Effect of shear derformation in rail steels

Description of the module:

During the time of application rails undergo enormous stresses and strains. Especially on the surface a severe deformed layer is formed. This region is the origin of the most phenomena like headcecks, ratcheting and white etching layers, leading to wear or even to a breakdown of the rail. A deep understanding of the properties of the highly deformed material is vitally important, both for an exact plan of the maintenance of the rail track  and for a methodic development of the used steels.

The quite new methods of severe plastic deformation are promising tools to produce samples with deformations to strain levels of some thousand percents. The advantage of these samples compared to samples for used rails is primarily the exact knowledge of the deformation history and the reproducibility. 

The goal of the module is a precise characterization of the severe deformed material in matters of microstructure evolution and crack introduction and therefore gain new insight in the behavior of the material in application.