LAUSR

Abstract The formation mechanism of stress-induced anisotropy in Fe73.5Cu1Nb3Si13.5B9 alloys is studied in-situ using synchrotron radiation XRD. The evolution of the diffraction spectra during the nanocrystallization and relaxation annealing of the ribbon samples is shown. The results reveal that the stress-annealed sample possess a positive and larger structural anisotropy Δ q compared to the insignificantly negative Δ q in the sample annealed without stress. Macroscopic strain (e) and microscopic strain (e) measurements reveal that the structural anisotropy of the stress-annealed sample is released after the annealing process as residual strain, which confirms the stress-induced anisotropy to be magnetoelastic in origin. Relaxation annealing of the stress-annealed sample reveals that the structural anisotropy ( Δ q ) , induced transverse magnetic anisotropy ( H k ) , and anisotropy energy ( K u ) are significantly affected while the macroscopic strain is insignificantly affected. We have then suggested the origin of stress-induced anisotropy can be attributed to magnetoelastic effects due to residual strains.