420 J2 is a general purpose stainless steel containing medium quantity of carbon. It has good corrosion resistance qualities in mild atmosphere, domestic and industrial environments. It is resistant to ammonia, blood, carbonic acid, crude oil, detergent solutions, dilute nitric acid, fresh water, food acids, many petroleumproducts, steam and vinegar etc. It has good strength and reasonable impact resistant properties in both hardened and tempered conditions as compared to 440 grades.
It is also called Surgical Steel, because it is being used in production of surgical instruments on large scale around the world, due to its good corrosion resistant and easily machining qualities. It is also being used in cutting tools like; Knifes, Daggers, Swords, Haircutting Scissors and Domestic scissors. It’s grinding is easy and it produces a fine, vivid and smooth polished surface.
420 steel, due to its excellent hardenability, it is capable of getting hardened up to 54 HRC Rockwell or higher depending upon carbon contents. Small sections can be air cooled and larger sections should be oil quenched for maximum hardness.
