The lightweight Fe–Mn–Al–C steels have drawn considerable attention from the literature due to their outstanding combination of high ductility and specific strength. Although the mechanical behavior of such steels has been extensively studied, the effect of Al when no C and Si are added has not been investigated in detail. For this reason, the main objective of this work was to study the microstructural evolution and mechanical behavior of carbon and silicon-free high-Mn steels with different aluminum contents. Alloys with 0, 2.5, and 5 wt. % Al were processed by spray forming to ensure high homogeneity and a fully austenitic microstructure. Cold rolling and annealing were performed to obtain a fine grain-sized material. The mechanical properties were similar regardless of the Al content, especially the work hardening rate. Deformation twinning and strain-induced phase transformation were not observed for any of the compositions. Additionally, a dislocation cell-like structure was observed for all of the alloys indicating that the Al additions did not change considerably the dislocation behavior, even though it considerably changed the estimated Stacking Fault Energy (SFE) value for all the alloys studied in this work.
Ultrafine eutectic Ti-based nanocomposite alloys exhibit high mechanical strength (1,800-2,500 MPa), elastic modulus nearest human bone (50-110 GPa) and good corrosion resistance due to a combination of soft β-Ti (bcc) matrix and hard/refined TiFe and/or Ti3Sn intermetallic particles. The present study focuses on the production and characterization of Ti-Fe-Nb-Sn eutectic alloys using biocompatible stabilizer elements, such as Nb, Fe and Sn. Different fabrication techniques based on rapid solidification and with further evaluation of the generated properties may be highlighted considering the application of these alloys as implant material. In the present investigation, the proposed processing routes comprise single tracks and coatings (overlapped tracks) by laser melting of prealloyed powders of the Ti66Fe20Nb8Sn6 alloy deposited into a Ti substrate. To select this composition, three Ti-Fe-Nb based compositions of interest were originally generated under bulk conditions by using a suction casting apparatus and were further evaluated. All samples were analyzed by metallography, X-ray diffraction (XRD), scanning electron microscopy (SEM-EBSD and SEM-EDS), microhardness, nanohardness and elastic modulus. The results showed that the proportions of the formed TiFe and Ti3Sn intermetallic particles dispersed within the soft -Ti matrix play a fundamental role on the final properties. Lower elastic modulus (E~72 GPa) is associated with the Ti66Fe20Nb8Sn6 bulk alloy, whereas laser clad coatings for the Ti66Fe20Nb8Sn6 alloy showed a broad range of nanohardness (4.8-8.0 GPa) and elastic modulus (98-150 GPa) depending on the related laser power and scanning speeds.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.