← Glossary

Forming gas nitrogen-hydrogen

A reducing auxiliary gas mixture used for root protection during welding of austenitic steels to prevent oxidation on the reverse side of the weld.

Forming gas with nitrogen-hydrogen is used on the back side of the weld to protect the weld zone from oxygen. The hydrogen in the mixture prevents oxidation at the root and ensures a clean, pore-free weld. Without this protection, the back side burns and the weld becomes brittle. You have to feed the gas so that it covers the entire root, then you'll have a clean and durable weld.

MetallurgieSchweißtechnik

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