The Microstructures in 0.20%C Carbon Steel Induced by High-Current Pulsed Electron Beam

In order to investigate superfast deformation behavior of metal, annealed 0.20%C carbon steel was irradiated with high-current pulsed electron beam (HCPEB). The microstructures of irradiated samples were investigated by using X-ray diffraction (XRD), optical microscopy and transmission electron microscopy (TEM). The experimental results showed that stress of about 1 GPa order was introduced in the irradiated surface layer, which led to severe plastic deformation on the irradiated surface. Both of the complicated configurations of tangle dislocations and dislocation cells were formed within the sublayer. Simultaneously, dislocation loops companied with the dislocations configurations were also produced. In the situation of multi-pulses, characterization by TEM also revealed that the sublayer consisting of some region with the glassy and nanocrystalline structure. It is suggested that the high-level stress and strain rate induced by HCPEB irradiation could cause the shifting of whole atomic planes synchronously. This is the more possible mechanism of the formation of the glassy and nanocrystalline structure.