Manufacturing includes the stage of product verification calculation. At this stage, it is important to have accurate, as close as possible to real mechanical or other characteristics, depending on the type of verification calculation. The object of research is identifying the parameters of the deformation curve of a metal or alloy. A method of constructing a hardening curve is considered, which makes it possible to reduce the number of operations required for this. The study is carried out on the example of a heat-resistant nickel alloy. Method. A method of constructing a hardening curve on a deformation curve is considered an approximation by three parameters: conditional yield stress, ultimate conditional strength, and static modulus of elasticity. The power-law approximation is carried out. A mathematical method of power approximation is used. Results. The average relative error of the approximating curve concerning the considered experimental curves does not exceed 1.56%.