Material flow analysis for hot-forming of 20MnCr5 gear wheel blanks

摘要

During the manufacture of disk-like gearwheel blanks made of 20MnCr6 (SAE 5120) a characteristic distortion behavior was observed which has been related to the forging process. The steel showed a typical banded structure and a distribution of chemical elements (segregations) perpendicular to rolling direction. When analyzing the micrographs of the forged gearwheel blanks, a significant variation in the material flow was found. In order to clarify the cause of the observed material flow variations and to determine its impact on the distortion potential of the disks, a twofold approach has been applied: a) to determine and to describe the material flow characteristics on basis of micrographs of forged disks and b) to carry out FE-analyses on the theoretical material flow and its parameters. In this contribution results of the material flow analysis are presented and compared with FE-analyses of the forming process.