIG welding

A cold-wire feed increases productivity: The welding speed increases and the filler metal is fed precisely and evenly to the weld pool. This allows even less-experienced welders to achieve outstanding results.

TIG hot-wire welding

TIG hot-wire welding was developed from cold wire TIG welding. In TIG hot-wire welding, the filler metal is heated. This has various advantages: The deposition amount and rate increase, the welding speed rises and the fusion is reduced.

ArcTig

The ArcTig welding process is a TIG process variant for mechanized joint welding. It allows for an excellent weld seam appearance, reliable full penetration welding of the root pass and very high weld quality. Due to the increased welding speed and reduced work to prepare the seam, ArcTig also makes the whole welding process more cost-effective.

Cladding

Cladding is a process in which the components are coated with special alloys in order to extend their service life significantly. This coating is carried out through mechanized electro-surfacing. Fronius Speed Cladding makes the coating process up to three times faster and more efficient.

Orbital welding

The basic setup of orbital welding equipment includes a fixed pipe and a moveable TIG welding torch/welding head that moves around the pipe. The moveable orbital welding head is also referred to as a spot welding gun. The orbital welding technique is useful wherever consistent seam qualities must be attained under controlled conditions. Consequently, the main usage areas for this welding technology are pipeline construction, the food industry, and the chemical industry. With the orbital technique, it is not only possible to produce pipe-to-pipe connections, but also to weld pipes into pipe baseplates.

Which materials are suitable for TIG welding?

The most widely used materials in TIG welding include stainless steels, aluminum and nickel alloys and thin sheets of aluminum and stainless steel. With a mechanized wirefeeder, cost-effective welding speeds can be achieved for sheet thicknesses of less than 4 mm. For thicker sheets the cost-effectiveness decreases, and the TIG process is recommended for welding the root pass only. More powerful processes such as MIG/MAG or submerged arc welding are suitable for welding the filler beads.

Steel

Aluminum

Stainless steel

Professional welding systems for TIG welding

iWave 230i

Alternating current TIG welding system from the new generation
Intuitive menu navigation
Can be expanded with optional function package

Find out more about iWave 230i

Artis

Wide range of functions such as TIG pulsing
Intuitive menu navigation
Can be expanded with optional function packages

Ignis 180 TIG

Ultra-light TIG welding system
Good ignition characteristics for touchdown ignition
Can be updated for other functions

iWave 230i

Alternating current TIG welding system from the new generation
Intuitive menu navigation
Can be expanded with optional function package

Find out more about iWave 230i

Artis

Wide range of functions such as TIG pulsing
Intuitive menu navigation
Can be expanded with optional function packages

Ignis 180 TIG

Ultra-light TIG welding system
Good ignition characteristics for touchdown ignition
Can be updated for other functions

This may also interest you

What actually is … TIG welding?

What actually is … aluminum welding with alternating current (AC)?

TIG Welding: Optimum Quality Connections

ArcTig: TIG welding with speed and ease

Protective clothing for welders

Spending an entire day at the welding table is stressful. The UV radiation and the welding fumes are just some of the factors that can be dangerous if you do not have the right protection. The correct welding equipment makes the crucial difference in this area.

Send your non-binding request directly to Fronius

Let´s get connected.

Salutation

First name

Last name

Your e-mail address

Your telephone number (optional)

ZIP

City

Country

Your company (optional)

Your message to us

I have read the privacy policy and accept it.

I consent to Fronius sending me information by email and offers for other products and services for marketing purposes. This consent can be revoked at any time by sending an email to cancellation@fronius.com.

Thank you for your message. We will process your request as soon as possible.

Welding Wiki

The encyclopedia about welding

The aim of the wiki is to gather all relevant information and terms on welding in one place and share it with all those interested in welding technology.

The current page does not exist in the target language.

Perfect Welding

What is TIG welding?

TIG welding: clean seams, stable connections

TIG welding: This is how it works