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BACKGROUND - Applications
Mention ceramics and for the most part conventional thoughts turn to pottery and/or white wares (china). The history of ceramics can be traced back over 10,000 years, and yet these materials are providing the means to overcome technical barriers in a number of present day applications. By and large today’s advanced ceramics bear little functional resemblance to their origins. Their robust mechanical, thermal and electrical properties have opened up new vistas of development opportunities for manufacturers in a wide range of industries.
In micro-electro-mechanical systems (MEMS) ceramics are used as microturbines, pressure sensors, and thin film membranes. Moreover, oxygen ion-conducting ceramic membranes are being investigated world-wide for applications in solid oxide fuel cells, oxygen separators and catalytic membrane reactors. Several key economic/technical issues that have driven interest in advanced ceramics over the past 25 years are energy efficiency and reduced environmental emissions. From a design engineer’s perspective, advanced ceramics exhibit attractive high strength properties at service temperatures that are well beyond use temperatures of conventional ductile materials. Relative to the power generation industry and commercial aviation elevated service temperatures will improve fuel efficiency and promote more complete combustion. In advanced diesel and turbine engine applications ceramic components have already demonstrated functional abilities at temperatures over 1300 °C. This is well beyond the operational limits of most conventional metal alloys. The ability to analyze complex component geometries along with their attending boundary conditions through the use of finite element analysis has led to numerous technological breakthroughs over the past quarter century. Moreover, when commercial finite element codes such as ANSYS are combined with specialty algorithms such as CARES/Life and WeibPar, the resulting computational architecture provides the engineer with the requisite design tools relative to focused applications, such as the use of advanced ceramics. The resulting ability to analyze numerous design options can easily lead to productivity gains in that a near optimized design is evaluated before a prototypical component is ever fabricated.
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