Mechanical properties and spinodal decomposition of TixAl1 − x − yZryN coatings

A 64-atom special quasirandom structure (SQS) has been employed to model the A0.5B0.25C0.25D, i.e., the TixAl1 − x − yZryN with x=0.5 and y=0.25, coating alloys in rock salt structure. Elastic constants are calculated by an efficient stress-strain method. The presence of Zr in TixAl1 − x − yZryN weakens the directional (covalent) nature of the nearest bonds and decreases the hardness of coatings. Additionally, the increase of Zr content changes Zener's elastic anisotropy ratio (A) from (A>1) to (A<1), resulting in the alteration of spinodal decomposition from 〈100〉 to 〈111〉 direction.