We used a d.c. sputtering method at high pressures (3–4 mbar) in an argon‐nitrogen gas mixture, to produce hard coating layers of TiN on different steels at temperatures between 300 °C and 450 °C. The composition and the profile concentration of the coated layers has been made using Energy Dispersive X‐Ray analysis, EDX, and Auger Electron Spectroscopy, AES. We have analyzed the influence of the deposition parameters on the mechanical properties. Vickers micro hardness measurement showed an increase of about 125% over D3 type steels hardness. The used method is very effective in order to improve the superficial properties of these steels.