Dislocation densities in a low-carbon steel during martensite transformation determined by in situ high energy X-Ray diffraction

The evolution of the dislocation densities in martensite and austenite during quench a low-carbon (0.215 wt% C) steel is investigated situ by mean High Energy X-Ray Diffraction experiment on synchrotron beamline. line configuration offers an excellent time resolution well adapted to studied martensitic transformation kinetics. density dislocations increases as proceeds confirming that are not homogeneously distributed between laths agreement with some recent post-mortem observations. resulting spatial distribution associated strain-hardening support views assuming lath heterogeneous microstructure behaves “multiphase” aggregate. In austenite, increase even more significant meaning also hard phase, contradicting theories attributing films retained major role plasticity martensite.