← Glossary

Molybdenum pitting corrosion resistance

Molybdenum increases corrosion resistance against chlorides by improving the oxide layer. It prevents chlorides from penetrating the metal structure and thus protects against local pitting.

Physical-Chemical Mechanism of Action

Molybdenum forms a dense, more stable oxide layer on the steel surface. This layer repels chloride ions and protects the metal from corrosion.

Metallurgical Relevance & Welding Risks

Too much molybdenum can increase hardness and reduce ductility, hurting formability. With the wrong welding procedure, molybdenum can concentrate in the weld and cause localized rust-through.

Shop Practice & Action Items

In chloride-laden environments, use steel grades with higher molybdenum. Watch the welding procedure to keep the weld's hardness and ductility in check. Avoid excessive heat treatment, as it can concentrate molybdenum.

MetallurgieSchweißtechnik

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