Magnetic properties were measured for amorphous alloys which were produced by single and double roll techniques, and annealed in a magnetic field. It is shown that the coercive force depends on tape thickness and on frequency of the magnetic field and the magnetic core loss are larger in the amorphous alloys produced by single roll than in those by double roll. These phenomena are discussed in terms of the differences in quenching rate, surface roughness and inner stress distribution induced during the rapid quenching in both the production methods. It is shown that the inner stress distribution is the dominant factor for the phenomena.

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Uniaxial anisotropy, coercivity and permeability have been investigated in zero magnetostrictive Co-Fe-B and Fe-B amorphous films. The amorphous films of about 1μ in thickness have been prepared by r. f. co-sputtering technique. In as-prepared films, the magnitude of the uniaxial anisotropy is 1-3×10³ erg/cm³. By annealing in a static field at 200-300°C, the anisotropy increases to 9×10³ and 5-10³ erg/cm³ in Co-Fe-B and Fe-B film, respectively. When the films are annealed in a rotating field at 300°C, the anisotropy is almost eliminated.
The coercivity H_c of Co-Fe-B films can be reduced to 0.02 Oe by annealing either in a static or rotating field, while H_c of Fe-B films depends on the type of the annealing field; low coercivity of 0.04 Oe is obtained only when the films are annealed in a static field.
The Co-Fe-B films annealed in the rotating field exhibit very high permeability particularly in high frequency range (-5000 at 1MHz, -3500 at 50MHz). The high permeability is obtained reproducibly and stable to the field annealing at 100deg;C for one hour.

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A systematic study of electrical resistivity ρ in amorphous (Fe, Co, Ni) _100-xB_x alloys has been carried out in a temperature range from 4.2K to 1200K in order to clarify microstructures of the amorphous alloys. The value of ρ at 4.2K varies from 1.10 to 1.25×10^-4Ω·cm in Fe-B, 0.64 to 1.25×10^-4Ω·cm in Co-B and 0.75 to 1.75×10^-4Ω·cm in Ni-B alloy systems with increasing boron concentration. In the Ni-B system temperature coefficients of the electrical resistivity become smaller with increasing boron concentration and change its sign from positive to negative at 38 at%B. Resistivity minima at low temperatures have been observed in these three systems with relatively boron-rich content. The composition dependence of ρ is explained qualitatively by considering that ρ in amorphous alloys consists of ρ_am and ρ_in, where ρ_am is attributed to an amorphous structure and ρ_in is closely connected with an Invar property.

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An asymmetric hysteresis. loops in ferrimagnetic Gd-Co amorphous films has been observed using polar-Kerr magneto-optic effect. In comparison with the normal hysteresis loops the asymmetric loops have two coercive forces, and H_c'. The difference between these two coercive forces, ΔH is a function of the previous applied field (H_a) and has a different temperature dependence in the range of temperature lower and higher than compensation temperature (T_comp). Near T_comp, the ΔH is very small. The asymmetric hysteresis loops can be explained in terms of the coercive force dispersion model. A study of the change of the coercive forces in multilayered films (Gd-Co+SiO₂+Tb-Fe) in comparison with the single layer (Gd-Co) is also given.

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Amorphous rare-earth transition-metal multilayered films are proposed for a magnetooptic storage medium. The multilayered films are composed of a writing layer with high coercivity and low Curie temperature and a reading layer with low coercivity and high Curie temperature. Using Tb-Fe (500 Å) and Gd-Fe (150-300 Å) layers for writing and reading, respectively, the properties of the multilayered films are examined for magnetooptic memories. In exchange coupled films, the coercivity of Gd-Fe layer is much increased to several kOe. As a result of the strong exchange coupling, the films show the low writing energy and high bit density nearly the same as Tb-Fe films, and exhibit also reasonable magnetooptic effect as high as Gd-Fe films. In magnetostatically coupled films, though the magnetization curves are substantially the same with the sum of those of independent two layers, small bits of 1.5 μm in diameter written on Tb-Fe layer can be transfered on Gd-Fe layer after the application of an appropriate external field.

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Temperature dependence of the electrical resistivity and the galvanomagnetic effect for amorphous rare earth-transition metal ferrimagnetic films between 1.5K and 700K has been studied. Thc absolute value of resistivity is about 270-400 μΩ·cm and the temperature coefficient of resistivity is negative and 10^-4/K for Fe alloys and 10^-5/K for Co alloys. The temperature characteristic of resistivity is divided into two regions. The logarithmic temperature dependence is dominant from 1.5K to 35K and the square dependence from 50K to 340K. The logarithmic temperature dependence disappears after annealing (1/2 hour at 700K). The square dependence is characterized by the resistivity minimum at about 340K.
The transverse magnetoresistance effect decreases with increasing temperature and exhibits the minimum value near the compensation temperature. The electrical resistivity changes about 2.5% and the magnetoresistance effect about 0.01% over the range from 4.2K to 300K. This result shows that the number of domain walls makes very small contribution to the temperature dependence of

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Ribbon formed Alnico V alloy (23.7% Co, 14.4%Ni, 7.3%Al, 1.9% Cu, bal Fe) has been prepared by using a rapid quenching technique and their crystal structure, mechanical and magnetic properties have been examined. The results are summarized as follows:(1) The ribbon is 20-25 μm in thickness, about 1.5mm in width and 30-50cm in length and the surface of the ribbon shows metallic luster.(2) The crystal structure of the samples is b. c. c. structure with the lattice constant a₀=2.871±0.002Å. After annealing at various temperatures up to 1200°C, no change was observed.(3) The as-prepared sample can be wound around a rod of about 3mm in diameter and the value increases up to about 7mm after annealing above 600°C for 1h.(4) Annealing temperature dependence of coercive force shows two maxima at 830°C and 930°C. These temperatures are about 230°C and 60°C higher than those of cast Alnico V.(5) The effective temperature range of the magnetic field cooling is in the range between 875°C and 600°C. In addition to the magnetic field cooling, the sample was aged at 600°C for 20h. and H_c and (BH) _max increased up to 580 Oe and 4.1 MG·Oe, respectively.

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Ribbon formed Fe-Si-Al alloys (Fe: 81.5-96%, Si: 0-14%, Al: 4-17.5%) have been prepared by using a rapid quenching technique and their mechanical, magnetic and electrical properties and also crystal structure have been examined. The results are summarized as follows:(1) The ribbons are 15-30μm in thickness, 1-2mm in width and 3-5m in length and the surface of ribbons is metallic bright.(2) The crystal structure of Sendust alloys is b. c. c. and super-lattice of Fe₃Si (Al), while the crystal structure of Fe-Al-Si (Si<5%, Al<18%), Fe-Al and Fe-Si (Si<9%) alloys is b. c. c. structure.(3) The former can be wound around a rod of 3-5mm in diameter and the latter is very flexible and can be wound around a rod of 1mm in diameter.(4) Initial permeabilities measured at 1kHz for as-prepared Sendust ribbons are about 3×10³ and they increase up to about 2×10⁴ after annealing at 900°C for 1h.(5) Initial permeability takes a maximum at the same composition with that of bulk Sendust alloys where the lines of λs=0 and K₁=0 approach.(6) Electrical resistivity at the same composition is about 110μΩ·cm which is about 20% higher than that of bulk Sendust alloy.

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Attempts are made to prepare the cermet-type ferrite, which is a new magnetic composite material composed of ferrites and magnetic alloys. The main conclusions from the present study are as follows.
(1) Sendust alloy and ferrites have no affinity of make complexes.
(2) The measurements of saturation flux density show a large value of about 8, 000 G. or more for the composite materials which are composed of carbonyl iron of 60wt.% or more and magnetite.
(3) Addition of B₂O₃ causes an enhancement of density, saturation flux density and resistivity.

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The 44.7Cu-20.6Mn-34.7A1 (at%) alloy in the composition range between the Heusler phase and the κ phase exhibits a remarkable constricted hysteresis loop and high coercive force after tempering at about 300°C. The hysteresis loops at room temperature show diplacement along the H axis when the samples are cooled from 350°C to room temperature in the presence of a magnetic field. The displaced hysteresis loops are similar to those reported for mictomagnetic alloys and can be attributed to exchange anisotropy. The high coercive force and the displaced and constricted hysteresis loops observed in the alloy are explained to be caused by the exchange anisotropy interactions between ferromagnetic Heusler phase domains and antiferromagnetic Mn-rich phase domains.

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Sm-Co-Cu ternary alloy is a basic 2-17 type rare earth cobalt magnet with the highest energy product. The metallurgical behaviors and the phase constitution were investigated for Sm (Co_0.88Cu_0.12) _5.67 and Sm (Co_0.83Cu_0.17) _6.04. In the temperature range down to 600°C, they were confirmed to consist of two phases: 1-5 phase and 2-17 phase. Particularly, thermo-magnetic analysis is proved useful in estimating a variation in solubility of Cu in each phase. With decreasing temperature Cusolubility increases in 1-5 phase, while it decreases in 2-17 phase. Furthermore, coercivity was investigated for sintered magnet materials with the same composition in various stages of aging. During aging at 700°C, the coercivity reached the maximum of about 2 kOe after 32 hr of annealing, then decreased again. The cause of the magnetic hardening are discussed on the base of metallugical investigations, elucidating that it can be attributed to internal stress developed in 2-17 phase finely precipitated in 1-5 phase.

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The temperature dependence of magnetization and thermal expansion coefficient (α_cep) were measured for Fe-Pd alloys in the temperature range of 4.2K to 1100K. The magnetization at OK of fcc alloys quenched from 1420K increases with increasing Fe composition up to 70%Fe. The instability of ferromagnetism, such as an abrupt decrease of magnetization was not observed. The Invar anomaly the thermal expansion coefficient was observed in both the bcc and fcc regions. The anomaly of bcc phase is originated in an annealing effect. Using a Grüneisen relation for α_cep, an unharmonic term (α₁) of lattice vibrations was estimated for the fcc alloys. The anomalous part (α_a=α_exp-α₁) is negative in the whole temperature range and remains non-zero even above the Curie temperature. The magnetization and α_a can be well explained by the two-state model.
The low temperature transformation (fcc&harrfct, 0.28<x<0.335 at OK) was confirmed by the torque measurement. The X-ray Debye temperature (θ_M) of 34% Pd measured at low temperatures decreases with decreasing temperature. The decrease of θ_M associated with the lattice softening and the randam static displacement of atoms suggests the lattice instability of the Fe-Pd Invar.

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The structural and magnetic properties of Gd-Fe thin films prepared by ionized cluster beam (ICB) technique have been studied by means of Auger analysis, x-ray scattering and ferromagnetic resonance (FMR). Sample preparation was made by simultaneous deposion of Gd and Fe from each crucibles. To investigate the influence of ion on the structure and magnetic properties of films, only Fe clusters were ionized. From Auger analysis, films were found to be uniform over a large surface area (about 5×5cm²). Caluculated reduced density functions G (γ) indicate that Gd-Fe pair is dominant even when 30% of Fe clusters are included. Furthermore, the density of Fe-Fe pairs is fairly small even when neutral clusters alone were deposited, which probably due to the large surface diffusion enegy of neutral clusters with kinetic energy of 120eV corresponding to their ejection speed. The peak around 5 Å in G (γ), which indicates the multiple coupling of Fe atoms, reduces to zero together with the Gd/Fe ratio equal to 1. Spin waves were observed in the perpendicular FMR spectrum. The caluculated gand A values of the film were determined to be 1.67 and 0.35 × 10^-6erg/cm, respectively.

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Stripe domains parallel to the incident vapour axis are characteristic to oblique incidence films of grazing angles. The mean magnetization of the domain has a dominant in-plane component parallel to the incident axis and a minor perpendicular component.
It is common to the stripe domains in the Fe-Ni and Fe-Co alloy films examined that there exist both in-plane and perpendicular magnetization ripples with different wave lengths, the minimum of which is about 2-300 Å, which is due to distribution of the easy axis of the shape anisotropy of columnar grains. Long range ripples extend crossing numbers of stripe domains and have structural correlation with the wall structure.
The domain walls of the stripe domains consist of Bloch and Néel type wall fragments with different signs alternately arranged along the wall.
Columnar grains composed of several crystalline grains influence exchange interaction and magnetostatic interaction of the spin system, which explains the domain structure qualitatively.

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This paper proposes a multi-partitioned chip for a dual-conductor bubble memory and describes its characteristics. By use of n-1 parallel slots (n; the number of partitions), the conducting sheet of the chip is cut into a meandering strip. So the current required for bubble propagation decreases to 1/n and the chip resistance increases by a factor of n², as confirmed by experiments on large-scale models. The chip can be matched to the drive circuitries by selecting the partition number n. As the slots also divide a minor loop into the smaller ones, a true swap gate is essential to the chip. Two types of true swap gates as well as a block-replicate gate are proposed in this paper. The operations of these gates are discussed using the results measured on scale-up models. The chip organization is changed by a gate control method, e. g. when the swap gates, classified according to the parity of slot number, are controlled independently, minor loops are equivalent to bubble ladders. So the multi-partitioned chip can be adapted to various applications.

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Changes in magnetic anisotropy and lattice strain induced by He⁺ ion implantation were compared for various garnet compositions. Among them, three drive layer compositions (GdSmTmCaGe, GdSmYbCaGe and YEuLuCaGe) were chosen in order to investigate the effects of ion implantabilities on bubble propagation margins in double layered contiguous disk devices. Bubble supporting layers used in the present experiments were visually observable YSmLuBiCaGe garnets (h-2μm, l=0.18μm and φ_F=-2000°/cm). Bubble propagation margins around an isolated circular pattern and a contiguous disk loop (8μm period) were both measured and discussed in terms of H_K1, _Kσ and asgrown Q of the drive layer materials. Suitable H_K1, is approximately 50 Oe, because a too high H_K1, value causes larger H_rmin due to delay in charged wall position with respect to direction of in-plane field. Charged wall becomes unstable at higher H_γ, when K_σ is small. When Q value of as-grown drive layer reaches 1, magnetic poles are found to generate under masked patterns due to large strain outside the patterns, thus bringing about margin degradation at higher H_γ.

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Contiguous disk (CD) bubble propagation track without ion-implantation has been developed, where a YIG layer is grown on a bubble supporting layer with ion-etched CD patterns by chemical vapor deposition (CVD). Ion-ethced film thickness difference at pattern boundary is necessary to hold bubbles at the CD pattern edges by the edge affinity and the bias potential barrier. From the bubble position dependence on a rotating in-plane field H_γ, phase angle and the domain observation by ferrofluid, magnetic poles induced by H_γ at the pattern edges are found to be effective to propagate the bubble domain. Magnetic poles, induced in the part of the tapered YIG region surrounding the pattern edges, assist the bubble propagation stability, by shifting the minimum potential well position due to magnetic poles in the YIG layer on CD patterns to an edge affinity minimum potential well position. The positive magnetic poles at the YIG layer edge outside CD patterns partly compensate negative magnetic poles induced in YIG pattern at the pattern cusp, keeping bubbles from collapsing. Consequently, bubble propagation margins, greater than about 10%, are obtained in 2μm bubble films.

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The operation of a magnetic bubble domain straight-line propagate circuit has been simulated successfully by using a numerical scheme developed previously to simulate the motion of a magnetic bubble with its domain shape and the magnetization structure along its domain wall left variable in the course of simulation. To examine the feasibility of the computer simulation of the device operation, the drive field of the propagate circuit has been given analytically by H_z (X, Y, T) =-H_p cos [2π(X/R_x-n(T)/4)] exp [-(Y/R_y)²] after dual-conductor-sheet current-access devices. A method of testing bubble propagation with minimum length of the simulation time lapse has been established. Margin diagrams in terms of the drive amplitude H_p and dc bias field have been obtained for bit period R_xof 8, 10 and 12μm at 1 MHz drive. The program is fast enough for the simulation of actual current-access devices to be performed in a practical CPU time, provided the drive field is given. The outline of the entire simulation program and salient simulation results are given.

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Using the Finite Element Method (FEM), an investigation has been made to obtain the relations between the reproduced output of a magnetoresistive (MR) head and its dimensions and magnetic characteristics. The FEM process includes the calculation procedures for the magnetic saturation and residual magnetization.
The following results by this analysis have been obtained: 1) The reproduced output increases as the magnetic permeability of the MR thin film increases. 2) The equation for the spacing loss of a vertical MR head is similar to that of a conventional ring head. 3) The reproduced output increases as the stripe width of a MR head decreases. 4) The shield layers for a MR head are not effective to increase reproduced output.

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The thermomagnetic writing was studied for (BiSmEr) ₃ (GaFe) ₅O₁₂ films. Since the optical absorption coefficient (α) of this kind of films is relatively low, the writing threshold power (P_w) becomes larger than those of other materials.
In order to lower P_w, the effective optical-path length was enhanced by increasing the film thickness (h) and/or by coating them with reflecting layers. Firstly, P_w was minimized by choosing h=1/α to 2/α; i. e. P_w=20mW at h=2.2μm, 13 mW at 2.2μm and 12 mW at 1.0μm, for the laser irradiation with the duration of 10μs, a spot radius of 2.5μm, and with λ=514.5, 488.0 and 457.9 nm, respectively. Analytical calculation of heat conduction for this system indicates that the optimum thickness for which the temperature elevation on the film-substrate boundary reaches maximum lies also between 1/α and 2/α. Since, however, the selection of the film thickness is limited by restriction in the wall coercivity (H_w), some reflecting layers were put on these films. The preliminary results for a 0.55μm thick film with a 0.12 μm thick Al reflector are P_w=26mW for λ=514.5nm, and 20 mW for 488.0 nm. These values of P_w were 52% and 69% of those without reflector, respectively.

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One of the most important properties of a perpendicular magnetic recording will be the magnetic interaction between the head pole and the recording medium. Especially, in a double-layered medjum consisting of a perpendicularly anisotropic layer and a high permeability layer, the recording sensitivity is assumed to be greatly increased by the effects of this interaction. The mechanism of the interaction is not well understood, but the interaction is clearly crucial to the realization of an effective recording.
This paper proposes two models for the interaction between the head pole and the double-layered medium and analyzes the mechanism of this magnetic interaction. The analysis gives the following results:(1) The interaction between the head pole and the double-layered medium is very strong as compared with that between the head pole and a single layer medium having a perpendicularly anisotropic layer alone, because the magnetization in the high permeability layer strongly interacts with that in the perpendicularly anisotropic layer.(2) Considering a medium in which the high permeability layer substituted for the prependicularly anisotropic layer of double-layered medium, the magnetic interaction between this medium and head pole almost coincides with that between the double-layered medium and the head pole.

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A new preparation method for γ-Fe₂O₃ thin film recording media has been established.
Using sintered Fe₃O₄ plates as targets, magnetic film are directly formed through ordinary r. f. sputtering in argon atmosphere. Those as-sputtered film compositions were examined and confirmed to be Fe₃O₄, which were formed over wide sputtering condition range.
In order to realize high-rate sputtering, planar magnetron r. f. sputtering was attempted. Sputtering rates several times higher than those for ordinary sputtering were obtained. A rate as high as 2, 000 Å/min was attained at high power densities. These as-sputtered films were also confirmed to be Fe₃O₄ and formed over wide ranges of argon pressure 2×10^-3-5×10^-2 Torr, substrate temperature; R. T.-300°C, and target-substrate distance 2-4cm. Thus, the present method assures high productivity and reproducibility.
Effects of other elements doping have been investigated to improve Fe₃O₄ film properties. As doping elements, cobalt and copper were chosen. Copper promoted oxidation from Fe₃O₄ to γ-Fe₂O₃. It was revealed that γ-Fe₂O₃ films (ρ=1×10³Ω·cm) on anodized aluminum alloy substrates, obtained by high-rate sputtering of 2% Co, 2% Cu doped Fe₃O₄ target, had magnetic characteristics suitable for high recording densities.

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MnAl and MnAlCu magnetic films were prepared by vacuum evaporation. Magnetic properties of the evaporated films were investigated with attention to the development of magnetic recording media. The conditions of fabrication of films having maximum coercivity and squareness ratio were as follows: the substrate temperature, ca. 400°C, the deposition rate, 120Å/sec, and the concentration of Mn 75 wt.%. Magnetic properties of MnAl films prepared under these conditions were 1.3 kOe in coercivity, 0.65 in squareness ratio, 150 gauss in saturation induction.
Addition of a few wt.% of Cu had an effect of increasing saturation induction, while the coercivity was found to decrease with the addition of Cu. MnAlCu evaporated films showed the coercivity of 660 Oe, the squareness ratio of 0.6 and the saturation induction of 320 gauss.

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Effects of hysteresis loop shape on recording density characteristics have been examined for particulate coated disk media. High-density recording characteristics have been evaluated with experiments and computer simulations. Potter and Schmulian's method is applied to computer simulations, except that media M-H loop formulation is modified to get better fits to measured loops. Following results were obtained. For media with 0.76 to 0.81 squarenesses S (≡B_r/B_s), the difference in coercive squareness S* ranging 0.67 to 0.72 gives no significant effects on their recording density characteristics. However, in case of remarkably different 2nd quadrant M-H loop media, for example 0.72S, 0.78S* and 0.81S, 0.65S*, the former larger S* media is superior to the latter higher S media.

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The spin reorientation phase transition in DyFeO₃ (T_r-42 K) was studied by the observation of magnetic domains. The magnetic phase diagram was obtained through the measurements of nucleation field H_n and saturation field H_s for the field-induced spin reorientation between P₁ and P₄ at various temperatures below T_r. The coexistence of P₁ and P₄ phases in the fields between H_n and H_s shows that the transition is of a 1st order. The anisotropy constant of Fe³⁺ spins between the a-axis and the b-axis was determined as 2K_ab -0.029 K (-7.2×10⁴ erg/cm³) from the analysis of the phase diagram. An extraordinary pattern was observed in the ab-plane at T<T_r when the applied field along the c-axis was increased up to slightly below H_n. It was suggested that the P₁₄ phase of Fe³⁺ in the presence of magnetic field was responsible for the pattern.

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An optically induced magnetization of ruby is observed at room temperature by selectively exciting Cr³⁺ ions with a right-and a left circularly polarized light of a Q-switched ruby laser from one of the ground ⁴A₂ multiplets to a proper component of the upper E (²E) multiplets. Dependence of such a magnetization in the Z (C₃)-direction of the Cr³⁺ concentration and the ellipticity was measured with a pick-up coil. The relaxation time of the ground state in a 3wt% ruby was estimated from the decay to be about 55ns in zero magnetic field. The induced magnetization of a 1.6% ruby is about 9 times as large as that in a 0.05% ruby. A new function element using the conversion property from a light to a magnetic field is proposed.

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This paper proposes a new frequency modulator using a ferrite orthogonal core and its application to thyrystor parallel inverter.
The expressions for the output oscillation frequency and for the relation between primary and secondary flux are derived.
A new thrystor parallel inverter has many excellent characteristics as speed control device of induction motor, which include simplicity of circuit construction, good isolation between gate circuit and thyrystor main circuit, wide variable frequency range and noise absorption characteristics.

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A detailed study on the flux resetting characteristics of amorphous toroidal cores was made from low to the high frequency range. The instrument for measuring Control Magnetization Curve (CMC) covering the high frequency range was constructed. The microscopic fluctuation in the flux resetting characteristics decreases with increasing the exciting frequency in the case of Fe₅Co₇₀Si₁₅B₁₀ which has rectangular hysteresis loop. In a wide range of the exciting frequency the value of the full-reset force which is obtained from CMC agrees well with that of the coercive force which is obtained under sinusoidal flux condition. It indicates that the iron loss of the cores will be estimated from CMC. The gain of the amplifier using amorphous core which is driven under minor dynamic hysteresis loop becomes higher as the exciting frequency increases. From these results amorphous cores are expected to be applied to the devices which acts in the high frequency range.

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The heating characteristics of electromagnetic cooker are analyzed by using the finite element method in such a way that the reaction fields due to eddy currents are taken into account. The effects of the construction of magnetic circuit, exciting frequency, and thickness and material of heating metal are investigated.
The obtained results can be summarized as follows:
(a) The heat generation does not so increase with the exciting frequency, when the frequency is larger than 7 kHz.
(b) The heat generation becomes the maximum at certain thickness of heater.
(c) Compound metal heater is effective under the excitation of commercial frequency.
The calculated results are in good agreement with the experimental ones. These results give useful suggestions improving the design of electromagnetic cooker.

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Extremely sensitive stress-magnetic effects in iron-rich amorphous ribbons which are partially crystallized by the heat treatment at the temperature between Curie and crystallization temperatures are presented, and its application to senstitive shock-stress sensors is also described.
Iron-rich amorphous magnetostrictive ribbons which have sensitive and linear stress-magnetic characteristics, high flux desnity, high permeability, low losses, and outstanding elasticity are suitable for applications to force and displacement transducers. This stress-magnetic effects are dramatically improved by using the micro-crystallization technique which is estimated by X-ray diffraction methods. That is, for example, when a Metglas 2605 ribbon is annealed at the temperature of about 350°C, 60 min., the variation of the maximum permeability Δμ_m/μ_m0, for a 60Hz field with optimal amplitude reaches to about 15 (1500%) in saturation value against the tensile stress applied to the ribbon axis. Micro-crystallization which induces the easy axis of magnetization in the ribbon-width direction is also realized by rapid heating followed by quenching, in which the maximum tensile strength of the ribbon is more than 110kg/mm².
A new very sensitive shock-stress sensor with no power is constructed by inserting the anomalously stress sensitive ribbon into a coil and by fixing to an alminium box. Transient oscillating voltage waves are observed at the coil terminals after a drop of a small needle of 20mg from 1-cm height.

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