Yoon K.J.,Boston University |
Ye G.,BTU International Inc. |
Gopalan S.,Boston University |
Pal U.B.,Boston University
Journal of Fuel Cell Science and Technology | Year: 2010
The anode-supported planar solid oxide fuel cell (SOFC) was fabricated by a costeffective single step cofiring process using high shear compaction (HSC)™ anode substrate. The HSC™ process is a novel ceramic tape fabrication technique, which offers advantages in low-cost and high-volume production of the anode substrates over the conventional tape forming processes. The cell was comprised of a porous HSC™ Ni + 8 mol % yttria-stabilized zirconia (YSZ) anode substrate, a porous Ni + YSZ anode barrier layer, a porous and fine-grained Ni + YSZ anode active layer, a dense YSZ electrolyte, a porous and fine-grained Ca-doped LaMnO3 (LCM) + YSZ composite cathode active layer, and a porous LCM cathode current collector layer. The fabrication process involved wet powder spraying of the anode barrier layer over the HSC™ anode substrate followed by screen-printing of the remaining component layers. The cell was then cofired at 1340° for 2 h. The microstructure and the open circuit voltage of the cell confirmed that the cell was crack-free and leak-tight. The cofired cell showed a stable and acceptable electrochemical performance at 800° under humidified hydrogen (3-60% H2O) as fuel and air as oxidant. The anode active layer with finer and less porous microstructure increased the triple phase boundary length and improved cell performance under conditions that simulated higher fuel utilization. The material system and fabrication process presented in this work offers great advantage in low-cost and high-volume production of SOFCs, and it can be the basis for scale-up and successful commercialization of the SOFC technology. Copyright © 2010 by ASME.
Dimock F.,BTU International Inc.
Printed Circuit Design and Fab/Circuits Assembly | Year: 2011
A proper understanding of factors that affect the transfer of thermal energy from the heater in a convection oven to the board is necessary to study the practical thermal profile in a dual-lane, dual-speed reflow oven. When running a new board in a single-lane, the profile is adjusted by modifying the set points or the belt speed to obtain the correct profile. A baseline eutectic recipe that produces a standard ramp-soak-spike profile with the 360 g board at 45 1PM is the first step in the trial. The results show that at the lower belt speeds, the difference between boards is about 7°C, and at the faster speeds, it was close to 13°C. KIC Explorer predicted peak temperatures that are within 2°C to 3°C of what was actually measured, in addition to obtaining the original profiles for the trial.
BTU International Inc. | Date: 2013-10-07
A furnace system for thermal processing of products and materials is disclosed which is particularly useful in processing touch screens for computer tablets and silicon wafers employed in fabricating solar cells. The system employs a hybrid of microwave and radiant heating of workpieces to provide controlled heating of the workpieces. A plurality of susceptors are disposed a furnace chamber. A plurality of microwave sources are arranged to provide microwave radiation in the chamber to uniformly heat workpieces in the chamber and to provide uniform heating of the susceptors. The susceptors are effective upon microwave heating by the microwave sources to provide uniform radiant heating of the workpieces in the chamber.
BTU International Inc. | Date: 2015-06-11
A high temperature conveyor belt is provided having a non-metallic conveying surface which will not scratch, abrade or otherwise mar the surface of a product being carried on the belt through a furnace and which will not contaminate the product. In one embodiment, the conveyor comprises a high temperature fabric belt attached to a metal belt which may be a conventional woven metal conveyor belt. In another embodiment, the conveyor is composed of a non-metallic high temperature strand which is woven or threaded through a metal belt to provide a non-metallic conveying surface. In a further embodiment, the non-metallic product support elements are coupled to roller chains at each side of the furnace chamber and which are cooperative with a drive mechanism to transport the conveyor through the furnace. The roller chains can be located outside of the furnace chamber to avoid exposure to the high temperature of the furnace chamber.
BTU International Inc. | Date: 2015-02-17
The present invention comprises a thermal reactor and method for thermal processing of particles carried in a gas stream through the reactor. The reactor system can operate in a continuous manner for the thermal processing of particles flowing through the reactor. The system in one embodiment employs a hybrid of microwave and radiant heating of the particles. In other embodiments, only microwave heating is employed, or only radiant heating is employed.