The effect of nonisothermal regimes of chemicothermal treatment on the saturation kinetics of alloys was investigated. A series of regimes of nonisothermal processes of carburizing, nitrocarburizing, and nitriding of steels 20KhGNR, 40Kh, and 40KhMFA were studied. Nonisothermal and combined regimes of chemicothermal treatment occured with substantial acceleration of the diffusion process and thickening of the diffusion layer.