Welding Gas Purity Level
The purity level of shielding gas indicates how clean the shielding gas is. A high purity level prevents porosity and embrittlement in the weld metal.
Physicochemical mechanism of action
Shielding gas purity refers to the chemical composition of shielding gases such as helium, argon, or carbon dioxide. A high level of purity means that the gas contains little dust, moisture, and other impurities.
Metallurgical relevance & risks in welding
Porosity occurs when air or other gases become trapped in the weld. Embrittlement occurs when the shielding gas is not clean enough and forms chemical compounds. Both phenomena can impair the strength and mechanical properties of the weld metal.
Workshop practice & instructions
Use shielding gas with a minimum purity level of at least 99.5%. This value ensures the gas is clean enough to prevent porosity and embrittlement. Make sure the shielding gas is properly filled and free of impurities. Monitor the purity of the gas during welding and replace it if necessary.