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Volume 46, Issue 12
Displaying 1-21 of 21 articles from this issue
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Takashi Sakamoto, Minoru Nishida, Kenji Okazaki1999 Volume 46 Issue 12 Pages 1221-1225
Published: December 15, 1999
Released on J-STAGE: May 22, 2009
JOURNAL OPEN ACCESSWhen Ni or Ni3Al powders are added to Mo powders, sintering is greatly promoted to result in significantly higher densities even at lower temperatures than one-half of the homologous temperature for Mo. The activation energies obtained for mixed sintering are lower than that required for mutual volume diffusion between Mo and Ni.
TEM observations of microstructure after sintering Mo and Ni powders at 1573 K revealed the formation of a MoNi phase at interfaces of Mo particles. When sintered at 1673 K, not only Mo-Ni phase is seen at the interface but also the Mo particle surface became slightly wavy as a result of contacting with the liquid Mo-Ni phase.
When Mo powders were sintered with a 5 wt.% of Ni3Al alloy powders at 1573 K, the microstructure obtained by quenching from this temperature is a mixture of Mo and Ni3Al. But the microstructure obtained by furnace-cooling is a mixture of Mo, Mo-Ni and Ni3AI which is surrounded by MoNi3.View full abstractDownload PDF (2925K) -
Kazuo Isonishi, Masako Hamada1999 Volume 46 Issue 12 Pages 1226-1231
Published: December 15, 1999
Released on J-STAGE: December 04, 2009
JOURNAL OPEN ACCESSThe effect of ductile second phase of Ti5Si3 base intermetallic compounds on mechanical properties was studied. In this study, α-Ti (hcp) or β-Ti (bcc) are chosen as the second phase. It is necessary to add ternary element to make the β phase stable at room temperature. Chemical compositions of materials investigated here are Ti-32mol%Si (Ti5Si3+α-Ti), Ti-32mol%Si-10mol%V (Ti5Si3+β-Ti) and Ti-32mol%Si-5mol%Mo (Ti5Si3+β-Ti), those were fabricated by mechanical alloying and vacuum hot pressing method. Mechanical properties from room temperature to 1373K were investigated by micro-Vickers hardness tester to show the effect of ductile phase and also ternary element, V or Mo. V addition was effective to increase fracture toughness, KIC, at R.T. The KIC value of Ti-32Si-10V compact was 4.43MPa⋅m1/2 which was about 1.7 times larger than Ti5Si3 monolithic compact. Ti-32Si-5Mo compact behaved superior high temperature properties in comparison with Ti-32Si-10V compact.View full abstractDownload PDF (4100K) -
[in Japanese]1999 Volume 46 Issue 12 Pages 1234
Published: December 15, 1999
Released on J-STAGE: May 22, 2009
JOURNAL OPEN ACCESSDownload PDF (92K) -
Setsuo Takaki, Yuji Kimura1999 Volume 46 Issue 12 Pages 1235-1240
Published: December 15, 1999
Released on J-STAGE: May 22, 2009
JOURNAL OPEN ACCESSMechanical milling treatment of iron powder was applied as the technique to charge an extremely large strain into iron matrix. Milling treatment using high energy vibration ball mill enable a significant work hardening of iron to Hv950 after a long time milling, whereas the maximum hardness achieved by conventional cold-rolling process for bulk iron is small as Hv280. For the mechanically milled iron powder with the hardness Hv950, the grain size is refined to several tens nm due to super heavy deformation through mechanical milling. On the annealing of this mechanically milled powder, it was confirmed that softening occurs not through the well-known recrystallization process but through gradual grain growth of such fine grains. The hardness of iron powders yields the Hall-Petch relation to the grain size, in the case they do not have substructures within each grain such as dislocation cells and subgrains. Mechanically milled iron powder can be consolidated to the bulk with full density at the low temperature of 923K and the grain size is kept at about 0.2mm due to the grain boundary pinning effect of finely dispersed oxide particles. 0.2% proof stress of this bulk iron is increased to about 1.6Gpa by grain refining strengthening. The behavior of grain refining strengthening is identical in both steels of fcc and bcc structure regardless of the crystal structure.View full abstractDownload PDF (1990K) -
Uichiro Mizutani, Tetsuo Oka, Yoshitaka Itoh, Hiroshi Ikuta1999 Volume 46 Issue 12 Pages 1241-1248
Published: December 15, 1999
Released on J-STAGE: May 22, 2009
JOURNAL OPEN ACCESSThe c-axis oriented single-domain Sm123 bulk superconductors have been synthesized in the melt-texturing process. The maximum trapped flux density has reached 1.7 T at 77 K and 9.0 T at 25 K at the center of sample surface. Detailed analysis on the flux motion through the pulsed field magnetization (PFM) process revealed that the iteratively magnetizing pulsed field operation with reducing amplitude (IMRA method) is very effective in magnetizing high Jc bulk superconductors at temperatures near 30K, attained by a cryocooler and vacuum pumps. A compact superconducting permanent magnet system driven by the PFM technique has been constructed, which is capable of generating magnetic fields up to 2 T in the open space outside the magnetic pole.View full abstractDownload PDF (3463K) -
Kota Kataoka, Toshihiro Tsuchiyama, Hideto Goto, Setsuo Takaki1999 Volume 46 Issue 12 Pages 1249-1255
Published: December 15, 1999
Released on J-STAGE: May 22, 2009
JOURNAL OPEN ACCESSA few kinds of high nitrogen powders (nitride (Cr2N), atomized 23mass%Cr steel with 4mass%N (AT-4N), mechanically milled 23mass%Cr steel with 4mass%N (MM-4N)) were mixed with nitrogen-free powders (atomized 16mass%Cr steel, atomized 23mass%Cr steel (AT), mechanically milled 23mass%Cr steel (MM)) to fabricate the high nitrogen stainless steel of the mean chemical composition; Fe-23mass%Cr-lmass%N. The powder mixtures were packed in stainless steel tubes in vacuum and then consolidated by hot rolling for densification. The consolidated materials were annealed at 1473K for 1.8ks for the purpose of homogenization. In the powder mixtures, in which the Cr2N or the AT-4N powder was added as the nitrogen supplier, full densification was not performed. In the case that the MM-4N powder was added as the nitrogen supplier to the nitrogen-free MM powder, the powder mixture was consolidated to the material with full density. The structure is of austenite with the grain size of about 5μm. The austenitic steel has much higher strength and elongation than the sintered material with the same composition, because of its fine grained structure and its full density.View full abstractDownload PDF (7357K) -
Hideyuki Hidaka, Yuuji Kimura, Setsuo Takaki1999 Volume 46 Issue 12 Pages 1256-1260
Published: December 15, 1999
Released on J-STAGE: July 12, 2010
JOURNAL OPEN ACCESSThe mechanically milled Fe-0.8mass%C alloy powder (MM powder) was packed in stainless steel tubes and hot-rolled to consolidate powder to the bulk material with full density (MM bulk material), and the mechanism during consolidation of the MM powder was investigated by means of tensile testing at the consolidation temperature (973K) using the MM bulk material. The MM bulk material has micro-duplex structure which consists of ferrite and cementite grains of the size; 0.3μm. The deformation stress of the MM bulk material is small as 80MPa at 973K, while high as 1700MPa at room temperature. Although the total elongation was not so large (about 100%) under the condition of strain rate; 10-2-10-1/s-1 at 973K, the m value was estimated at 0.3. Besides, it was confirmed that there were few dislocations within ferrite grains after tensile testing. These results demonstrate the fact that the MM bulk material deforms through the grain boundary sliding. Since the grain size in MM powder before consolidation (about 0.1μm) is smaller than that in the MM bulk material (about 0.3μm), MM powder is through to undergo superplastic deformation based on grain boundary sliding during the consolidation by hot-rolling.View full abstractDownload PDF (6084K) -
Tomohiro Takida, Tadashi Igarashi, Naobumi Saito, Mamoru Nakamura1999 Volume 46 Issue 12 Pages 1261-1267
Published: December 15, 1999
Released on J-STAGE: July 12, 2010
JOURNAL OPEN ACCESSFine-grained sintered molybdenum alloys dispersed with TiC, ZrC, HfC or TaC particles of 0.8 mol.% were prepared by mechanical alloying and hot isostatic pressing. The grain sizes of molybdenum and the particle sizes of carbide particles in the alloy were 0.2-10μm and 20-100 nm, respectively. Grain growth of the alloy was measured to evaluate the stability of the fine-grained microstructure at 1670 K to 2470 K. The following results were obtained.
(1) The grain growth was inhibited significantly more in the molybdenum alloy with carbide particles than in puremolybdenum. The grain growth stopped in 3.6-36 ks.
(2) The dispersion of the ZrC or HfC particles in the alloy was more efficacious against inhibition of grain growth than the dispersion of the TaC or TiC particles.
(3) The grain boundary character distribution in the alloys showed almost no change even after heated at high temperature of 2070K.View full abstractDownload PDF (6075K) -
Chuji Kawamura, Eiji Yuasa, Masaomi Tamura1999 Volume 46 Issue 12 Pages 1268-1273
Published: December 15, 1999
Released on J-STAGE: May 22, 2009
JOURNAL OPEN ACCESSIn order to obtain aluminum alloy powder which composes of α-Al phase super-saturated with titanium and boron, the titanium and boron powders were mixed with various amounts of molar ratio Ti/B=1/2, to aluminum powder and then the mixture was mechanically alloyed for 108ks. The alloy powder was heat-treated for various times at 723-873K in argon atmosphere. It was observed that the structural change of the alloy powder with the heat-treatment by XRD, SEM and EPMA. When the Al-10-20mass%(TiB) powder heat-treated at 700-800K for treating time up to 3.6ks, Al3Ti, Al5Ti2 phases and diborid particles as TiB2 and AlB2 precipitate from the super-saturated α-Al phase, and these precipitates become to Al3Ti and TiB2 by the treating for long time. In the heat treatment at 873K for 3.6ks more than, Al3Ti phase ceased to exist, and only TiB2 existed in α-Al phase. The powder was consolidated at 873K for 5.4ks under various pressures. The Al-15-20mass%(Ti/B) alloys produced by the hot-pressing of about 300MPa become higher strength due to the precipitation-hardening and the dispersion of fine TiB2 particles.View full abstractDownload PDF (4407K) -
Hiroshi Kimura, Yusuke Fujimoto1999 Volume 46 Issue 12 Pages 1274-1278
Published: December 15, 1999
Released on J-STAGE: December 04, 2009
JOURNAL OPEN ACCESSThis article reports the solid state synthesis and high-speed superplastic forging of the fully dense nanocrystalline ZrO2-20mol%Al2O3 product via the thermal-mechanical testing combined with the pulse discharging and d.c. heating. The full-density cylindric specimen with the height, 9.8 mm can be obtained by the consolidation of the amorphous ZrO2-20mol%Al2O3 powder compact at the relatively low temperature of 1331 K, when the pressure of 160 MPa is applied. For bulk nanocrystalline ZrO2-20mol%Al2O3 with a grain size (d) of 11 nm for tetragonal ZrO2 as deduced from X-ray diffraction, we find that the sample can be plastically forged up to the compressibility of 43 % during heating in a range of testing temperature from 1175 to 1377 K without macroscopic fracturing. The strain rate of nearly uniaxial plastic deformation at the early stage of forging shows an extremely high level of 2⋅10-2 s-1 at 1358 K under an initial uniaxial stress (σ) of 100 MPa, and is characterized by an activation energy (Q) of 457 kJmol-1 according to the usual constitutive law of ε=Aσ1/m(1/d)P exp (-Q/kT) for superplastic flow.View full abstractDownload PDF (1824K) -
Rotating-Arm Reaction Ball Milling for Mechanical Alloying and Solid State Amorphication of CeramicsHiroshi Kimura, Kenji Hanada1999 Volume 46 Issue 12 Pages 1279-1283
Published: December 15, 1999
Released on J-STAGE: May 22, 2009
JOURNAL OPEN ACCESSFar from equilibrium rotating-arm reaction ball milling is developed for the mechanical alloying and solid state amorphization of ceramic materials. This processing provides peripheral equipments for the measurements of the temperature inside the PSZ tank and the torque applied to PSZ agitating-arms for the efficient and high quality production of amorphous (a) ceramic powders. We find that the mechanical alloying of powder mixture, PSZ-20mass%Al2O3 can produce the solid state amorphization in the multilayer (ml), according to a single reaction of ml-(PSZ/20mass%α-Al2O3)→a-(3mol%Y2O3-ZrO2)80(Al2O3)20. The reaction milling method can be used to determine the starting time (ts) of the exothermic amorphization at the plateau attrition temperature. The analysis of Johnson-Mehl-Avrami equation with X=1-exp{-k(t-ts)n} shows that the isothermal amorphization obeys an exponential growth law with n=0.5 by using volume fractions (X), as obtained by X-ray diffraction method, of amorphous (3mol%Y2O3-ZrO2)80(Al2O3)20. Furthermore, our dry attrition milling realizes free from the contamination of Iron incorporated in the amorphous ZrO2-20mol%Al2O3 particle, when compared with the previous result.View full abstractDownload PDF (1937K) -
Benjamin D. Hatton, Tohru S. Suzuki, Yoshio Sakka1999 Volume 46 Issue 12 Pages 1284-1291
Published: December 15, 1999
Released on J-STAGE: May 22, 2009
JOURNAL OPEN ACCESSAl2O3-dispersed ZrO2-3mol%Y2O3 composites have been prepared by slip casting and electrophoretic deposition to compare the sinterability and microstructure, using three commercially-available Al2O3 powders. Composites were prepared by pressureless sintering at 1300°C. The consolidated (green) density, sintered density, grain size and dispersion are compared for both colloidal techniques with the aim of improving the homogeneity and reducing the necessary temperature for sintering.View full abstractDownload PDF (4587K) -
Yoshikazu Suzuki, Masanobu Awano, Naoki Kondo, Tatsuki Ohji1999 Volume 46 Issue 12 Pages 1292-1296
Published: December 15, 1999
Released on J-STAGE: May 22, 2009
JOURNAL OPEN ACCESSFine-grained 3Y-TZP/β-Al2O3 (-NaAl11O17) composites have been prepared by pressureless sintering of planetary-ball-milled 3Y-TZP and, β-Al2O3 powders. In the composites, β-Al2O3 particles with about 0.2-3μm in size were homogeneously dispersed in the TZP matrix with the grain size of-200 nm. The β-Al2O3 addition slightly improved Vickers hardness and fracture strength. Fracture toughness of the composite, however, was almost the same as that of the pure TZP and neither crack bridging nor crack deflection was observed for the composites. This result indicates that rather strong bonding may exist between 3Y-ZrO2 matrix and fine β-Al2O3 particles.View full abstractDownload PDF (5343K) -
Mamoru Okubo, Junichi Kaneko, Mokoto Sugamata1999 Volume 46 Issue 12 Pages 1297-1302
Published: December 15, 1999
Released on J-STAGE: May 22, 2009
JOURNAL OPEN ACCESSWith a purpose of attesting preferential oxidation of an alloying element which has low solid solubility in aluminum, an AI-5at%Y alloy was mechanically alloyed with or without addition of metal oxides. Y was chosen as an alloying element since it has higher oxidation tendency than Al and a low maximum solid solubility of 0.17mass% in Al. Mechanically alloyed powders were consolidated by hot-extrusion to the P/M materials of which constituent phases, microstructures and mechanical properties were examined. The added oxygen, either from the process control agent or from oxide powders, acted as oxygen sources for internal oxidation, and Y in Al was shown to be preferentially oxidized to Y2O3 and A15Y3O12. The P/M materials with addition of oxide powders showed high tensile strength of about 600MPa at room temperature.View full abstractDownload PDF (4196K) -
Mamoru Okubo, Makoto Sugamata, Junichi Kanedo1999 Volume 46 Issue 12 Pages 1303-1308
Published: December 15, 1999
Released on J-STAGE: May 22, 2009
JOURNAL OPEN ACCESSWith a purpose of attesting preferential oxidation of an alloying element which has low solid solubility in Al, an Al-5at%Ca alloy was mechanically alloyed with or without addition of metal oxides. Ca was chosen as an alloying element since it shows higher oxidation tendency than Al and a low maximum solid solubility below 0.01mass% in Al. Mechanically alloyed powders were consolidated by hot-extrusion to the P/M materials of which constituent phases, microstructures and mechanical properties were examined. The added oxygen, either from the process control agent or from oxide powders, acted as the oxygen sources for internal oxidation and Ca in Al was shown to be preferentially oxidized to CaO and CaAl4O7. The P/M materials with addition of CuO showed high tensile strength of above 500MPa at room temperature.View full abstractDownload PDF (2077K) -
Moritaka Hida, Hiroki Iwabu, Akira Sakakibara, Yoshito Takemoto1999 Volume 46 Issue 12 Pages 1309-1314
Published: December 15, 1999
Released on J-STAGE: July 12, 2010
JOURNAL OPEN ACCESSMechanical grinding (MG) with mechanically stimulated reaction was performed on metal/polymer mixed powders. The starting materials used in this study were the metals of Mg, Ti and Mg2Ni powders, and polymer of PTFE, PVC and PE powders. The MG process was investigated using XRD, IR, SEM and TEM. According to XRD results, magnesium fluoride (MgF2, TiF2) and chloride (MgCl2) were detected from MG products of the Mg/PTFE, Ti/PTFE and Mg/PVC blending systems, respectively. Explosive reaction was found during MG of both Mg/PTFE and Ti/PTFE. It was also confirmed by XRD results that the production of MgF2 had already been formed just before the explosive reaction in Mg/PTFE system. It was found from IR analysis that C-C single bond in the polymers, not only both in PTFE and PVC but also in PE, changed to double bond C=C. Hydrogen produced due to decomposition of PE on blending Mg2Ni/PE was absorbed into C-Mg2Ni-H as amorphous solutes. These mechanically stimulated reaction was powerful method for decomposition of engineering plastics.View full abstractDownload PDF (2376K) -
Baolong Shen, Tohru Yamasaki, Yoshikiyo Ogino1999 Volume 46 Issue 12 Pages 1315-1320
Published: December 15, 1999
Released on J-STAGE: December 04, 2009
JOURNAL OPEN ACCESSNanocrystalline materials structurally stabilized by hard second phases to those materials are usually difficult to make plastic deformation. The application of liquid-enhanced plasticity to those materials is particularly interesting since grain rearrangement by grain boundary diffusion during deformation, which involves sliding and rotation of grains, will be greatly enhanced in nanometer materials as compared with conventional fine-grained materials. In present study, the semi-solid plasticity and diffusion bounding of nanocrystalline Cu-Mg-TiC alloys were investigated. Nanocrystalline Cu-(5 at.%) Mg-(12 vol.%) TiC, Cu-(10 at.%) Mg-(12 vol.%) TiC and Cu-(14 at.%) Mg-(12 vol.%) TiC alloys with grain sizes of about 11 nm, 17 nm and 14 nm were prepared by mechanical alloying, HIP and hot rolling process. The test specimens were prepared from those bulk alloys. Tensile test and diffusion bounding were operated when partial melting occurred. The elongation drastically increased as the melting occurred, and maximum elongations of about 200% were measured at the temperatures where the atomic fractions of the liquid phase were about 0.5. The diffusion bounding at partial melting temperatures also succeeded. After the deformation and bounding, nanocrystalline structures with average grain sizes of about 30 nm were retained.View full abstractDownload PDF (7847K) -
Hisamichi Kimura, Akihisa Inoue, Kenichiro Sasamori, Akira Kato, Terua ...1999 Volume 46 Issue 12 Pages 1321-1326
Published: December 15, 1999
Released on J-STAGE: July 12, 2010
JOURNAL OPEN ACCESSPowder metallurgy (P/M) alloys of Al-3 at%Fe-3 at%M-2 at%Ti (M=V, Cr, Mn) were prepared by extruding gas atomized powders with the sizes smaller than 75μm at 673 K. The constituent structure was quasicrystalline (Q.C.)+Al+Al23Ti9+Al13Fe4 for the M=V alloy, Q.C.+Al+Al23Ti9 for the M=Cr alloy and Q.C.+Al+Al23Ti9 for the M=Mn alloy. The Q.C. particles in the P/M Al-3 at%Fe-3 at%M-2 at%Ti (M=Cr, Mn) alloys have an icosahedral structure and their particle sizes are 300 to 900 run. The analysis by an energy dispersive x-ray spectrometer indicates that the compositions of Q.C. particles of the P/M Al-3 at%Fe-3 at%M-2 at%Ti (M=Cr, Mn) alloys are Al-6.1 at%Fe-6.8 at%Cr-2.4 at%Ti and Al-7.8 at%Fe-8.0 at%Mn-1.4 at%Ti, respectively. The volume fraction of the Q.C. particles decreases in the order of M=Cr>Mn>V in the P/M Al-3 at%Fe-3 at%M-2 at%Ti (M=V, Cr, Mn) alloys. The ultimate tensile strength (σurs), 0.2% proof strength (σ0.2), plastic elongation (εp), Young's modules (E) and Vickers hardness (Hv) of the P/M Al-3 at%Fe-3 at%M-2 at%Ti (M=V, Cr, Mn) alloys are 494 MPa, 407 MPa, 5.5%, 87 GPa, 159 for the M=V alloy, 581 MPa, 488 MPa, 3.3 %, 85 GPa, 191 for the M=Cr alloy, 584 MPa, 491 MPa, 2.7%, 89 GPa, 191 for the M=Mn alloy, respectively, at room temperature. The σvrs, σ0.2. and εp of the P/M Al-3 at%Fe-3 at%M-2 at%Ti (M=V, Cr, Mn) alloys are 250 MPa, 221 MPa and 8.9% for the M=V alloy, 302 MPa, 277 MPa and 5.6 % for the M=Cr alloy, and 238 MPa, 190 MPa, 8.8% for the M=Mn alloy, respectively, after holding for 100 h at 573K.View full abstractDownload PDF (2172K) -
Hisamichi Kimura, Akihisa Inoue, Kenichiro Sasamori1999 Volume 46 Issue 12 Pages 1327-1333
Published: December 15, 1999
Released on J-STAGE: May 22, 2009
JOURNAL OPEN ACCESSWe examined the structure in rapidly solidified Al-M (M=Mo, V, Cr, Mn, Fe, Co, Ni) binary alloys and noticed that a quasicrystalline phase is formed in the M=V, Cr and Mn alloys. The fcc-Al plus quasicrystalline structure was formed in the range of 4 to 16 at%Cr or 6 to 23 at%Mn, and having almost single quasicrystalline phase in the vicinity of 14.0 at%V, 15.4 at%Cr or 22.5 at%Mn. The Vickers hardness values of the Al86V14, Al84.6Cr15.4 and Al77.5Mn22.5 alloys with having almost single quasicrystalline phase were 735, 1010 and 710, respectively and the grain size of the quasicrystalline phase was 200, 450 and 650 nm, respectively. The addition of Ce in the Al-Cr binary alloys was effective for the extension of the solute concentration range of quasicrystalline phase to a lower solute concentration range. The particle size and volume fraction of the quasicrystalline phase in the A194Cr5Ce1 alloy were about 200 nm and 70 %, respectively and the tensile fracture strength (σf) was 650 MPa. The σf increased to 1080 MPa for the Al95Cr3Ce1Co1 alloy in which the particle size and volume fraction were about 50 nm and 70 %, respectively. The σf of the Al94V4Fe2 alloy was 1390 MPa and the particle size and volume fraction were about 13 nm and 50 %, respectively. Similarly, the of of the Al93Ti4Fe3 alloy was 1320 MPa and the particle size and volume fraction were about 12 nm and 30 %, respectively. In aluminum alloys containing nanoscale quasicrystalline and amorphous particles, the 0.2 % proof stress (σ0.2) increased with decreasing particle size up to about 25 nm. When the particle size decreased further to was less than about 25 nm, the σ0.2 decreased with decreasing particle size. The transition from Hall-Petch relation to inverse Hall-Petch relation was recognized to occur in the vicinity of 25 nm.View full abstractDownload PDF (2450K) -
Kimihiro Ozaki, Keizo Kobayashi, Akihiro Matsumoto, Akira Sugiyama, To ...1999 Volume 46 Issue 12 Pages 1334-1338
Published: December 15, 1999
Released on J-STAGE: May 22, 2009
JOURNAL OPEN ACCESSThe influence of composition and mechanically grinding (MG) on the heat characteristic and the quasicrystalline size in rapidly solidified Al-Cr-Si alloy is investigated. The size of quasicrystal is quantitatively measured with Atomic Force Microscope (AFM). Al74Cr20Si6, Al77Cr13Si10 and Al90Cr6Si4 alloy ribbons are prepared by single roll quenching. Al74Cr20Si6 alloy consists of quasicrystalline single phase, and others consist of Al phase and quasicrystalline phase. The crystallization temperature of the quasicrystal becomes lower with increasing Al content in alloy. The size of quasicrystal in Al74Cr20Si6 ribbon is larger than 500nm, and the average sizes of quasicrystal in Al77Cr13Si10 ribbon and Al90Cr6Si4 ribbon are 177 and 89nm, respectively. The reduction in the crystallization temperature relates to the size of quasicrystal. By mechanically grinding the crystallization temperature and the size of quasicrystal become lower and smaller. The average size of quasicrystal in mechanically ground Al90Cr6Si4 for 1800s is 76nm. The crystallization temperature decreases because of breaking the quasicrystal in MG.View full abstractDownload PDF (4732K) -
1999 Volume 46 Issue 12 Pages 1341
Published: 1999
Released on J-STAGE: May 22, 2009
JOURNAL OPEN ACCESSDownload PDF (32K)
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