Stainless steels are economic choices of oilfield production equipment for sweet and mild sour environments, even though lacking hardness, abrasive wear properties, and galling resistance. In this short investigation, surface diffusion treatments such as liquid nitrocarburizing and plasma nitriding are applied to different grades of high-chromium alloys, specifically 13Cr (UNS41000), S13Cr (UNS41425), 17-4PH (UNS17400), 316 (UNS31600), as well as ASTM A532 white irons. The alloy corrosion behaviors were successfully established in different environmental chloride-rich conditions. Tribological properties were investigated by microindentation, correlated to (1) microstructural evaluations by SEM, EDS, and XRD, and (2) corrosion properties established by cyclic polarization testing, salt-sprays, and a variety of immersion tests. It is found that the effect of surface modifications predominantly depends on the selected alloys, with consistent reduction in passivation for all alloys.