Metal-supported oxide cells (MSCs) are considered as the third-generation solid oxide cells (SOCs) succeeding electrolyte-supported (first generation) and anode-supported (second generation) cells, which have gained much attention and progress in the past decade. The use of metal supports and advanced technical methods (such as infiltrated electrodes) has vastly improved cell performance, especially with its rapid startup ability and power density, showing a significant decrease in raw materials cost. However, new degradation mechanisms appeared, limiting the further improvement of the performance and lifetime. This review encapsulates the degradation mechanisms and countermeasures in the field of MSCs, reviewing the challenges and recommendations for future development.

A new three-color infrared radiation pyrometer using an optical fiber is developed for measuring cutting temperature in high speed machining by small ball end mill. The high speed air spindle unit is adopted to the ordinary milling machine so that the maximum spindle revolution of 40000rpm is attainable. The ball radius of the carbide cutter is 3mm and the side cutting of carbon steel with ballnose is executed without cutting fluid. Cutting temperature distribution along the ball-nosed cutting-edge is measured. The influences of spindle rotational speed, radial depth of cut and feed per tooth on the temperature distribution at the flank face are examined. The maximum temperature of peripheral cutting edge about 700°C is obtained even at the rotation angle of 180° after cutting, and it drops along the ballnose toward the ball tip. Relatively large temperature gradient arises along the ball cutting-edge at higher spindle revolution because cutting speed depends on the local tool radius. Depth of cut and feed per tooth, at the same time, affect the overall temperature at the ball cutting edges. The cooling characteristics in air cutting reveals that the temperature difference during one cycle of intermittent cutting increases as spindle speed decreases. The relationship between the peripheral cutting speed and the tool temperature varies from tool shank to ball tip because the interactions between cutting edge and workpiece change along the ballnose.