Crevice corrosion prevention
Design and procedural measures to avoid narrow gaps and incompletely passivated areas. It minimizes the risk of concentration cells.
Crevice corrosion occurs where moisture or aggressive media can settle in narrow gaps – for example between two sheets or under weld beads. The passive layer breaks down there because oxygen cannot reach it, and the material rusts from the inside out. When welding, this means: you must avoid crevices where water or dirt can collect. Clean, fully penetrated welds are essential. If you are working with stainless steel, make sure the heat input is not too high, otherwise you will destroy the corrosion resistance in the heat-affected zone. In practice, this means: finish the weld cleanly, leave no undercuts or root gaps. For critical components, you can pickle or passivate the surface after welding to rebuild the protective layer.