The Hybrid Process of Low-Pressure Carburizing and Metallization (Cr plus LPC, Al + LPC) of 17CrNiMo7-6 and 10NiCrMo13-5 Steels

This paper presents the concept of modification of physicochemical properties of steels by simultaneous diffusion saturation with carbon and chromium or aluminum. The application of a hybrid surface treatment process consisting of a combination of aluminizing and low-pressure carburizing (Al + LPC) resulted in a reduction in the amount of retained austenite in the surface layer of the steel. While the use of chromium plating and low-pressure carburizing (Cr + LPC) induced an improvement in the corrosion resistance of the carburized steels. It is of particular importance in case of vacuum processes after the application of which the active surface corrodes easily, as well as in case of carburizing of low-alloy steel with nickel, where an increased content of retained austenite in the surface layer is found after carburizing.

Automated summary

This paper presents the concept of modifying the physicochemical properties of steels by simultaneous diffusion saturation with carbon and chromium or aluminum. Two hybrid surface treatment processes, Al + LPC and Cr + LPC, were found to reduce the amount of retained austenite in steel and improve the corrosion resistance of carburized steels, respectively. These methods are particularly important for vacuum processes and carburizing of low-alloy steel with nickel.