Deformational grain grinding of alloyed steels microstructure at non-stationary intense plastic deformation by explosion
Dependence of grain size of alloyed high-strength steels of austenitic, bainitic, maraging classes on temperature and degree of deformation at non-stationary intensive plastic deformation by explosion has been studied. A model which enables to calculate dispergating limit value considering dependence of coefficient of grain-boundary diffusion on degree of deformation and temperature is constructed. The results of calculations by the offered formula and their comparing to experimental data show satisfactory coincidence. A rejection is 3-5%. It is set that the intensive growing shallow under the action of high-speed flowage the explosion of alloyed high-strength steels takes place at the degrees of deformation 20-30%. Increase of degree of deformation to 30-40% does not cause the change of size of grain. At deformations more than 40-50% the accumulated flowage causes additional local warming-up of material and development of recrystallizational processes, sizes of grain increase as a result. At deformations higher 50-60% appearances of cracks in materials is possible.