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Tungsten Color Code Chart

The tip colors AWS A5.12 assigns to each tungsten electrode type for GTAW, with the matching ISO 6848 designations and typical uses.

Ref WG-0204AWS A5.12

Draft, open for review. Check every value against the governing standard and the manufacturer’s data before use.

What it is

Tungsten electrodes for GTAW (TIG) look alike once ground, so AWS A5.12 assigns a color painted on one end. The color identifies the oxide added to the tungsten, which changes arc starting, current capacity and suitability for AC or DC. ISO 6848 uses a similar but not identical scheme. Imported electrodes may follow ISO colors.

How to read it

Look at the painted band on the electrode end, or the color on the package.
Match it to the chart. Read the AWS classification on the box to confirm.
Grind the unpainted end. Keep the color band until the electrode is used up.

Color chart

AWS A5.12 class	Oxide addition	Tip color	ISO 6848 equivalent	Typical use
EWP	Pure tungsten	Green	WP	AC on aluminum and magnesium with older transformer machines
EWCe-2	Ceria, about 2%	Orange	WC20 (gray in ISO)	Low-amperage DC, thin material, inverter AC
EWLa-1	Lanthana, about 1%	Black	WL10	AC or DC general use
EWLa-1.5	Lanthana, about 1.5%	Gold	WL15	AC or DC; common thoriated replacement
EWLa-2	Lanthana, about 2%	Blue	WL20	AC or DC; common thoriated replacement
EWTh-1	Thoria, about 1%	Yellow	WT10	DC on steels
EWTh-2	Thoria, about 2%	Red	WT20	DC on carbon and stainless steels
EWZr-1	Zirconia	Brown	WZ8 (white in ISO)	AC on aluminum; resists contamination
EWG	Unspecified addition	Gray		Proprietary blends; maker must state the addition

Key points

Thoriated electrodes are slightly radioactive. Grind them with local exhaust and dust collection, and follow the maker's handling guidance.
Ceriated is orange under AWS but gray under ISO. Check which system the package uses before relying on color.
Proprietary "rare earth" blends are usually sold as EWG and may use colors such as purple or turquoise. Read the box.
Diameter is a separate attribute. See the measuring sheet for sizes.

Common mistakes

Assuming red always means 2% thoriated on imported stock.
Grinding off the color band and losing the identity.
Mixing loose electrodes in one tube.
Grinding thoriated tungsten on the same wheel used for other work without dust control.

Governing standards: AWS A5.12; ISO 6848.

Reference only. Verify against the current governing code or standard, the manufacturer's data and the project documents before use. Apps for Distributors disclaims liability arising from reliance on this reference.

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