Creep ductile ceramics

RT are considered in terms of their high-temperature performances, specifically under creep conditions. In Sect. 5.2.2, MgO was singled out as an example of a low-temperature ductile ceramic (see Figs. 5.3 and 5.4). Of further interest is RT ductile SrTiOa, which is one of many studied ceramics, due to its interesting and unique features (Fig. 6.24). 

Liao, T.W., Flexural strength of creep feed ground ceramics general pattern, ductile-brittle transition and MLP modeling. International Journal cf Machining Tools Manufacturing, 1998, 38(4), 257-275. 

Few polymers are thermally stable in comparison to the metals and ceramics. Even the most stable polymers like polyimides, or poly(ether ether ketone) (known as PEEK) are degraded by thermal exposure to above about 300 °C. The chemical degradation can not be decreased through the reinforcement of polymer. However, the strength deterioration and creep or visco-elastic deformation can be delayed by the fibre reinforcement. Moreover, polymers have very low mechanical strength and stiffness in bulk form. Except few plastics, the weakest plastics tend to be ductile but the strongest tend to be brittle like metals. Traditionally, polymers are insulators... 

Most simply and generally defined, creep is time-dependent deformation under constant stress . Even though creep may occur at relatively moderate temperatures, most ceramics are intended for use at high temperatures, where they are ductile. For ceramics with low-temperature ductility, creep may occur at 0.5 T or even at lower temperatures. The term defined below, indicating homologous... 

Creep in Brittle Ceramics (Ductile at High Temperature Where Deformation is Possible)... 

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