Electrochemical studies on the film formed by direct nitridation of AA2024 in a KNO3 salt bath at low temperature

► New thermo-chemical low-temperature nitride synthesis route in potassium nitrate salt in presence of ultra pure nitrogen atmosphere at 475 °C was proposed. ► The corrosion protection performance offered by this route was very promising for stainless steel. However, limited protection was observed when applying such route to aluminum substrates. ► Removing the scale formed due to nitriding process by quenching is essential for better surface resistance. ► The paper provided an attempt towards determining the optimum conditions for synthesis of nitride coatings of an acceptable corrosion resistance for AA2024 substrate.