In order to improve the friction and corrosion resistance of the 38CrMoAlA steel under acidic conditions,the CrN and Cr/CrN coatings were deposited on the 38CrMoAlA steel and nitriding 38CrMoAlA steel substrates by the multiarc ion plating technology.The microstructure of the coating material was characterized by XRD,SEM and other methods,and the mechanical properties,electrochemical properties and tribological properties of the coatings were studied by hardness and binding force test,open circuit potential test and polarization performance test,and friction and wear test.It is found that CrN and Cr/CrN coatings have higher open circuit potential,smaller corrosion current density,and the coating surface is slightly passivated,so CrN and Cr/CrN coatings can improve the corrosion resistance of 38CrMoAlA steel in acid condition.The friction coefficient and wear rate of CrN and Cr/CrN coatings are lower than those of 38CrMoAlA steel and nitriding 38CrMoAlA steel,indicating that both coatings can improve the tribological properties of 38CrMoAlA steel.Although the hardness of the Cr/CrN coating on nitriding 38CrMoAlA steel is slightly lower than that of the CrN coating on 38CrMoAlA steel,it has higher bonding force between coating and substrate and better friction and corrosion resistance.