Beake, Ben D. , Isern, Luis , Bhattacharyya, Debabrata , ENDRINO ARMENTEROS, JOSÉ LUIS, Lawson, Ken , Walker, Trevor
Si
Wear
Article
Científica
3.892
1.205
15/12/2020
000595091400003
2-s2.0-85092744542
Optimising the mechanical properties of optical coatings to improve their durability will be critical if they are to be used successfully in harsh environments where they may be subject to degradation by mechanical contact. In this study zirconia, zirconia-alumina duplex and alumina experimental coatings were deposited on soda lime and borosilicate glass and their resistance to repetitive impact under different experimental conditions evaluated in nanoand micro-scale impact tests. The influence of changing probe geometry (sharp and blunt contacts) and applied load on the deformation was studied. Spheroconical indenters were found to be more suitable to study the load sensitivity of the impact response than sharp cube corner indenters. Increased resistance to plastic deformation in the coating-substrate system (H-3/E-2) proved detrimental to the damage tolerance to the repetitive nanoand micro-impact tests. To compare the deformation behaviour in nano-impact and nano-scratch, tests were performed using the same spheroconical probe, revealing cracking and blistering of the glass substrate in both types of test. The change in probe depth after the first impact was found to be a very useful metric to effectively compare the evolution of surface damage on continued impact in nanoand micro-impact tests at different applied load and probe geometry.
Surface analysis; PVD coatings; Fracture behaviour; Impact wear; Optical; Wear testing