Metallurgical study of thermionic converters

This paper describes some of the observations made as a result of the test of 180 thermionic converters and of the postmortem metallographic examination of approximately 50 converters. The causes and effects of converter abnormal performance are related to the results of the metallographic examinations. The materials and fabrication methods utilized in converter construction are discussed together with areas of possible improvement, the goal being long-life converters capable of reliable performance.