This work was focused, by using computer aided engineering application (SolidWorks) and structural simulation (SolidWorks SIMULATION), on obtaining a technical and economic strength indicator used in the analysis of metallic material choice from which is made active body large diameter disc knife type, that equips the technical equipment for soil tillage on trees row, while cuttings root for moderating growth of shoots and precision foliar fertilization. For this purpose, on the 3D parametric modeling were selected from the software library various metallic materials, followed by finite element analysis (FEA) which was carried out to simulate the distributions of stress and strain on the body active. Based on the resulting data, were determined the reports price- coefficient of resistance for the materials analyzed. Comparing these indicators led to the selection of a material that has high resistance under a price as low as possible. Analysis based on technical and economic choice of a metallic material reduces the time validation of the design, by eliminating the realization and physical testing, and allows management to determine the existing resources in the company in order to use their total for achieve economic and financial results as high.