Surface severe deformation of the carbon steels

This book is devoted to the modern views of the microstructure evolution in structural and tool carbon steels during the surface severe plastic deformation (SPD). The main focus is on the effects of the nanocrystallization in the near-surface area of the low carbon steel (C 0.05¿0.2%), medium-carbon steel (C 0.35¿0.65%), and high carbon steel (C 1.0¿1.5%). It is reviewed the following advanced surface SPD methods of the metal surfaces in recent years: an ultrasonic impact peening (UIP), high-frequency impact peening (HFIP), air blast shot peening (ABSP), surface mechanical attrition treatment (SMAT), and laser shock peening (LSP). Microstructure evolution before and after SPD was studied by an Optical Microscopy (OM), Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM). The effects of the SPD parameters on the nanocrystalline modification of such main phase components of the carbon steels as ferrite, pearlite and cementite are analyzed. The atomic mechanism of the nanocrystallization is presented. The strain hardening effect by SPD is determined by measuring the near-surface properties.