Study of the structural inhomogeneity of bimetal layers at the yield plateau stage

Abstract

The paper studies the kinetics of Chernov–Luders band propagation of bimetallic material on the yield plateau at the microscale level. The localization patterns of plastic deformation in the process of uniaxial tension are obtained by noncontact method of recording the fields of displacement vectors. Microstructure of the interfaces studied by atomic force microscopy showed that in the direction of the pearlite steel to the austenitic form there are structural components: the weakened zone of the ferrite layer; hardened section of the ferrite layer dark-pickling layer from the side of austenitic steel. Plastic deformation of a bimetal begins from the nucleation of the Luders band on the boundaries of the bimetal on stress raisers with higher hardness due to the diffusion effect. In the main layer the Luders band is limited to a pair of fronts moving in opposite directions along the bimetal axis with different velocities. The cladding layer does not suppress the formation of Luders bands, leads to an increase in the propagation velocity of Luders band fronts in the base layer and reduces the Luders band propagation in all bimetal layers.The paper studies the kinetics of Chernov–Luders band propagation of bimetallic material on the yield plateau at the microscale level. The localization patterns of plastic deformation in the process of uniaxial tension are obtained by noncontact method of recording the fields of displacement vectors. Microstructure of the interfaces studied by atomic force microscopy showed that in the direction of the pearlite steel to the austenitic form there are structural components: the weakened zone of the ferrite layer; hardened section of the ferrite layer dark-pickling layer from the side of austenitic steel. Plastic deformation of a bimetal begins from the nucleation of the Luders band on the boundaries of the bimetal on stress raisers with higher hardness due to the diffusion effect. In the main layer the Luders band is limited to a pair of fronts moving in opposite directions along the bimetal axis with different velocities. The cladding layer does not suppress the formation of Luders bands, leads to an incre...