In this paper, we apply the extended direct algebraic method to examine the soliton solutions as well as hyperbolic and trigonometric functions solutions of convective–diffusive Cahn–Hilliard equation describing the dynamic of separation phase for ternary iron alloys of (Fe ‐ Cr ‐ Mo) and (Fe ‐ X ‐ Cu). The outcomes reveal that our technique is very dynamic and straightforward. It is observed that the obtained exact solutions of this model are new in the literature. Moreover, various 2D and 3D graphs of the obtained solutions are presented to examine the physical understanding of the obtained results.