Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
(a) Crack initiation map and (b) failure map for flat quartz glass on polymer bilayers subject to cyclic indentation with a tungsten carbide sphere of radius r = 1.6 mm, in water. Glass layer thickness d = 1 mm. Oi and Ii indicate outer and inner cone crack initiation respectively, Ri indicates radial crack initiation. Of and If indicate outer and inner cone failures respectively. Arrow in (b) indicates run out.
