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Silicon carbide layers were fabricated using self-propagating high-temperature synthesis of binary silicon-carbon based reactive multilayers. The silicon and carbon bilayers were fabricated with two different bilayer thicknesses. They are deposited by magnetron sputtering in an alternating layer system with a total thickness of 1 μm. The entire system is annealed by rapid thermal annealing at different temperatures ranging from 500 to 1100 °C. From XRD analysis we could find that the formation of the silicon carbide phase was initiated from 700 °C. With increasing bilayer thickness the silicon carbide phase formation was partially suppressed by the silicon recrystallization due to resulting lower carbon diffusion into silicon. The transformation process proceeds in a four-step process: densification/recrystallization, interdiffusion, nucleation and transformation. From this, it was noted that when compared to low bilayer thickness samples, the formation of the silicon carbide phase is delayed with increasing bilayer thickness and needs higher reaction initiation temperatures. Graphical abstract

Chromium and tin substituted strontium hexaferrites {SrAl4(Cr0.5Sn0.5)xFe8 − xO19 with x = 0.0, 0.2, 0.4, 0.6, and 0.8} were synthesized by the sol-gel auto-combustion route. Rietveld refinement of X-ray Diffraction patterns was performed to reveal the phase purity, crystal structure, and unit cell parameters, such as lattice constants, bond angles, and bond lengths. Types of bonds were also verified using Fourier Transform Infrared Spectroscopy. Scanning Electron Microscope was used to explore the effect of substitution on the microstructure. Furthermore, the effect of Cr+3 and Sn+4 substitution on magnetic properties was studied using the Magnetic Property Measurement System. The relationship among the allocation of cations over the 5 sublattices of Fe+3 with substitutions was also analyzed. The saturation magnetization and magnetocrystalline anisotropy were calculated by the “Law of Approach to Saturation magnetization (Ms)” technique at room temperature. The maximum Br and (BH)max was theoretically calculated about 7.62 kG and 7.60 MGOe, respectively, for x = 0.60 composition. Cr-Sn substituted Sr-hexaferrite can be proposed for applications as a permanent magnet with a good deal of consistency.