Acicular Interlocking Microstructures

Drawing on the experience of the textile industry, they had to be woven together in multiple layers. The mechanical properties of the composite structure are therefore highly anisotropic. 

In recent developments of long-fiber-reinforced composites described by Prewo (1989), the toughness was increased to more than 8 MPa m -. In this case, however, the fiber pull-out properties from the matrix contributed to the increase in the toughness of the material. 

After the initial developments in the 1950s and 1960s, attempts were made to increase the strength of glass-ceramics by surface compression. The materials, however, were difficult to realize practically. In response to these problems, Beall (1991) developed a new generation of tough glass-ceramics, the microstructure of which is discussed in this section. 

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