Transformation of heterophase inclusions “dispersed phases are in non-metallic matrix” in steels under laser action
Melting and crystallization of heterophase non-metallic inclusions “dispersed phases are in non-metallic matrix” was investigated. Mechanism of melting of the inclusions “dispersed phases are in non-metallic matrix” and inclusion-matrix boundaries under contact laser melting with steel matrix in the conditions of abnormal mass transfer connecting with formation of zones with high dislocation density and also with electron and electro-magnetic interaction between inclusion and steel matrix was proposed. That allows to create the possibilities for the influence on the inclusion-matrix boundaries and also on the chemical and phase composition of surface layer of non-metallic inclusions “dispersed phases are in non-metallic matrix”. Peculiarities of structure of non-metallic inclusions after speed crystallization were investigated. It was shown that under laser action the initial structure of inclusion-steel matrix boundaries transits into unstable equilibrium high-energy condition that cause development of the dissipation processes connecting with aspiration of system inclusionmatrix to the state with minimum of the free energy. In the result of the system inclusion-matrix transits to the state of unstable equilibrium which determines structure and properties of laser-quenched interphase boundary. Processes of melting, fusion and dissolution of nonmetallic inclusions “dispersed phases are in non-metallic matrix” and also of the melting of steel matrix play the great role in transformation of interphase inclusion-matrix boundaries under laser action.