Luis B. Laporte: homenajes a su memoria

Documento de valor histórico que recopila discursos y remembranzas acerca del Ingeniero Luis B. Laporte, su vida, su obra, sus acciones

Influence of Cobalt Substitution on Hyperfine Interactions in (Fe1−xCox)76Mo8Cu1B15(Fe_{1-x}Co_x)_{76}Mo_8Cu_1B_{15} Alloys

The effect of cobalt substitution on structure, magnetic behaviour, magnetic arrangement, and hyperfine interactions in $(Fe_{1-x}Co_x)_{76}Mo_8Cu_1B_{15}$ (x = 0, 0.1, 0.2, 0.25, 0.5) is studied by the Mössbauer spectrometry for both as-quenched and annealed alloys. Partial substitution of Fe by Co resulted in an enhancement of the average value of hyperfine magnetic field distributions as a function of x probably due to higher magnetic moment of Co. After annealing, a two-phase nanocrystalline structure composed of amorphous matrix and bcc-FeCo nanocrystallites was observed. Mössbauer spectra were fitted with up to four six-line patterns of narrow lines assigned to different number of Co nearest neighbours inside a bcc-FeCo lattice

Effects of Heavy-Ions on Soft-Magnetic Metallic Glasses Studied by Diffraction of Synchrotron Radiation

In this work, influence of $^{238}$U swift (5.9 MeV/u) heavy ions on the as-prepared Fe–Cu–Nb–Si–B metallic glass was investigated by in situ temperature X-ray diffraction of synchrotron radiation. It was observed that ion strongly affected the temperature evolution of the parameters of the first diffuse peak. It is hypothesizedthat ion irradiation induced structural rearrangement that increased the degree of disorder of the amorphous structure. During heat treatment, structural relaxation and annealing out of this ion-induced degradation took place. Consequently, the original structure was recovered as demonstrated by the behaviour of the first diffuse peak broadening and devitrification process

Structural modifications of swift-ion-bombarded metallic glasses studied by high-energy X-ray synchrotron radiation

Modifications of structural arrangements including relaxation processes were investigated in swift-heavy-ion-bombarded Fe73Cu1Nb3Si16B7 metallic glass. The irradiation of as-quenched amorphous ribbons was accomplished with 3 MeV u−1 (u is atomic mass unit) and 11.1 MeV u−1 Au ions with total fluences of up to 1 × 1013 ions cm−2. Specimens irradiated with 3 MeV u−1 ions were subsequently annealed for 4 h at 350 °C. Ion-irradiated samples including those heat-treated were studied using in situ temperature-dependent diffraction of high-energy X-ray synchrotron radiation (wavelength of 0.020689 nm). Cyclic heating–cooling regimes were applied during the measurements. A tendency towards a higher degree of disorder was revealed as a function of the ion fluence in both types of alloys. During the first heating–cooling cycle, a remarkable hysteresis is observed in the position and line width of the first diffraction peak, especially in the as-quenched irradiated alloys. The hysteresis increases with rising ion fluence but vanishes completely after the first heating–cooling cycle. No hysteresis is found in the irradiated and subsequently annealed alloys. The irradiation-induced structural modifications have some features similar to the effects caused by mechanical deformation