Samstag, 23. Oktober 2010
Shock resistance of Surface Coatings
This picture shows the zones of failure in an impact situation on coated surfaces.
In the peripheral zone there are the well-known bending-cracks, caused by the stretching of the substrate layer during the plastical deformation caused by the indenter.
In the central zone, the coating material cracks cohesively, thus causing irregular crack structures. This zone is especially large for brittle coating materials, such as (Di-)Chrome Nitride.
The zone in between shows failure of both types mentioned above.
To clear things up: this is sort of the things that make your saws, knifes and razors blunt.
Topic of research is to develop coatings that are very resistant against this kind of wear, as well as against abrasive wear, to keep the perfect quality of the surface for a longer time, thus keeping knifes sharp much longer.
I do really hope to enlighten things a bit. Comment on this, if you like.
Also, tell my your criticism,
what kind of topics would you like me to talk about next time?