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Do you remember the oil shortages and gas lines of the 1970s, and the automotive emissions legislation that was enacted around the same time? Back then, it was clear that the world needed a high efficiency, multi-fuel, low pollution engine, and it was believed that the most promising way to get there was the small gas turbine (GT) engine.
"Ceramic" Engines
Small GT engines as they existed then were not very efficient. The most direct and lowest cost way to boost the efficiency of small GTs was to run them at very high temperatures (-1300C-1350oC) without cooling. Since sustained operation at 1300C or higher was not possible for superalloys, ceramics became the only option.
Fortunately, during the 1960s and 1970s major advances in high strength, low thermal expansion, thermal shock resistant ceramics (principally, silicon nitride and silicon carbide) were achieved, which made the use of highly stressed structural ceramics a realistic goal. Concurrently, computer based probabilistic design methodologies specifically tailored for brittle materials were refined and demonstrated.
These advances were mainly achieved by government support of research efforts at industrial laboratories in the United Kingdom, the U.S., Germany and Japan. Along with the interest in ceramic GTs, in the mid-1970s it became apparent that ceramic materials could facilitate high-efficiency, low-heat rejection diesel...