A new multilayered nanostructured composite material produced by assembling SMA-treated thin plates

Abstract : Surface mechanical attrition treatment (SMAT) can produce a nanometer-grained surface layer without porosity and contamination on a bulk stainless steel. The nanostructured layer has high strength that contributes to an overall increase in the mechanical properties of the nanostructured sample. In this study, a new nanostructured composite was developed by assembling three SMA-treated thin plates. An FEM model based on nanoindentation data was established to simulate the stress-strain relationship. The simulation and the experimental tension curve correspond well. Moiré interferometry was used to observe the tensile behavior of the new composite in real time. A tension test conducted on a specimen consisting of three 500~μm thick SMA-treated sheets showed that the yield stress is much higher than that of a bulk-treated sample of the same total thickness. Based on these results, the new multilayer composite would seem to be a promising structural material due to its high strength/weight ratio.