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Deoxidation loss via slag formation

Depletion of deoxidizing elements such as silicon and manganese into the slag, thereby reducing their effective concentration in the metallic melt.

When welding, deoxidizers such as silicon and manganese bind the oxygen from the melt and carry it to the surface as slag. If the slag is not properly removed or there is too little deoxidizer in the material, oxygen remains in the weld – this causes pores and weakens the structure, in the worst case cracks. Make sure the slag can flow off cleanly and the filler metal matches the base material. If the weld looks porous or cratered, the deoxidation is usually not right.

MetallurgieSchweißtechnik

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