All issues
Volume 57, Issue 10
Displaying 1-18 of 18 articles from this issue
- |<
- <
- 1
- >
- >|
-
Kenji Matsuda, Susumu Ikeno, Shizuo Tada1993 Volume 57 Issue 10 Pages 1107-1113
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe rod-shaped precipitates in an Al-1.0 mass%Mg2Si alloy were observed by a transmission electron microscope in order to clarify about their crystal structure.
The micro-beam diffraction (MBD) patterns obtained from the direction parallel to the longitudinal direction of precipitates show that there are rotating relationships between the matrix ⟨100⟩ direction and the longitudinal directions of the precipitates. The rotating axis is parallel to the longitudinal direction of the precipitates. When the precipitates were observed from the direction normal to their longitudinal direction and parallel to the ⟨100⟩ or ⟨310⟩ matrix directions, three kinds of selected area diffraction patterns are obtained. These diffraction patterns are explained by the rotating relationships between the matrix and the precipitates.
Based on the results in this study, the crystal structure of this precipitate is proposed as follows: The crystal system is H.C.P. whose unit cell contains four Mg and two Si atoms (Mg/Si=2.0) and its lattice parameters are a=0.407 nm and c=0.405 nm. The electron diffraction patterns observed are in agreement with the computer simulated patterns based on the crystal structure of the rod-shaped precipitate.View full abstractDownload PDF (942K) -
Kouji Tanaka, Takashi Saito, Yoshio Shimura, Kazuhiko Mori, Minoru Kaw ...1993 Volume 57 Issue 10 Pages 1114-1122
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSA new type copper-based alloys for valve seat of automotive engines have been developed, which were directly deposited onto aluminium-alloyed cylinder head by a laser cladding technique.
These alloys have unique microstructures resulted from a rapid solidification of immiscible two liquid phases, in which coarse grains containing fine hard particles of borides and/or silicides (from liquid B) are homogenously dispersed in the heat-resistant copper-based solid solution (from liquid A).
The controlled irradiation of a high-frequency oscillated CO2 laser beam results in melting only the material powder for cladding on the aluminium-alloyed substrate and stirring the molten pool to form a homogeneous dispersion of liquid B in liquid A, and then rapidly solidified to freeze the dispersion by the heat conductivity the aluminium-alloyed substrate.
The deposited alloys provided considerable abrasive- as well as adhesive-wear resistances at a wide temperature range owing to the unique microstructures consisting of hard particles, heat-resistant matrices and/or lubricating phase.View full abstractDownload PDF (1604K) -
Teruo Asaoka, Hideaki Yamashita, Hideo Saito, Yoichi Ishida1993 Volume 57 Issue 10 Pages 1123-1129
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe effect of a small amount of hydrogen on the cyclic pseudo-elastic properties of a Ti-Ni alloy has been studied. A cyclic test machine and control systems were constructed for the study. A decrease in the pseudo-elastic properties due to the absorption of a small amount of hydrogen was observed. Hydrogen seems to reduce or shift the stress-temperature range for the appearance of pseudo-elasticity. The changes in pseudo-elastic properties during the cyclic test were attributed to the accumulation of plastic strain at local regions such as grain boundaries and hydrogen induced decrease in the critical stress for slip deformation. Hydrogen is thought to have an interaction with dislocations and lead to the local formation of stress induced martensites. Dissolved or trapped hydrogen, or both, are supposed to have played an important role during the processes.View full abstractDownload PDF (727K) -
Shigeru Kuramoto, Motohiro Kanno, Goroh Itoh1993 Volume 57 Issue 10 Pages 1130-1135
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSPlastic flow localization at the liquid helium temperature has been investigated for Al-Zn-Mg base alloys (7020), which have been applied for cryogenic propellant tankage. As the specific heats of metallic materials decrease with decreasing temperature, a temperature increase produced by plastic work at cryogenic temperatures will be appreciably higher than that produced at room temperature. This temperature rise in the deformed region can make the flow stress significantly lower than otherwise, giving rise to a serrated stress-strain curve at the temperatures below 40 K. In the present work, changes in test piece profiles are studied through the high magnification recording by use of a surface roughness measuring instrument. As a result, each load drop during serrated flow corresponds to a neck formation, which has been observed in ferrous alloys and titanium alloys. It should be noted that necking accompanied by each load drop is outstanding particularly in the specimens with a strong texture that arose from rolling or extruding. In these textured specimens, the sudden rise in temperature allows a great number of grains to deform all at once since the schmid factor of each grain is almost alike. Besides the texture, strain hardening also affects the characteristics of the locallized plasticity. The extruded specimen that has the [111] fiber texture exhibits higher strain hardening rate and higher flow stress level at large strain than other specimens. For this reason, larger local reduction accompanied by each load drop is observed in the cross-sectional area of the extruded specimen.View full abstractDownload PDF (674K) -
Akira Nozue, Hyoe Sakamaki, Yoji Saita, Tadatsune Okubo1993 Volume 57 Issue 10 Pages 1136-1140
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSA special aging treatment has been developed to decrease the susceptibility to hydrogen embrittlement in high-strength Ti-15V-3Cr-3Sn-3Al alloys. Hydrogen embrittlement tests were carried out with CT specimens under a constant loading condition. Hydrogen was occluded into the specimens with a cathode charging method during the tests.
The formation of fracture-resistant precipitate-free zones and the precipitation of an adequate amount of α phases in β grains are found to be effective in preventing the hydrogen embrittlement and in retaining a high strength. A two-step aging treatment is proposed to obtain this desired microstructure. After the first aging for a short time, the precipitate-free zones form and a small fraction of the α precipitates exists within the grains. After the secondary aging at a lower temperature, the specimens contain a high fraction of the precipitates within the grains while still retaining the precipitate-free zones. This process makes it possible to obtain the desirable mechanical properties of the present alloy.View full abstractDownload PDF (863K) -
Masae Sumita, Norio Maruyama, Kouzou Nakazawa1993 Volume 57 Issue 10 Pages 1141-1148
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe fretting fatigue strength at 107 cycles was 106 MPa in the SiCw/7075-T6 Al composite, and 62 MPa in the 7075-T6 alloy. The fatigue strength at 107 cycles was 155 MPa in both the materials.
A method to evaluate the role of reinforcement phase in fatigue strength and fretting fatigue strength in a metal matrix composite was proposed, which distinguish the increase in the fatigue and fretting fatigue strengths due to the increase in ulutimate tensile strength by reinforcement from the increase in the strengths of the composite materials.
The results of the evaluation of the fretting fatigue strength at 107 cycles in the SiCw/7075-T6 alloy composite on the basis of the above method was that the gross increase was 44 MPa (70%) and the net increase was 38 MPa (57%) in the strength due to the reinforcement, compared with the strength in the 7075-T6 alloy. It seems that the net increase in the strength in the composite is owing to the low stress concentration in the fretted area and the restriction of crack initiation by reinforcement.
The practical value of the fatigue strength at 107 cycles in the SiCw/7075-T6 alloy composite is nearly equal to the estimated value. The crack was initiated from the defect whose size was 150∼200 μm.
The effects of SiC wisker reinforcement on the friction coefficient, main crack initiation site on the fretted area, paring off of microcracks by pad, crack initiation, and crack propagation in the composite materials were discussed.View full abstractDownload PDF (1373K) -
Hiroyuki Fukuyama, Eisaku Wada, Toshiharu Fujisawa, Chikabumi Yamauchi1993 Volume 57 Issue 10 Pages 1149-1157
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThermodynamic properties of NaO0.5-CO2-FeO1.5 slag have been investigated for the application of sodium carbonate slag to the elimination of Fe from molten copper. The activities of NaO0.5 and Na(CO3)0.5 were measured by the EMF method, using beta′′-alumina as a solid electrolyte, for various partial pressures of CO2 at 1423 to 1523 K. There is a stable solid compound NaFeO2 in this system, and the solubility measurement of this compound into sodium carbonate melt at 1523 K revealed that the solubility is very limited and controlled by the partial pressure of CO2. The dissolution reaction seems to proceed according to the following reaction and Fe exists as FeO33− anion in the sodium carbonate-based melt.
(This article is not displayable. Please see full text pdf.)
\ oindentThe standard free energy change for the following reaction:
(This article is not displayable. Please see full text pdf.)
\ oindentwas also determined by the EMF method as:
(This article is not displayable. Please see full text pdf.)
\ oindentThe activity of FeO1.5 in the (solid NaFeO2+liquid) two phase region could be calculated from the activity of NaO0.5 via the above equilibrium relation. Distribution equilibrium measurements were also conducted for Fe between the slag and molten copper at 1523 K not only to confirm the calculated results but also to determine the activity of FeO1.5 in the homogeneous liquid region of the slag. The activity coefficient of FeO1.5 in the homogeneous liquid region has a constant value for a constant CO2 partial pressure, independent of the concentration.View full abstractDownload PDF (944K) -
Ken-itsu Tanaka, Ken Takeuchi, Toyonobu Yoshida1993 Volume 57 Issue 10 Pages 1158-1165
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe plasma conditions needed for diamond growth under microwave plasma jet were characterized by emission spectroscopy and mass spectroscopy, and numerical calculations on gaseous reactions in the plasma was carried out for better understanding the complicated reactions in the plasma flame. The temperature of the plasma flame was estimated to be in the range of 4000∼6000 K based on the emission spectroscopy. The mass spectroscopy revealed that the main species impinging to the substrate were Ar, H, H2, CHx (x=0∼4), and C2Hx (x=0∼6). The flux of CH3 and CH4 was observed to be almost independent of the composition ratio CH4/H2 in the fed gas, though the flux C2H2 and C2H4 was in proportion to the ratio. The numerical calculations revealed that reactions in the boundary layer just above the substrate have a great influence on the composition of the impinging species to the growing surface, though it predicted a little larger amount of C2H2 concentration and a much smaller amount of CH4, CH3 and C2H4 than the value derived from mass spectroscopy, which may be caused by neglecting some reactions including ionic species whose rate constants are currently unknown. Nevertheless, the predicted tendency relating to the dependence of the main species concentration on the fed gas composition was in good agreement with the result derived from mass spectroscopy. At this stage, it was difficult to discuss about the chemical species responsible for diamond growth quantitatively, however, such a numerical modeling was found to be very useful for designing the process for diamond deposition.View full abstractDownload PDF (656K) -
Daisuke Tanaka, Noboru Akao, Nobuyoshi Hara, Katsuhisa Sugimoto1993 Volume 57 Issue 10 Pages 1166-1173
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe anodic polarization behavior of SiC prepared by CVD has been examined in 1 kmol·m−3 H2SO4 (pH0), phosphate buffer solution (pH6.86), boric-borate buffer solution (pH8.45) and 0.1 kmol·m−3 NaOH (pH12.8). Growth and composition of the surface film formed by the anodic polarization have been measured by ellipsometry, XPS, and IR spectroscopy.
Maximum dissolution current densities under the anodic polarization were less than 1 A·m−2 in the solutions. This shows the corrosion rate of SiC is quite small in the solutions. The corrosion rate of SiC increased with increasing the pH value of solutions. The anodic oxidation films which was estimated to be a hydrated amorphous SiO2 by XPS and IR spectroscopy were formed on SiC in the acid and neutral solutions, whereas no film growth was found in the alkaline solution. The potential at which the formation of anodic oxidation film starts became lower with increasing pH. The conversion of composition of the SiC matrix occurred under the anodic oxidation film when SiC was polarized to higher potentials. This converted matrix layer was composed of carbon-rich SiC and its refractive index was lower than that of the original SiC matrix.View full abstractDownload PDF (917K) -
Norihito Ikemiya, Shigeta Hara, Kazumi Ogino, Tsuyoshi Nakajima1993 Volume 57 Issue 10 Pages 1174-1179
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSAtomic force microscopy (AFM) has been used to study the interface structure of stage-1 and stage-2 fluorine-graphite intercalation compounds (CXF) synthesized under the gaseous HF. The results obtained are summarized as follows;
(1) It is difficult to prepare the atomically-flat surfaces of the stage-1 CXF by cleaving.
(2) We have recognized a well ordered 2×\sqrt3 and 1×\sqrt3 superlattice structures of fluorine atoms with twofold symmetry on the cleaved surfaces of the stage-1 CXF synthesized from natural graphite. This suggests that the 1×1 ordered structure and the new 1×\sqrt3 superlattice structure of fluorine atoms coexist in the interface of the stage-1 CXF.
(3) Only the graphitic surface structure has been observed on the cleaved surfaces of the stage-2 CXF. This suggests that the cleavage occurs at the graphite layer having the weak bonds preferentially.
(4) We have found that the force between the tip of AFM and a sample surface for the intercalant layer of CXF is larger than that for the graphite layer.View full abstractDownload PDF (1005K) -
Shigeo Matsubara, Kazunari Nakamoto, Yusuke Hirose, Iwao Katayama, Tak ...1993 Volume 57 Issue 10 Pages 1180-1185
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSControl of the aluminum concentration in a hot dip galvanizing bath is of great importance for producing galvannealed steel sheets. Since aluminum has much greater affinity for oxygen than zinc, the oxygen potential of Zn-Al-O bath may be determined only by the following equilibrium reaction;
(This article is not displayable. Please see full text pdf.)
\ oindentwhen the aluminum concentration in the bath is relatively low. Aluminum sensor with the zirconia solid electrolyte has been devised by utilizing the above equilibrium relation, i.e., from the oxygen potential of the bath, aluminum concentration is derived indirectly.
In this paper, in order to determine the optimum cell construction for the sensor, emf measurements have been carried out in a pure zinc bath melted in the air atmosphere by using various zirconia solid electrolytes and liquid reference electrodes. From the analysis of a series of emf measurements, the following cell constructions were found to be optimum for measuring the oxygen potential of the bath.
(This article is not displayable. Please see full text pdf.)
The emfs measured with these cells agreed fairly well with the extrapolated values from the thermodynamic data measured at higher temperatures. Also, the possibility of the present method has been ascertained in Zn-Al-O baths.View full abstractDownload PDF (763K) -
Shinji Itoh, Fumio Hirose, Shin’ichi Hasegawa, Ryosuke Hasegawa1993 Volume 57 Issue 10 Pages 1186-1191
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSUsing a VG 9000 glow discharge mass spectrometer, analysis of titanium alloys has been studied. Concentrations of not only trace impurity elements (Si, Ni, Cu and W) but also alloying elements (Al, V, Fe, Zr, Mo, and Sn) were successfully determined for pin samples. The analytical accuracy obtained was comparable to that of ordinary XRF analysis. The optmium discharge conditions including preliminary sputtering were examined. Observation of spectral interferences clarified that vanadium argide (51V40Ar) considerably affects the spectrum of 91Zr. Relative sensitivity factors (RSFs) were determined from the analysis of the standard reference materials: NIST SRM, BS CRMs, IMI CRM and the alloys prepared in our Institute. The average RSF-values obtained for the analytes were Al 3.33, V 1.40, Cr 7.09, Fe 2.94, Zr 1.59, Mo 3.92 and Sn 8.89. Using these RSF-values, the GDMS analytical values were corrected on a personal computer to the values with an accuracy (σd) ranging from 0.065 (V) to 0.16 (Al).View full abstractDownload PDF (565K) -
Yukio Nishikawa, Yoshikazu Yoshida, Yuji Uesugi1993 Volume 57 Issue 10 Pages 1192-1198
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe characteristics of metal films deposited using a KrF excimer laser ablation technique are determined by X-ray diffraction and transmission electron microscope. Spectroscopic observation and mass-spectroscopic studies are carried out to analyze species during laser ablation. Furthermore, the kinetic energy of the ions are determined using an electrostatic energy analyzer to discuss the influences of ions on the film structure. The main results obtained are as follows.
(1) Cu, Ni, Ni-Cu and Ni-Fe films deposited on the glass substrate at room temperature show strong diffraction from the (111) plane. Fe film shows strong diffraction from the (110) plane. The grain size of the Cu film deposited on the Si(100) substrate is in the range of 5 to 230 nm. These films are formed by the deposition of neutral atoms and ions following laser ablation of metals and alloys.
(2) The Ni film deposited using a laser ablation technique shows stronger diffraction from the (111) plane rather than one using a magnetron sputtering technique. The Ni+ with the high kinetic energy of 60 eV following laser ablation is considered to promote the migration of atoms on the substrate and contribute to the preferred (111) plane growth.
(3) The orientation of the films depends on the substrate temperature. The Ni film deposited at 573 K shows strong diffraction from the (200) plane.View full abstractDownload PDF (906K) -
Saburou Ohtani, Masanori Watanabe, Toshinori Takagi1993 Volume 57 Issue 10 Pages 1199-1203
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn order to extend the thickness of ion implantation layer, Fe and Fe-Ti alloys were implanted at 200∼500°C with N2+ ions of 4.5×1021∼2×1022/m2 accelerated at an energy of 2.89×1010 J/mol (300 keV), and then the effect of the temperature on the N distribution, precipitates and surface hardness was studied. N atoms implanted at 200°C on each substrate, move little distance and the distribution is close to the figure which is computed under the condition of no thermal diffusion. On the other hand, there is marked change in the N distribution in the specimens implanted at more than 350°C; in the Fe substrate, the N atoms move toward surface side and inner N concentration decreases, and in the Fe alloys with content of 3∼22 at%Ti, N atoms distribute in a figure that extend at the concentration corresponding to that of Ti, with slight decrease from the surface to the inner region determined by the dose and Ti content. It is thought that this extension of N atoms implanted at a temperature higher than 350°C corresponds to the phenomena in which Fe nitrides decompose and reprecipitate as TiN. In the case of an Fe-65 at%Ti alloys containing a large Ti amount, N atoms implanted with a small dose is distributed as in the computed shape, and at a large dose of more than 1×1022 N2+/m2, in a trapezoidal distribution extending to both sides with the projected range as the center. Greater improvement in surface hardness can be achieved in the Fe-Ti alloys by implantation at 350∼500°C, than at 200°C.View full abstractDownload PDF (576K) -
Yuichi Sato, Kazuhiko Fukutani, Minoru Yamate1993 Volume 57 Issue 10 Pages 1204-1208
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSCasting examination was carried out to investigate the influence of wheel surface velocity and ejection gas pressure on the thickness of ribbon produced by Planar Flow Casting in vacuum. Fe80.5Si6.5B12C1 (amorphous forming alloy) was cooled rapidly on a wheel made of Cu-1 mass%Cr under the pressure of 10−3 Pa. Nozzle orifice dimension was 0.6 mm×12 mm. As the wheel surface velocity increased, the thickness of ribbon obtained decreased. The thickness of the ribbon is determined by contact time between melt puddle and the wheel surface. The contact time (τ) is written as, τ=Lp⁄V where Lp is the length of the melt puddle in the direction of wheel revolution and V is the wheel surface velocity. Thus, the contact time depends on the length of the melt puddle in the direction of wheel revolution and the wheel surface velocity. Observations of the melt puddle with an optical microscope and a video camera indicated that the length of the melt puddle decreased as the wheel surface velocity increased. On the other hand, the thickness of the ribbon increased as the ejection gas pressure increased. The increase of the ejection gas pressure seems to cause the increase of the amount of the molten alloy ejected from the nozzle. Actually, it was found from the observations of the melt puddle that the length of the melt puddle increased as the ejection gas pressure increased. Further, the increase in solidification rate with increasing ejection gas pressure also increases the ribbon thickness.View full abstractDownload PDF (835K) -
Minoru Umemoto, Takayuki Norimatsu, Tsuyoshi Itsukaichi1993 Volume 57 Issue 10 Pages 1209-1214
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe crystal structure, formation condition and thermal stability of the newly found phase in the mechanically alloyed (MA) and subsequently heat treated Al-Ni-Ti powders have been studied. MA powders of the Al-Ni-Ti system were prepared by laboratory ball milling starting from elemental powders. The structural changes of the MA powders upon subsequent heating have been investigated by using X-ray diffractometry (XRD) and thermal analysis. The crystal structure of this new phase (χ phase) was found to be similar to that of the NiTi2 intermetallic compound. The lattice parameter of the χ phase is about 0.022 nm larger than that of NiTi2 phase. Several differences in the relative X-ray intensity were observed between these two sets of XRD peaks: in χ phase {600, 442} diffraction is much weaker and {331} diffraction is much stronger than those of NiTi2 phase. The χ phase has been observed in the wide composition range of ternary Al-Ni-Ti system (15∼55 at%Al, 5∼45 at%Ni, 15∼65 at%Ti). Depending on the composition, the χ phase coexists with NiTi2, AlTi, AlTi3, AlNi2Ti, AlNiTi or Al2NiTi phases. By heating MA Al45Ni10Ti45 powders to 973 K, a practically single χ phase was obtained. For some compositions, the χ phase seems to form from amorphous phase or from the AlNi2Ti compound and to decompose partially into several different phases by heating up to 1173 K. The χ phase is considered to be a stable phase since it is stable after 86.4 ks annealing at 1373 K. A cast alloy or rapidly solidified alloy of the same composition did not show any trace of the χ phase, but only the phases expected from the equilibrium phase diagram. The hydrogen and carbon from methanol (a process agent) or iron and chromium from milling balls and vial are excluded from the origin of the formation of χ phase. Oxygen with less than 1 mass% introduced by mechanical alloying is considered to be responsible for the formation of χ phase.View full abstractDownload PDF (671K) -
Hiroyuki Izumi, Hideyuki Saitoh, Akihiko Kimura, Toshihei Misawa1993 Volume 57 Issue 10 Pages 1215-1220
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe effects of composition, atmosphere, deformation rate, temperature and the addition of the third elements of iron and aluminum on environmental embrittlement in Co3Ti intermetallic compounds have been investigated by the small punch (SP) testing. It has been found that the SP-fracture energy significantly depends on the specimen composition, environment, testing temperature and deformation rate. The SP-fracture energy for Co-23.1 mol%Ti remarkably decreases in the range of 200 to 400 K around at room temperature in air. This embrittling region tends to expand with decrease in deformation rate. Co-21.1 mol%Ti shows a lower susceptibility to environmental embrittlement than near stoichiometric Co-23.1 mol%Ti. A remarkable decrease in SP-fracture energy has been clearly observed even in a high vacuum of 8×10−5 Pa at room temperature in Co-23.1 mol%Ti. Intergranular cracking becomes dominant as the SP-fracture energy decreases. It is suggested that environmental embrittlement in the Co3Ti intermetallic compounds in air at room temperature is caused by hydrogen embrittlement. The curves of SP-fracture energy against test temperature for Co-21.4 mol%Ti-2.9 mol%Fe and Co-20.9 mol%Ti-2.1 mol%Al show a lower susceptibility to hydrogen embrittlement than that for Co-23.1 mol%Ti. The addition of iron significantly reduces the susceptibility to hydrogen embrittlement of Co3Ti.View full abstractDownload PDF (1080K) -
Kazuhiko Majima, Norikazu Niimi, Masanobu Watanabe, Shigeru Katsuyama, ...1993 Volume 57 Issue 10 Pages 1221-1226
Published: 1993
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn the present work, the preparation of transparent yttria ceramics by vacuum hot pressing was investigated, using yttria powder whose mean diameter is 0.88 μm and whose purity is higher than 99.9%.
Transparent yttria ceramics were fabricated by vacuum hot pressing with small additions of LiF (∼1 mass%). Hot pressing temperature and pressure were kept at 1573 K and 44 MPa, respectively. The processed samples were observed to have transparencies up to 78% at 644 nm frequency and over 80% in the range of 860 nm-6 μm.View full abstractDownload PDF (2681K)
- |<
- <
- 1
- >
- >|