26th International ESAFORM Conference on Material Forming, ESAFORM 2023, Krakow, Polonya, 19 - 21 Nisan 2023, cilt.28, ss.899-908
Rotary swaging is an ascendant forming method for manufacturing axisymmetric parts. High production rate with excellent net shape forming is achieved in recent automation developments. However, precise machine design and tailored process developments are necessary to transfer the high impact type forming loads to workpiece efficiently. The failure of this transfer results in high vibrations of the machine structure and poor product quality, due to the impact loads with high frequencies. The centerpiece of the process development to prevent these disruptive effects is to resolve die specifications such as shape and surface properties. In general forming applications, surface roughness of the dies is perceived as a disruptive element for the product quality and only a small amount is provided to settle lubricants. However, for rotary swaging applications, an optimized surface roughness to increase the load transfer between the die and the workpiece without disrupting the final product surface quality is essential. In this study, for a fixed die shape, the relation between the die surface roughness and the product quality is investigated for macro rotary swaging applications. In particular, the effective transfer of the forming forces to the workpiece is analyzed by using finite element analysis within the scope of surface friction. Consequently, a die set with roughened surface conditions is manufactured by using a novel technique. Real process trials are conducted to validate the results of the analysis.