The Use of SAW, RAM and PIV Decision Methods in Determining the Optimal Choice of Materials for the Manufacture of Screw Gearbox Acceleration Boxes

This article investigates material selection for components in worm gear reduction gearboxes, focusing on the worm shaft, gearbox casing, and worm gear body. The screw shaft’s and worm gear body’s material selection involved evaluating six criteria: hardness, tensile strength, yield strength, relative elongation, relative contraction, and impact strength. Gearbox casing materials were selected based on five parameters, including tensile strength, yield strength, relative elongation, impact strength, and hardness. The authors employed three Multi-Criteria Decision-Making (MCDM) methods, Simple Additive Weighting (SAW), Root Assessment Method (RAM), and Proximity Indexed Value (PIV) to assess material choices. Various methods, including Entropy, Logarithmic Percentage Change-driven Objective Weighting (LOPCOW), and Equal, determined weights for the criteria. Remarkably, consistent optimal material types emerged across all MCDM and weight determination methods, showcasing the robustness of the results. For screw shafts, C35 steel was identified as the optimal type. GC120- 04 stood out among nine materials for gearbox casing production. C35CrMo was determined as the best type among eight steel types for manufacturing the worm gear body. In summary, this study provides a comprehensive and objective approach to material selection for worm gear reduction gearbox components, offering valuable insights for decision-making in the mechanical engineering industry.