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Volume 57, Issue 8
Displaying 1-19 of 19 articles from this issue
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Kiyoshi Watanabe, Makoto Nakazawa1993 Volume 57 Issue 8 Pages 853-857
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSCrystal structures and magnetic properities of Ir-Mn-Sn alloys have been investigated by means of X-ray diffraction and magnetic analysis. It has been found that a new L21-type intermetallic compound (Heusler alloy) of Ir1.8Mn1.2Sn exists in the Ir-Mn-Sn system and forms a solid solution in a wide composition range, where Ir1.8Mn1.2Sn to Ir1.6Mn1.4Sn have lattice parameters of 0.6204 to 0.6189 nm, magnetic moments of 3.2 to 2.6 μB/Mn and Curie temperatures of 342 to 265 K. The typical Ir1.8Mn1.2Sn compound has a lattice parameter of 0.6204 nm, a magnetic moment of 3.38 μB/Mn at absolute zero Kelvin and a Curie temperature of 342 K. The magnetization and Curie temperature of their alloys decrease with decreasing lattice parameters, which depend on Mn-Mn interatomic distance remakably.
The solid solution of the C1-type has been obtained near the composition of equi-atomic ratio, but their alloys have not characteristic values of the ferromagnetic C1-type compounds.View full abstractDownload PDF (481K) -
Hideshi Nakatsu, Setsuo Takaki, Youichi Tokunaga1993 Volume 57 Issue 8 Pages 858-863
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe effect of austenite (γ) grain size on the formation process and morphology of ε martensite (ε) has been investigated by means of optical microscopy, transmission electron microscopy and X-ray analysis in an Fe-15 mass%Mn alloy, whose austenite grain size was controlled between 1 and 130 μm by the reversion treatment from deformation induced bcc martensite to γ. With grain refining, the formation of ε tends to be suppressed and the starting temperature of γ→ε transformation (Msγ→ε) is also lowered. In the grain size region below 30 μm, these phenomena are more significant. In the case of fine austenite grains, ε plates are formed accross a small γ grain from one boundary to the other. When the size of the γ grain is above 30 μm, the microstructure change to a different one in which a lot of ε plates intersect each other within a large γ grain. In this case, ε plates are formed on four {111}γ planes in the Shoji-Nishiyama relationship. The formation process of ε plates in a large γ grain is as follows. When one ε plate grows to some critical size, branching occurs at a tip of the ε plate in order to reduce the elastic stress at the γ⁄ε interface, and ε plates with different variants are formed one by one on different {111}γ planes. When the γ grain size is small enough in comparison with the critical ε plate size, the γ phase is stabilized because such a chain reaction in the ε transformation is suppressed owing to grain boundaries.View full abstractDownload PDF (1599K) -
Hideki Hagi1993 Volume 57 Issue 8 Pages 864-869
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSDiffusion coefficients of hydrogen in 0∼0.6 mass% carbon steels with spheroidized cementite-ferrite and pearlite-ferrite structures have been measured by the electrochemical permeation method at 278∼318 K. The temperature and carbon concentration dependence of the diffusion coefficients has been discussed by using a simple trapping model. The diffusivity of hydrogen is lowered with increasing carbon concentration and depends on the specimen structure. This is caused by the trapping effects of cementite-ferrite interfaces and dislocations. The binding energy between the cementite-ferrite interface and a hydrogen atom is slightly less for the planar cementite than that for the spherical cementite.View full abstractDownload PDF (573K) -
Satoshi Ishikawa, Shigeru Asano1993 Volume 57 Issue 8 Pages 870-875
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSHydrogen-induced phase transformation was studied on Fe-Cr-Mn alloys composed of the single (γ) phase, the dual (γ+ε) phase and the ternary (γ+ε+α) phase. In all the alloys, a new HCP structure was observed after cathodic hydrogen charging, which corresponds to the εH phase in austenitic stainless steel. The εH phase of the single-phase alloys seems to be transformed from the γ matrix, whereas the εH phase of the dual-phase and ternary-phase alloys is considered to be separated from the pre-existing ε phase.
In manganese-rich alloys composed of single phase (γ), a hydrogen peak of internal friction was detected after cathodic hydrogen charging. This hydrogen peak seems to be attributed to a Snoek-type relaxation caused by hydrogen diffusion in the γ matrix, as has been proposed for austenitic stainless steel and Fe-Ni alloy. Its relaxation strength decreased considerably with the content of manganese in these alloys at almost the same hydrogen concentration.View full abstractDownload PDF (687K) -
Kenji Matsuki, Hiroaki Matsumoto, Mitsugu Tokizawa, Norio Takatsuji, M ...1993 Volume 57 Issue 8 Pages 876-883
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe effect of SiC particulate volume fraction on hot deformation of a mechanically alloyed 7075Al alloy (MA7075) and three 7075Al alloy composites reinforced with SiC particulate (MA7075+5SiC, +10SiC, +15SiC composites) has been studied by the compression test. The samples were compressed to about 65% at a temperature of 793 K and in an initial strain rate range from 10−3 s−1 to 2×10 s−1.
The strain rate sensitivity exponent m was larger than 0.33 at high strain rates (Region 2) and, in contrast, less than 0.13 at low strain rates (Region 1). Grain boundary sliding occurred more remarkably in Region 2. With increasing of the SiC particulate content, the transition in strain rate between Region 1 and Region 2 moved to be higher, and the compressive stress increased in the whole strain rate range. The increase in flow stress was more remarkably in Region 1.
Threshold stresses (σth) for each composites increased with increasing of the SiC particulate content. A double logarithmic plot of strain rate and effective stress, σe, (=σ−σth) can be approximated by a straight line with a slope of 0.5 irrespective of Regions 1 and 2 for MA7075+SiC composites. This strain rate sensitivity exponent of 0.5 is explained by the value predicted from the grain boundary sliding model accommodated by dislocation slip.
It was suggested that the presence of SiC particulates on grain boundaries seemed to resist the grain boundary sliding, thus resulting the threshold stress. The transition from region 1 to region 2 was considered to be not necessarily reflect the change in deformation process but to be arose from the effect of the threshold stress on the superplastic model with grain boundary sliding descrived above.View full abstractDownload PDF (2032K) -
Hiroshi Haji, Toshiaki Morita, Hideharu Nakashima, Hideo Yoshinaga1993 Volume 57 Issue 8 Pages 884-889
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn order to investigate the effect of ultrasonic vibration on wire bonding, an apparatus which enabled compression tests under ultrasonic vibration in a wide range of frequency and amplitude was developed. High purity gold, aluminum and copper specimens were used for the compression test. The apparatus was applied also to the practical wire bonding. The results obtained are as follows.
(1) The flow stress is reduced by superimposing the ultrasonic vibration. The stress reduction increases with the increase in frequency and amplitude.
(2) The shear strength of wire-bonded interface increases also with the increase in frequency and amplitude.
From these results, the effects of ultrasonic vibration on wire bonding are discussed.View full abstractDownload PDF (503K) -
Takashi Motoyoshi, Hiroyuki Sato, Hiroshi Oikawa1993 Volume 57 Issue 8 Pages 890-897
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe effects of nitrogen on the creep characteristics of substitutional alpha solid solutions, the Fe-W and Fe-Mo systems, have been investigated at 1100 K. Three stress regions in the power-law creep regime are observed in these solid solutions, except the Fe-Mo-N solid solution. In Region L, nitrogen strengthens the Fe-W solid solution, while it weakens the Fe-Mo solid solution. The effect of nitrogen on the creep strength of the Fe-W solid solution is negligibly small in Regions M and H. In the Fe-Mo solid solution, however, the transition stress between Regions M and H increases with the addition of nitrogen and the steady-state creep-rate decreases in Region H.
The effects of nitrogen on the creep characteristics depend on the substitutional solute in these solid solutions. The difference in the effects of nitrogen can be attributed to the difference in the interaction between interstitial and substitutional elements. In the Fe-Mo solid solution, nitrogen interacts strongly with molybdenum and so-called “IS effect” causes the increase of transition stress between Regions M and H in this system. In contrast, the interaction between nitrogen and tungsten is weaker than that of nitrogen and molybdenum, so that little changes in the transition stress are observed in the Fe-W solid solution.
It becomes obvious that the addition of interstitial elements affects creep characteristics in the temperature range above 0.5 Tm (Tm: melting point), but accumulation of experimental results and detailed considerations are needed to understand the rate-controlling mechanism in Region L.View full abstractDownload PDF (800K) -
Kenki Hashimoto, Minoru Nobuki, Haruo Doi, Takashi Kimura, Tokuzou Tsu ...1993 Volume 57 Issue 8 Pages 898-904
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSAfter the heat-treatment of 1473 K-10.8 ks, the yield stress of TiAl(γ) base alloys, Ti-50 mol%Al, Ti-(50-C)mol%Al-C mol%X, and Al-(50-C)mol%Ti-C mol%X, was examined by the compression test as a function of temperature (295-1273 K) and the amount, C(0.5∼2.0), of third elements, X(Cr, Ga, Zr, Nb, Sb, Hf, Pd, Pt, Ta). Micro-hardnesses of γ in the alloys were measured at room temperature to confirm solid solution hardening. The microstructures were examined using OM, SEM, EPMA and XRD. The results obtained were examined with regression analysis and compared with the microstructures.
The micro-hardness increased with the amount of additives. The increase was remarkable with increasing difference in atomic radius between Ti or Al and X atoms. In the temperature range of 295-1073 K, the yield stress is in proportion to the micro-hardness and influenced by the amount of Ti3Al phase and the grain size of γ phase. At 1273 K, the effect of the microstructure on the yield stress decreased and the effect of solid solution hardening become prominent.View full abstractDownload PDF (2018K) -
Hiroyuki Fukuyama, Jun Shimotori, Toshiharu Fujisawa, Chikabumi Yamauc ...1993 Volume 57 Issue 8 Pages 905-913
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn view of the application of sodium carbonate slag to the elimination of Sn from molten copper, the thermodynamic properties of NaO0.5-CO2-SnO2 slag have been studied by conducting the following experiments:
(1) Activities of NaO0.5 in the slag were determined by the EMF method using β′′-alumina as a solid electrolyte over the composition range of 1>N≥0.795{N=nNa+(nNa⁄nSn),n:the number of moles}under the partial pressures of CO2 of 0.001∼0.08 MPa at 1423∼1523 K. It was found that the activity of NaO0.5 did not depend on the slag composition for the constant partial pressure of CO2 and the slag was saturated with Na2SnO3(s).
(2) Then the solubility of Na2SnO3(s) into the sodium carbonate melt was measured under the various partial pressures of CO2 at 1523 K. With decreasing the partial pressure of CO2 the solubility increased, but the partial pressure of oxygen had no effect.
(3) Activities of SnO2 were determined by the distribution equilibrium measurements for Sn between the Na2SnO3(s)-saturated slag and molten copper. From the activity of SnO2 combined with that of NaO0.5, the standard free energy change for the following reaction was determined as:
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\ oindentThe activity of SnO2 in the homogeneous liquid region of the slag was also evaluated by the distribution equilibrium measurements.
Based on the results obtained, the distribution ratios of Sn between the slag and molten copper were estimated. The ratios decrease with decreasing SnO2 content in the Na2SnO3(s)-saturated slag. The higher oxygen partial pressure and the lower CO2 partial pressure are more preferable for the removal of Sn from molten copper.View full abstractDownload PDF (784K) -
Naoki Washizu, Yuji Ikeda, Hiroyuki Masuda1993 Volume 57 Issue 8 Pages 914-918
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe amount of Photoelectron Emission (PEE) depends upon the quantum efficiency of materials. The measurement of PEE, therefore, can be applied to analyze the surface of materials. In this work, it was applied to the study of initial oxidation at high temperature. PEE was measured on several materials such as pure metals: Fe and Cr, oxides: FeO, Fe3O4, Fe2O3 and Cr2O3. The PEE intensity was ten times larger on Fe2O3 (36 pA) than the other materials. Fe, Cr and Fe-Cr alloys were oxidized at 900∼1000 K in air up to 1.8 ks. As the oxidation progressed, the intensity of PEE changed in different manners when materials varied. The PEE from Fe increased until it reached the saturation at 35 pA (that is a value observed on Fe2O3), while that from Cr remained constant at 4 pA. The PEE from the Fe-Cr alloys reached a similar value to Cr after passing through a maximum. Auger electron spectroscopy showed that the surface concentration of Fe on the Fe-Cr alloys varied in a similar manner to the change of PEE. Thus it is concluded that the amount of PEE reflects the quantity of Fe2O3 at the surface and therefore allows to follow the initial oxidation process.View full abstractDownload PDF (385K) -
Tsutomu Ikeda, Hiroshi Satoh1993 Volume 57 Issue 8 Pages 919-925
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSAn extensive study was carried out on the phase relations, microhardness and oxidation properties of hard coatings formed in the Ti-Al-N system using the cathodic arc ion plating method. When the ratio of the partial pressure of N2 to the evaporation rate of titanium was reduced, the resulting phases in the Ti-N system changed from cubic TiN through tetragonal Ti2N to h.c.p. α-Ti. When the AlN content in the TiN-AlN solid solution was increased, the films, from TiN up to (Ti0.3Al0.7)N, exhibited a cubic B1 structure. As the AlN content increased, the lattice parameter monotonically decreased from 0.426 nm for TiN, to 0.416 nm for (Ti0.3Al0.7)N. With a further increase in the AlN content, (Ti0.15Al0.85)N films were found to have a wurtzite structure. It was concluded that the crystal structure of the ternary Ti-Al-N system along with the wide-ranging solubility of AlN in TiN is typical for the isostructural group of cubic titanium-based nitrides. The (Ti1−xAlx)N films with a cubic structure were stable in air at the temperatures ranging from 710°C for x=0.25 to 830°C for x=0.6, whereas the TiN films began to oxidize at 550°C. It was found that protective layers of aluminum oxides formed on top of the (Ti, Al)N films during elevated temperature oxidation tests protected the films from further oxidation. The crystallized TiO2 that was formed on the TiN film did not give the same protection. Tool-life tests on the (Ti, Al)N coated carbide inserts revealed the superior wear resistance, compared with a variety of nitride-coatings including TiN.View full abstractDownload PDF (774K) -
Yukio Ide, Takashi Nakamura1993 Volume 57 Issue 8 Pages 926-931
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIt is very useful to be able to practically monitor the plasma on the synthesis of titanium nitrides by an activated reactive evaporation (ARE) method using optical emission spectroscopy. Since each of emission lines from titanium and nitrogen could be detected without interference, the relationship between the intensities of the emission lines and the important operating parameters of ARE such as applied probe voltage, EB emission current and nitrogen partial pressure were investigated in the present paper. The results were summarized as follows.
(1) Both of the titanium and nitrogen emission intensities were proportional to the applied probe voltage.
(2) The titanium emission intensity increased with increasing EB emission current with or without nitrogen.
(3) The nitrogen emission intensity increased with increasing partial pressure, but the titanium emission intensity decreased.
(4) It was found that the N/Ti atomic ratios of titanium nitride films analysed by EPMA were slightly correlated to the N/Ti emission intensity ratios of the plasma monitored.View full abstractDownload PDF (459K) -
Minoru Sueda, Toshiro Kobayashi, Tadashi Rokkaku, Yasuhiro Fukaya, Tet ...1993 Volume 57 Issue 8 Pages 932-937
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSCubic boron nitride (cBN) has many excellent properties, such as the highest hardness next to diamond, high electrical insulation and high thermal conductivity. cBN films were deposited by IVD (Ion-beam-assisted vapor deposition) method. Effects of the ion current density, the composition of the supplied gas into the ion source and pressure in the vacuum chamber on cBN formation were investigated. At a constant B deposition rate, cBN was formed in a certain range of an ion current density. XPS analyses showed that the cBN film has a stoichiometric composition of BN, and the diffraction patterns from cBN (111), (220) and (311) were observed by transmission electron diffraction. Under the constant ion acceleration voltage and the B deposition rate (0.5 kV, 0.13 nm s−1), cBN was formed when an Ar-based gas containing N2 of 20 to 80% was supplied to the ion source. The deposition rate of cBN films was as high as about 5×10−2 nm s−1 and the range of the cBN formation conditions was wide when the Ar-based gas contained N2 of 36 to 50%. With increase of the pressure in the vacuum chamber, cBN formations were observed at lower ion current densities. We consider that this is due to the charge exchange and not only ions but accelerated fast neutrals also contribute to the cBN formation. Based on the above results, we propose a map of the cBN formation conditions as functions of fast N2 flux and fast Ar flux.View full abstractDownload PDF (831K) -
Masanobu Ohmori, Kohshi Tanimoto, Motohisa Yoshida, Fusahito Yoshida, ...1993 Volume 57 Issue 8 Pages 938-943
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSSmall cylindrical billets (φ10 mm×15 mm) taken from a cast chromium ingot and a sintered powder chromium one were isothermally extruded at warm temperatures of 573 to 693 K using dies with extrusion ratios of 2.0, 2.8, 4.0 and 6.3. The present findings are summarized as follows.
(1) The workability for both chromiums was poorer in the extrusion of the higher punch speed, lower temperature and smaller extrusion ratio. The circumferential cracks occurred on the surface of the chromium extruded in a poor working condition were supposed to be due to the axial tensile stress appeared in the outer layer of the chromium passing through the final stage of die.
(2) The extrusion workability of the cast chromium with very large crystal grains was much smaller than that of the sintered powder chromium with fine grains.
(3) The poor workability of the cast chromium could be improved by reducing its large grain size to a finer one by means of an upsetting-annealing operation. The improvement of the workabillity is considered to be brought about through the increased fracture strength which originated from the reduced grain size.View full abstractDownload PDF (1041K) -
Yuji Muramatsu, Tsuneo Ohkoshi, Hiroo Suga1993 Volume 57 Issue 8 Pages 944-951
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn order to develop highly densified TiAl by die compaction-sintering method, the sintering behavior of Ti(or TiH2)+TiAl3 mixed powders, promising as a starting powder, was investigated.
The mixed powders were consolidated by cold pressing and sintered in vacuum without extermal pressure. In the sintering behavior, the densification characteristics of mixed powders were examined as a function of particle size and composition, and the microstructure and oxygen content of the sintered TiAl were also examined.
The results were as follows:
(1) The densification behavior of the Ti+TiAl3 mixed powders was influenced by the particle size of constituent powders, especially the size of Ti powder. With refining Ti powder, a greater densification over 95% relative density took place.
(2) The densification behavior of the mixed powders was also inflienced by their composition. Although Al-rich TiAl of 55 at%Al showed a small densification irrespective of a proper adjustment of particle size, TiAl containing 40∼50 at%Al showed excellent sinterability. This is mainly due to the α-Ti phase which appears during sintering.
(3) The microstructure of sintered TiAl of 55 at%Al consisted of a single γ-phase, while those of 40∼50 at%Al were composed of equiaxis γ-phase and γ⁄α2-lamellar structure. In the mixed structures, the amount of the lamellar structure increased with a rise of sintering temperature and decreased with an increase of Al content.
(4) The oxygen content of sintered TiAl was dependent on the oxygen content of starting powders, de-waxing conditions, the amount of interconnected pores and so forth. It was found that the oxygen content of the highly densified TiAl obtained by this die compaction-sintering method was 0.45∼0.55% and an appropriate handling of starting powders made it possible to reduce them less than 0.4%.View full abstractDownload PDF (1228K) -
Yong-Ho Park, Hitoshi Hashimoto, Mamoru Nakamura, Toshihiko Abe, Ryuzo ...1993 Volume 57 Issue 8 Pages 952-956
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSA powder premix of Ti and B (Ti:B=1:2) was vibratory ball milled with steel balls of six sizes ranging from φ4.76 to φ25.4 mm, at powder/ball weight ratios ranging from 1/50 to 1/200, to investigate the effects of milling ball size and powder/ball weight ratio on the formation of Ti-B compound during milling. The formation process was studied by X-ray diffraction analysis and SEM observation of the milled powders. During milling, the temperature of the milling container was measured by a thermocouple attached to the side-surface of the container. The phase of the milled powders in general changed from the mixture of the elementary Ti and B to an amorphous phase and then to a crystalline compound phase. This sequence of the phase change is similar to that in the phase change process of combustion synthesis proposed by Merzhanov. An exothermic temperature spike was observed during milling when milled with steel balls of the size of φ19.1 mm or more. During this temperature increase, the amorphous phase rapidly changed into the crystalline compound phase and fine particles in a size range from several tens to several hundreds of nanometers were formed. On the other hand, no temperature spike was observed when milled with balls of the size of φ17.5 mm or less. The phase change from amorphous to crystalline and the formation of the fine particles occurred gradually. Both the ball size and the powder/ball weight ratio affected the exothermic behavior, the milling time required to start the temperature spike and the magnitude of the temperature increase.View full abstractDownload PDF (939K) -
Ken-ichi Kakimoto, Toshio Shimoo, Kiyohito Okamura1993 Volume 57 Issue 8 Pages 957-963
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe pyrolysis of Si-Ti-C-O amorphous fibers (Tyranno fiber) coated with oxide layers of various thicknesses was investigated in an argon stream at 1673 K. Oxide layers were formed on the surface of the fiber in an oxygen stream at 1673 K. The thicknesses of the oxide layers were 0.12, 0.21, 0.42 and 0.65 μm. The fibers with the oxide layers of various thicknesses were heated rapidly and kept in an argon stream at 1673 K. During this heat treatment, the mass change of the coated fibers was measured continuously with a thermobalance. The heat-treated fibers were examined with X-ray diffraction, AES, SEM and TEM observation.
The fiber with oxide layer of 0.12 μm thickness pyrolyzed completely, and the growth and coarsening of the β-SiC crystal were observed. The pyrolysis of the fibers with oxide layers 0.21, 0.42 and 0.56 μm in thickness was inhibited significantly. The degree of crystallization to β-SiC in the inner area of the fiber increased as the thickness of the oxide layer increased. The oxide layer of the fiber was removed by chemical etching treatment, and it was prepared in order to measure its tensile strengh. The tensile strength of the fiber was inversely proportional to the size of β-SiC crystallite. The tensile strength of the fiber with the oxide layer of 0.21 μm thickness was 58% as large as that of the original fiber.
If the Tyranno fiber is coated with an oxide layer of more than 0.21 μm thickness, the high-temperature strength of the fiber can be improved fairly.View full abstractDownload PDF (2407K) -
Kiyonori Suzuki, Akihiro Makino, Akihisa Inoue, Tsuyoshi Masumoto1993 Volume 57 Issue 8 Pages 964-971
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSA mostly single bcc phase with a grain size of about 15 nm was obtained by annealing amorphous Fe-Hf-B alloys ranging from 5 to 7 at%Hf and 1 to 8 at%B for 3.6 ks at temperatures between 773 and 923 K. High effective permeability (μe) above 10000 at 1 kHz and high saturation magnetization (Bs) above 1.5 T were simultaneously obtained for the nanocrystalline-bcc alloys. μe and Bs reach 15000 and 1.65 T, respectively for Fe91Hf7B2 and 32000 and 1.59 T, respectively for Fe89Hf7B4. Saturation magnetostriction (λs) was as small as −1×10−6 for the nanocrystalline-bcc Fe89Hf7B4 alloy. Based on the data of the temperature dependence of magnetization and μe, the achievement of the soft magnetic properties is presumably due to the amorphous phase along the grain boundary of the bcc phase which has a Curie temperature (Tc) high enough to maintain the magnetic coupling between bcc grains. The residual existence of the amorphous phase causes the suppression of grain growth of the bcc phase and the precipitation of compounds from the crystallization of the remaining amorphous phase results in the decrease in μe. It is therefore concluded that the residual existence of the amorphous phase with high Tc plays an important role in the achievement of the good soft magnetic properties, in addition to the small grain size and low magnetostriction of the bcc phase.View full abstractDownload PDF (1073K) -
Satoshi Hashimoto, Yasuharu Aoki, Zhao-Yan Wang, Sei Miura1993 Volume 57 Issue 8 Pages 972-973
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSDownload PDF (243K)
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