A multiscale approach for the deformation mechanism in pearlite microstructure: Numerical evaluation of elasto-plastic deformation in fine lamellar structures

Elasto-plastic deformations in the microstructures of pearlite are studied by finite-element analyses. Various models for the lamellar structure are made and the material properties of cementite and ferrite are established. Deformation of a bare specimen of cementite is unstable immediately after the yield point, while cementite lamellae show some stability when they are layered with ferrite. When higher values of yield stress and strain hardening are used for ferrite phase, cementite deforms well beyond the elastic range and the distribution of plastic strain is not concentrated. These results show that not only the layered structure but also the improved mechanical property of fine lamellae of ferrite contribute largely to stable deformation in the pearlite microstructure.