No Poly crazing or cracking when doing a proper job................................
Quote:
Originally Posted by
eyes4u
I have been using trivex or 1.67 over poly lately...I find alot of the poly materials split and crack at drill points and on semi rimless where the nylon line starts and a metal frame begins the poly wil chip or split internally. I like the thinness of the 1.67 material and thats its aspheric
There are ways to get around it. No Poly crazing or cracking when doing a proper job................................
One other reason why Poly can crack..............................
Mechanical Properties of Multilayer Coatings on Polycarbonates
Prepared by PECVD
V. Buršíková1, L. Zajíčková1, J. Buršík2 and J. Janča1
1Department of Physical Electronics, Faculty of Science, Masaryk University,
Kotlářská 2, 611 37 Brno, Czech Republic, e-mail: vilmab@physics.muni.cz
2Institute of Physics of Materials, Academy of Sciences of the CR, Žižkova 22, 616 62 Brno, Czech Republic
Abstract
In the present work, several different types of intermediate layers between the polycarbonate (PC) substrate
and the plasma deposited hard SiO
x-like protective coatings have been studied and their influence on the
mechanical properties of the whole coating/substrate system has been compared. By the help of an optimized
fracture resistant intermediate multilayer system and the hard SiO
x-like protective coating the original PC
surface hardness (~0.2 GPa) was increased by almost two orders of magnitude (5-9 GPa).
Read whole report: http://134.147.148.178/ispcdocs/ispc...Papers/845.pdf