Progress of Precision Engineering and Nano Technology
Vol. 339
Vol. 339
High-Performance Ceramics IV
Vols. 336-338
Vols. 336-338
Advances in Composite Materials and Structures
Vols. 334-335
Vols. 334-335
Functional Gradient Ceramics, and Thermal Barriers
Vol. 333
Vol. 333
Bioceramics 19
Vols. 330-332
Vols. 330-332
Advances in Abrasive Technology IX
Vol. 329
Vol. 329
Experimental Mechanics in Nano and Biotechnology
Vols. 326-328
Vols. 326-328
Fracture and Damage Mechanics V
Vols. 324-325
Vols. 324-325
Advanced Nondestructive Evaluation I
Vols. 321-323
Vols. 321-323
Electroceramics in Japan IX
Vol. 320
Vol. 320
High Damping Materials II
Vol. 319
Vol. 319
The Science of Engineering Ceramics III
Vols. 317-318
Vols. 317-318
Advances in Machining & Manufacturing Technology VIII
Vols. 315-316
Vols. 315-316
Experimental Mechanics in Nano and Biotechnology
Volumes 326-328
Paper Title Page
Abstract: As the application technique for glass bottle’s recycling system, a new “Cullet”
generation method by using underwater shock wave was proposed. This small fragmentation
technique of glass bottles has a lot of excellent advantages such as the simplification of process by
simultaneous cleaning and crushing operation, the high collect rate of “Cullet” and so on. In this
study, the relation between of the explosive conditions and “Cullet” sizes were clarified and the
high speed fracture process of glass bottle was observed by framing photograph of high speed
image converter.
1551
Abstract: The spacer grid assembly, which is an interconnected array of slotted grid straps and
welded at the intersections to form an egg crate structure, is one of the main structural components
of the nuclear fuel assembly of a Pressurized light Water Reactor (PWR). The spacer grid assembly
supports and aligns the fuel rods, guides the fuel assemblies past each other during handling and, if
needed, sustains lateral seismic loads. The ability of the spacer grid assembly to resist the lateral
loads is usually characterized in terms of its dynamic and static crush strengths, which are acquired
from tests. In this study, dynamic buckling tests and finite element analyses on spacer grid assembly
specimens are carried out. Comparisons show that the analysis results are in good agreement with
the test results to within an 8 % difference range. Therefore, we could predict the crush strength of a
spacer grid assembly in advance before performing the dynamic buckling test.
1555
Abstract: Present investigation were carried out to study photoelastically the stress distributions in
a simply supported beam with over- hangs subjected to a low velocity central- and quarter- spanimpact
loadings by light strikers keeping beam/ striker weight ratio constant (2.675), and then
comparing the results so obtained with those in similar simply supported beams made of other
materials subjected to central- impact loadings from an analysis of dynamic strain gauge
data. Interesting new findings were obtained from the results of the present investigation and also
from results reported in the literature in this respect.
Introduction.
In modern times dynamic stress analysis is becoming increasingly important for various
engineering applications. Although significant amount of insight in these respects have been
developed, the subject being rather intricate would continue to attract of more research workers in
future.
A beam is a common structural element, and in several applications, simply supported beams
with over- hang are employed in practice. Transverse and longitudinal bridge girders and chassis
of rails- and road- wagons are some of the typical applications of the same. Here, photoelastic
technique was employed to determine dynamic stress distributions in a model simply supported
beam with over- hang.
1559
Abstract: Structural failure of fibre-reinforced polymers (FRP) caused by impact is an important factor in product development
for the aircraft industry. Therefore it is necessary to obtain knowledge of the mechanisms and of the material loading
during and shortly after an impact load. On account of this a Finite-Element-Model was developed with the goal to
deduce design rules for impact tolerant composite materials.
To verify and validate the Finite-Element-Model it is essential to have information of the state of stress on the surface
of the FRP shortly after the impact. An impact test device was developed at the University of Bremen. The time
variable, stress and strain conditions in composite plates are measured using photoelastic technique, strain gauges and
holographic interferometry.
1563
Abstract: Attempts have been made to improve the impact resistance of biodegradable
thermoplastic polymer, PLA. A ductile biodegradable polymer, PCL, has been used to improve such
property of PLA by using blending technique. Details of the impact fracture properties and
mechanisms of PLA/PCL blends, however, have not fully been understood yet. Recently, it was also
found that LTI can improve the immiscibility between PLA and PCL. In this study, PLA/PCL and
PLA/PCL/LTI blends were prepared, and their impact fracture toughness values were measuredto
assess the effect of PCL content and LTI addition on the impact resistance. Fracture mechanisms of
the polymer blends were also characterized by scanning electron microscopy.
1569
Abstract: Dynamic response and fracture of high strength boride/alumina ceramic composite were
investigated by split Hopkinson pressure bar (SHPB) experiment in this paper. The compressive
stress–strain curves and dynamic compression strength of the composites were tested. The surface’s
microstructure of fractured composites were examined by using scanning electron microscope
(SEM) to investigate the fracture mechanism. The results show that boride/alumina has high
dynamic compressive strength and high Young’s modulus. The main fracture mode of the material is
the fracture of the ceramic grains. The micro-voids and flaws, generated during the sintering and
manufacturing of material and mechanical process of specimen, decrease the strength of the material
because they provide the source of crack expansion when the material undergoes the dynamic
loadings.
1573
Abstract: This paper presents a modified Split Hopkinson Pressure Bar(SHPB) technique to obtain
compressive stress-strain data for a rubber material. An experimental technique with a modified the
conventional SHPB has been developed for measuring the compressive stress strain responses of
materials with low mechanical impedance and low compressive strengths such as a rubber. This
paper uses an aluminum pressure bar to achieve a closer impedance match between the pressure bar
and the specimen materials. In addition, a pulse shaper is utilized to lengthen the rising time of the
incident pulse to ensure stress equilibrium and homogeneous deformation of a rubber. It is found
that the modified technique can determine the dynamic deformation behavior of rubbers under
various conditions such as high strain rate and low temperature effects.
1577
Abstract: Results of tests using two kinds of nylon reinforced concrete samples are described . In
order to deal with the heterogeneous effects of samples resulted from large particles which range
from7mm to10mm in diameters, a SPH bar which is 74mm in diameter is used. There seems
something new and difficult in the method of testing the concrete’s dynamic compressive responses.
The results show that there are obvious strain rate effects in both the two kinds of samples , and the
failure strength increases with the increasing of the strain rate.
1581
Abstract: Hard disk drives (HDD) are now the most important means of information storage, and
they continue to be made smaller in size, higher in capacity, and lower in cost. The dynamic
performance of an HDD has been an increasingly important consideration for its design, as we
move forward toward its consumer applications. The dynamic properties of the head arm assembly
(HAA) of a micro-drive were investigated using both experimental and numerical techniques. A
finite element model for studying the dynamic property of the HAA was created and modified
according to the experimental results. Good correlation between the experimental results and those
by finite element simulation was achieved.
1585
Abstract: Optical disk drive (ODD) technology has been rapidly improved to treat the gradually
increasing data storage and data transfer rate. The rotational velocity of the disk must be increased
to deal with huge data. However the increased rotational velocity can inherently cause unwanted
phenomena such as noise and vibration. The major noise sources of the ODD system are
mechanical vibration which generated inside ODD and turbulent aerodynamic noise which
generated by the viscous flow rotation. In this study, practical experimental tests of driving noise
for various optical disk drives have been performed using 1/2” microphone noise measurement
system. Sound insulation case with absorbing materials for the present experimental tests is
designed and constructed in order to minimize the effects of disturbance. Several commercial ODD
models by different manufacturers are practically considered in the present experiments and
compared for realistic driving conditions. It is shown that sound noise level, average data transfer
rate and operating RPM seems to be somewhat different for the ODD models with same proposed
speed by different manufacturers. Moreover, driving sound noise level can be largely affected by
both tray shape and driving speed even for the same apparent data transfer rate.
1589