nitrogenation
/ˌnʌɪtrədʒɪˈneɪʃn/ /nʌɪˌtrɒdʒɪˈneɪʃn/noun
The action or process of combining or treating a substance with nitrogen; (Metallurgy ) = nitridation.
Origin
1920s; earliest use found in Journal of the Iron and Steel Institute. From nitrogen + -ation.