XM-19 stainless steel is a high – strength nitrogen – strengthened austenitic stainless steel, also known as Nitronic 50 or Fermonic 50, with the UNS number S20910. It has excellent corrosion resistance and mechanical properties, and is widely used in many fields such as marine, chemical, and aerospace. The specific introduction is as follows:
Chemical Composition: Carbon (C) ≤0.06%, Silicon (Si) ≤0.75%, Manganese (Mn) 4.00 – 6.00%, Chromium (Cr) 20.50 – 23.50%, Nickel (Ni) 11.50 – 13.50%, Molybdenum (Mo) 1.50 – 3.00%, Nitrogen (N) 0.20 – 0.40%, Vanadium (V) 0.10 – 0.30%, Niobium (Nb) 0.10 – 0.30%.
Physical Properties: The density is about 7.8g/cm³, and the melting point is between 1415℃ and 1450℃. It has good high – temperature oxidation resistance, and remains non – magnetic even after severe cold working.
Mechanical Properties: In the solution – annealed state, the tensile strength is ≥690N/mm², the yield strength is ≥380N/mm², the elongation is ≥35%, and the Brinell hardness is ≤241HB. Its yield strength is almost twice that of 304 and 316 stainless steels, and it has good mechanical properties in both high – temperature and low – temperature environments.
Corrosion Resistance: Through the reasonable combination of chromium, molybdenum and nitrogen contents, its Pitting Resistance Equivalent Number (PREN) exceeds 34, which is much higher than the standard 3xx series stainless steels with a PREN of 25. It shows better resistance to pitting, crevice corrosion and stress – corrosion cracking than 316, 317L, etc. in many media.
Processing Performance: XM – 19 is easy to process and form, and can be processed by cold – working and hot – working processes such as cold rolling, cold heading, hot rolling and forging. It can also be welded by conventional welding methods such as TIG, MIG, etc. However, before welding, it is necessary to clean the surface oxides and select appropriate welding parameters.
Application Fields: Due to its excellent comprehensive properties, XM – 19 is widely used in the oil and gas industry for down – hole equipment, in the marine industry for marine pumps, valves, masts, etc., and can also be used in food processing equipment and valves and fittings in the pulp and paper industry.