Armco NITRONIC 50 Stainless Steel provides outstanding corrosion resistance - superior to Types 316, 316L, 317 and 317L in many media. For many applications the 1950 F (1066 C) annealed condition provides adequate corrosion resistance and a higher strength level. In very corrosive media or where material is to be used in the as-welded condition, the 2050 F (1121 C) annealed condition should be specified. High-Strength (HS) NITRONIC 50 bars are useful for applications such as shafting and bolting, but do not quite exhibit the corrosion resistance of the annealed conditions in all environments.
The resistance to intergranular attack is excellent even when sensitized at 1250 F (675 C) for one hour to simulate the heat-affected zone of heavy weldments. Material annealed at 1950 F (1066 C) has very good resistance to intergranular attack for most applications. However, when thick sections are used in the as-welded condition in certain strongly corrosive media, the 2050 F (1121 C) condition gives optimum corrosion resistance.
Stress-Corrosion Cracking Resistance
In common with most stainless steels, under certain conditions, Armco NITRONIC 50 Stainless Steel may stress-corrosion crack in hot chloride environments. When tested in boiling 420/0 MgCI2 solution, a very accelerated test, NITRONIC 50 Stainless Steel is between types 304 and 316 stainless steels in resistance to cracking. There is little difference in susceptibility to cracking whether in the annealed, high-strength (HS), or cold-drawn conditions.
Sulfide Stress Cracking
Both laboratory tests and field service experience have shown that Armco NITRONIC 50 stainless has excellent resistance to sulfide stress cracking in air conditions. NITRONIC 50 in both the annealed and high-strength (hot rolled) conditions has been included in the 1996 revision of NACE Standard MR-01 -75' "Sulfide Stress Cracking Resistant Metallic Material for Oil Field Equipment," at hardness levels up to RC 35 maximum. The resistance to cracking in laboratory tests in synthetic sour-well solution(5% NaCI + ½% acetic acid. saturated with H2S)
NITRONIC 50 Stainless Steel provides a combination of corrosion resistance and strength not found in any other commercial material available in its price range. This austenitic stainless has corrosion resistance greater than that provided by Types 316 and 316L, plus approximately twice the yield strength at room temperature. In addition, Armco NITRONIC 50 Stainless has very good mechanical properties at both elevated and sub-zero temperatures. And, unlike many austenitic stainless steels, NITRONIC 50 does not become magnetic when cold worked.
High Performance Alloys can make hot rolled, cold worked, & strain hardened High Performance Stainless Steel (HPSS) bars in house. Ask for our GFM Bulletin for more information about our bar processing capabilities. We have expanded to enhance product availability.