TIG and MIG welding are two popular types of welding that use different types of welding wires.
This article will explain the meaning of TIG and MIG welding wires and how they differ from each other in terms of their properties, advantages, and disadvantages.
AWS Classification System
The AWS (American Welding Society) has established a classification system for welding consumables, including filler metals used in TIG (Tungsten Inert Gas) and MIG (Metal Inert Gas) welding processes.
This system includes various standards for different types of filler wires, depending on their composition and intended use.
For instance, AWS A5.18 is the standard that specifies the classification requirements for carbon steel wires used in TIG and MIG welding.
This standard outlines the chemical composition, mechanical properties, and other essential characteristics that carbon steel filler wires must meet to ensure their suitability for welding applications.
In contrast, AWS A5.28 covers low alloy steel solid filler wires used in TIG-MIG welding.
These filler wires are specifically designed to join low alloy steels and provide excellent mechanical properties, including high tensile strength, impact toughness, and other characteristics such as PWHT conditions.
Example classification system for ER70S-6 means:
- The “ER” designation indicates it is an electrode or rod/wire used in GMAW and GTAW processes.
- The number 70 represents the minimum tensile strength of 70 ksi.
- The “S” indicates it is a solid wire.
- The “-6” designation denotes a specific wire composition that typically includes carbon, manganese, silicon, and small amounts of other elements.
CSA W48-01 Classification System
CSA Standard W48-01 outlines the requirements for filler metals utilized in carbon steels, while AWS Specification A5.28 covers those used in higher-strength steels that have an ultimate tensile strength greater than 490 MPa.
Gas metal arc welding wires are categorized according to their composition and the anticipated strength of the weld metal.
An example of a gas metal arc welding electrode specification typically includes information about its tensile strength and composition as:
- ER XX S-XXX
Where,
- E means Electrode,
- R means rod or wire for TIG and MIG welding,
- XX means the minimum specified tensile strength in Ksi for the wire,
- S means Solid wire.
- XX, The composition of the wire can be recognized by a combination of one to three digits or an alphabet-digit combination represented by xxx.
If you come across a wire with the designation ER49S-2, you can expect that the deposited weld will have a minimum tensile strength of 490 MPa.
The wire contains nominal amounts of zirconium, titanium, and aluminum, which helps with deoxidation, in addition to silicon and manganese.
These wires are ideal for producing quality welds in semi-killed and rimmed steels, particularly when using the short-circuiting method of metal transfer.
Even when there is some rust present on the steel surface, these wires can still produce acceptable welds.
Overall, ER49S-2 wires are a reliable option for welding and can produce sound welds even in less-than-ideal conditions.
Most Commonly used TIG & MIG Welding Wires
Here are the most commonly used TIG and MIG welding wires for carbon steel and low alloy steel welding:
TIG Welding Wires:
- ER70S-2: This wire is commonly used for welding carbon and low alloy steels, providing good weld penetration and ductility.
- ER80S-D2: This wire is designed for welding high-strength low-alloy (HSLA) steels and can produce strong and crack-resistant welds.
- ER70S-6: This wire is also used for welding carbon and low alloy steels and provides good penetration and spatter control.
- ER80S-G: This wire is designed for welding high-strength low-alloy (HSLA) steels, providing good strength and impact toughness.
- ER80S-B2: This wire is designed for welding low alloy steels, specifically those containing 0.5% molybdenum, providing good strength and corrosion resistance.
MIG Welding Wires:
- ER70S-2: This wire is commonly used for welding carbon and low alloy steels, providing good weld penetration and ductility.
- ER70S-6: This is the most commonly used MIG wire for welding carbon and low alloy steels, providing a good weld appearance and low spatter.
- ER80S-D2: This wire is also commonly used for welding HSLA steels, producing strong and ductile welds.
