Slag removal auxiliary
Slag removal aids are chemical or mechanical means that facilitate the detachment of solidified slag from the weld surface. They prevent porosity and improve surface quality.
Physico-chemical mechanism of action
Slag removal aids react chemically with the slag or mechanically separate it from the weld. Chemical aids bind oxygen and prevent the slag from adhering firmly. Mechanical aids like toothed wire brushes or grinding remove the slag by mechanical force.
Metallurgical relevance & risks in welding
Without effective slag removal, pores can form in the weld, which impairs strength and toughness. Additionally, trapped slag can lead to hot cracking or damage the surface. Using slag removal aids reduces these risks and improves the overall quality of the weld.
Workshop practice & instructions
Use chemical slag removal aids like silicon or potassium hydroxide in the final seconds of cooling. Mechanical aids like toothed wire brushes or grinding should be applied after the weld has dried. Make sure the aids are not too aggressive to avoid damaging the surface.