Friction analysis during deformation of steels under hot-working conditions

An original multiscale friction analysis is developed to characterize the interfacial phenomena during hot forging contact conditions in manufacture of wheels for railway industry. Hot upsetting sliding tests and roll-on-disc are performed reproduce tribological at meso micro-scale. Crushed embedded oxides found be present on sample's surfaces. Stick-slip occur due accumulation crushed oxides. This transform from a lubricant/oxide configuration an oxide/oxide condition. Microanalysis measurements specimen's wear tracks clearly show that lubricant layer broken down transferred tool specimen surface by means accumulated oxide particles.