US 12,435,406 B2
Activation of self-passivating metals using reagent coatings for low temperature nitrocarburization in the presence of oxygen-containing gas
Frank Ernst, Cleveland Heights, OH (US); Todd Johns, Solon, OH (US); Ronald Edmonson, Munroe Falls, OH (US); Cyprian Adair William Illing, Cleveland Heights, OH (US); Peter C. Williams, Cleveland Heights, OH (US); and Christina Semkow, University Heights, OH (US)
Assigned to SWAGELOK COMPANY, Solon, OH (US)
Filed by Swagelok Company, Solon, OH (US); and Case Western Reserve University, Cleveland, OH (US)
Filed on Apr. 28, 2022, as Appl. No. 17/731,437.
Claims priority of provisional application 63/180,744, filed on Apr. 28, 2021.
Prior Publication US 2022/0364216 A1, Nov. 17, 2022
Int. Cl. C23C 8/22 (2006.01); C23C 8/26 (2006.01); C23C 8/32 (2006.01)
CPC C23C 8/22 (2013.01) [C23C 8/26 (2013.01); C23C 8/32 (2013.01)] 21 Claims
 
1. A method for low-temperature interstitial case formation on a self-passivating metal workpiece comprising exposing the workpiece in a heated gaseous environment comprising atmospheric oxygen to pyrolysis products of a nonpolymeric reagent comprising at least nitrogen and carbon.