Flux
Fluxes are chemical substances that remove oxides and protect the molten metal from oxidation. They improve wetting and promote the fluidity of the weld pool.
Physicochemical Mechanism of Action
Fluxes react with oxides in the molten metal to dissolve and break them down. They protect the metal from re-oxidation by oxygen and promote the fluidity of the weld pool through their chemical composition.
Metallurgical Relevance & Welding Risks
Without flux, oxides can form in the molten metal, leading to porosity and reduced mechanical properties. Too little flux fails to adequately protect the metal and can cause re-oxidation, while too much flux can cause over-deoxidation, resulting in uneven wetting and poor weld quality.
Workshop Practice & Operating Instructions
Use flux at the recommended concentration for the specific metal. Ensure the fluidity of the weld pool is maintained by adding flux. Monitor wetting and adjust flux amount if necessary.