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Stainless steel profile manufacturer why to use nitrogen when welding stainless steel pipe

Stainless steel profile manufacturer why to use nitrogen when welding stainless steel pipe

Time:2022-03-22 Source:WUXI JIANUO SPECIAL STEEL CO.

Stainless steel profile manufacturer why to use nitrogen when welding stainless steel tubes? The role of nitrogen in stainless steel welded pipe is reflected in three aspects: stainless steel matrix structure, mechanical properties and corrosion resistance properties. Studies have shown that nitrogen is an element that very strongly forms and stabilizes austenite and expands the austenite phase. It can replace some of the nickel in stainless steel, reduce the proportion of ferrite in the steel, and make austenite more stable. Even under cold working conditions, it prevents the precipitation of harmful intermetallic phases and avoids martensitic phase transformation.

The effect of nitrogen on the mechanical properties of stainless steel is manifested as follows: nitrogen increases the strength of stainless steel without reducing the plastic toughness of the material; nitrogen can improve the creep resistance, fatigue resistance, wear resistance and yield strength of stainless steel. As one of the elements to improve corrosion resistance, nitrogen can form NH4 + in the voids, eliminating the H + generated during the formation process, suppressing the pH, thus inhibiting the occurrence of pitting and the rate of dissolution of metal in the hole, and improving local corrosion performance.

This is why stainless steel tubes need to be welded with nitrogen, which not only makes the weld stronger, but also improves the performance of the tube.