Evaluation on Rotational Bending Fatigue Limits using Thermography
by Keisuke HAYABUSA, Hiroaki NAKAMOTO, Kazuaki INABA, & Kikuo KISHIMOTO
Simplified thermography-using methods are being developed for evaluating the fatigue limits of materials. By these methods, fatigue limits are determined as the load stress applying at the time of a surge in temperature, i.e. temperature changes due to stress amplitude increase on an objects under a cyclic load are measured. Although many such methods have been tested for evaluating tensional compression and bending loads on flat objects, there are almost no examples of actual cases where they had been used for evaluating the rotational bending of shafts. A thorough study had been made on the effectiveness of a thermography-using method for evaluating the rotational bending fatigue of a shaft, including the time dependency of temperature changes and the determination of an objective fatigue limit.
Fatigue limit, Fatigue testing, Rotational bending, Thermography, Dissipated energy, Lock-in, Least squares method, S-N curve, Steady state, Inflection poin
Copper Electroplating of High Aspect Ratio Through-silicon Via for 3D Packaging using an UFP Tool
by Mizuki NAGAI, Yusuke TAMARI, Shingo YASUDA, Masashi SHIMOYAMA, Nobutoshi SAITO, & Fumio KURIYAMA
A new electroplating technique has been developed for the EBARA UFP series, a highly productive and reliable wafer electroplating system series. This series, mainly applied for soldering and bumping, as well as for distribution lines, is in high demand by various Asian and domestic leading-edge semiconductor manufacturers. Ebara has gone a step further by developing a new electroplating technique which makes this series capable of copper filling of high aspect ratio TSV (Through-Silicon Via) for 3D packaging. The following introduces and discusses this new technique.
Copper plating, Electroplating, 3D packaging, Through silicon via, Plating tool, Filling, Additives, Agitation, Flow rate
Chilled Water Feed System operable under Large Temperature Differences and equipped with High-efficiency Centrifugal Refrigerating Machine
by Sadayoshi TAKAHASHI, Takanori NAKAMURA, & Shinya ISHIHARA
A chilled water feed system, operable under large temperature differences and equipped with our newly developed high-efficiency, inverter-driven, centrifugal refrigerating machine, has been delivered to a gold ore mine. This system was designed to handle a 20℃ temperature difference at system inlet (25℃) and outlet (5℃), and a refrigeration machine temperature difference of 12℃. This setup enables a refrigeration machine COP = 6.3 and system COP = 5.05. Under maximum load during the field test, a COP of 5.76 was attained. The chilled water temperature can also be controlled to minimize environmental impact in the mine. This system makes full use of the high-efficiency, inverter-driven, centrifugal refrigeration characteristics and is capable of reducing CO2 emission during partial load and load fluctuation conditions.
High-efficiency, Centrifugal refrigerating machine, Chilled water feed system operable under large temperature differences, Hishikari Mine, In-mine reduction of environmental inpact, Pump electric power reduction, Coefficient of performance, System efficiency, Partial load, CO2 reduction