Microalloyed Steels Laminated Composites Processed by the High‐Strain Rate Compression Tests

Abstract

Multilayered metal‐to‐metal (MM) composites have been gathering much interest in the last decades because of its extraordinary mechanical properties. In the present study, the microstructural changes and mechanical behavior of two grades of microalloyed steels, that is, ferrite (M_F) and austenite (M_A), in the MM composite systems have been investigated and analyzed. In the present study, the Surface Mechanical Attrition Treatment (SMAT) is applied to introduce initial gradual microstructural changes in steel plates. Considerable microstructural refinement occurs as a result of the accumulated plastic deformation during the SMAT process. In the next step, specimens are again deformed by compression then stocked and compressed using drop weight test with a high strain rate of 1000 s−1, resulting in equivalent plastic strain of ϵ = 0,8.It is found that plastic pre‐deformation, significantly affected the distributions of the equivalent strains and stresses in both materials, but differently. Bonding quality of the laminated MM composites, using SEM and EBSD technique, is analyzed. The rheological properties of particular layers in the investigated M_F and M_A multilayered composites are defined using hardness measurements. Such a procedure demonstrated the work hardening gradients of the samples that are subjected subsequently to the SMAT, high‐strain rate compression, and bonding processes.