Design, superhard materials

Veprek, S., Conventional and New Approaches Towards the Design of Novel Superhard Materials, Surf. Coat. Technol, Vol. 97,1997, pp. 15-22. 

S. Veprek, Conventional and new approaches towards the design of novel superhard materials. Surf. Coat. Technol. 97(1-3), 15-22 (1997)... 

As already discussed the practical hardness (and strength in general) of a material is determined by its microstructure. An appropriate design of the microstructure can easily result in an increase of the hardness by a factor of 4-7. The experimentally found superhardness of the ncM N/aSi3N4 and ncTiN/BN nanocomposites of 5000-7000 kgmm corresponds to an increase by a factor of 2.5-4, rather in the lower range. Also the hardness of 10 000-13 000 kg mm which we often measure... 

Some theoretical aspects were discussed to show the generality of the principle for the design of superhard nanocomposites. The present review was complemented by a brief summary of the recent development in the field of heterostructures which represent another approach to the design of superhard nanostructured materials. 

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