Abstract: Cu-Be alloy (C17200) rod having diameter of 23.5mm was produced by a vacuum
continuous casting method at furnace temperature range of from 1240°C to 1260°C with casting
speed range of from 35mm/min to 103mm/min. When the furnace temperature was 1240°C and
1250°C, Cu-Be alloy rod without fracture could successfully produced at high casting speed of
103mm/min. However, when the furnace temperature was 1260°C, the breakout occurred at casting
speed faster than 78mm/min. Surface roughness (Ra) increased with increasing not only a furnace
temperature but also a casting speed.
Abstract: Fatigue strength of Al5083-O FSW joints was evaluated in the relation of the FSW
conditions. Static strength of the joints in a range of FSW conditions was the same as that of base
metal. Because the fracture of the joints occurred at the base metal in the tensile tests. Therefore the
joint efficiency in tensile strength of joints with the FSW condition of tool rotation: 800 rpmwelding
speed: 100 mm/min (800-100), 800-200 and 500-100 are all hundred percent. However, the
fatigue strength of those joints with fine static strength varied very much. The joint efficiency for
fatigue strength varies from 75% for 500-100 to 31% for 800-200. Crack path in fatigue test was
always initiated at the center of back surface of FSW weld zone, and propagated through stir zone.
Crack growth rate measurement and fracture surface analysis resulted the difference of the joint
efficiency has a connection with the incomplete welding at back surface of joints.
Abstract: A static magnetic field and an alternating current are imposed on a metallic alloy during
solidification for a crystal alignment of the primary phase. A Sn-10%Pb is selected as a sample
because its primary phase is expected to have an anisotropic nature in magnetic susceptibility. In
the x-ray diffraction pattern of the sample solidified without the magnetic field, the first and second
highest peaks are (101) and (211) planes. On the other hand, those solidified with the magnetic field
are (200) and (220) planes which are magnetically preferred planes. That is, the primary phase
crystals in the sample solidified with the magnetic field are aligned to the specific direction.
Abstract: The effect of aging temperature and aging time on properties of Cu-3.2Ni-0.75Si-0.3Zn
alloy were studied. The alloys were isochronally or isothermally aged after solution treatment. The
cold rolling prior to the aging treatment was used to increase the precipitation rate .The microstructure
of the alloy was studied by means of transmission electron microscope (TEM). The results show that
the fine and dispersed precipitates are fully coherent with the Cu matrix and make the alloy possesses
higher hardness and conductivity after the alloy was solution at 1173K and then aged at different time.
The precipitates responsible for the age-hardening effect was Ni2Si.The transformation kinetics were
studied by analyzing the electrical resistance variation of the solution Cu-3.2Ni-0.75Si-0.3Zn alloy in
the process of aging.
Abstract: CaAl2O4:Eu2+ with high brightness and long persistent luminescence were prepared by solid state
reaction method. The phosphor compositions with varying Eu2+ were investigated by powder X-ray
diffractometer (XRD), SEM, TEM, photoluminescence excitation and emission spectra. Broad band UV
excited luminescence of the CaAl2O4:Eu2+ was observed in the blue region (λmax = 440 nm) due to transitions
from the 4f65d1 to the 4f7 configuration of the Eu2+ ion. The particle size also plays a role deciding the
luminescence characteristics of these phosphors. The decay time of the persistence indicated that the
persistent luminescence phosphor has bright phosphorescence and maintains a long duration.
Abstract: The influences of hydrogen absorption on the Curie temperature TC and the isothermal
magnetic entropy change for La0.5Pr0.5(Fe0.88Si0.12)13 have been investigated, because the
magnetocaloric effects have been confirmed to be enhanced after a partial substitution of Pr for La
in La(Fe0.88Si0.12)13. The value of TC for La0.5Pr0.5(Fe0.88Si0.12)13Hy increases from 185 to 324 K
with increasing y from 0 to 1.6. The maximum value of the isothermal magnetic entropy change
MAX is slightly decreased by hydrogen absorption. However, ,Sm
MAX = -26 J/kg K in a
magnetic field change of 5 T for La0.5Pr0.5(Fe0.88Si0.12)13H1.6 is still larger than the value of -23 J / kg
K for La(Fe0.88Si0.12)13H1.5 having almost the same value of TC. Consequently, ,Sm
MAX of the
La0.5Pr0.5(Fe0.88Si0.12)13Hy is larger than that of La(Fe0.88Si0.12)13Hy in a wide temperature range
covering room temperature.
Abstract: The anodic aluminum oxide (AAO) templates were prepared by a two step anodization
process in a mixture phosphoric acid, sulfuric acid and chromic acid and oxalic acid. The pore of
anodic aluminum oxide templates were hexagonal arranged pore domains. Oredred Nickel
nanowires were prepared in this porous anodic aluminum oxide templates from Watt solution and
additives by an electrodeposition. The diameter of Nickel nanowires in the array were about 80 nm
and the length is about 800 nm with the aspect ratio of about 10. The ordered Nickel nanowires
were characterized by X-ray diffractometer, scanning electron microscopy and magnetometer.
Abstract: In this study, we have investigated a texture and microstructure of gold bonding wire by
transmission electron microscope, X-ray diffraction and electron back scatter diffraction according to
process parameters, such as casting, drawing and annealing processes. The gold was cast into 7mm
diameter rods by vertical continuous casting technique, the cast rods were drawn to a final wire size of
25μm, and then the fine wires were annealed. A unidirectional solidification structure having <100>
fiber texture of cast rod was strongly developed depending on casting route and speed. In the sample
with unidirectional microstructure developed in partial it is found that dislocation substructure with
nano-size appeared to display a characteristic feature, while no dislocation substructure is seen in the
sample with complete unidirectional microstructure. Interface stability between solid and liquid may
be responsible for this difference in dislocation substructure. With decreasing casting speed <100>
fiber component became weak. Initial texture plays important role on development of <111> fiber
texture at drawing and final annealing stages. On the basis of results obtained it is suggested that both
the initial texture are important in controlling the texture of gold bonding wire.