Abstract: The influence of various austenitizing temperatures on the structure and property of steel is introduced from the result of deformation-hardening experiment of steel 25Mn2V. Through SEM observing its microstructure and fracture and measuring its inner loss conclusion is reached that the main reason of deformation hardening is carbon atoms segregation at the initial stage of strain aging. The rise in quenching temperature within certain range will increase the strength and ductility of low carbon alloy steel and improve the welding seam's structure and property of welding parts to prevent breaking.

Key words: Aging-hardening, Deformation, Quench, Temper