Microstructure Distribution Parameters for Ferrite-Martensite Dual-Phase Steel

The microstructure was observed and measured on the two kinds of commercially pure sheet iron and DP600 steel so as to reveal its distribution nonuniformity. The distribution of two grain parameters viz the grain size d and grain shape coefficient λ were analyzed on the measurement interval of 0.1, 0.05, and 0.01 μm. Both d- and λ -distributions are nonuniform. These parameters are similarly distributed and consistent with the Gaussian distribution. The nonuniform d- and λ-distributions can be described precisely on a sufficiently large specimen and a reasonable interval length. The nonuniformity of microstructure and materials can be accurately described by constructing the models of dislocation, deformation, and strain-hardening nonuniformity.