PVD coating hardness 2 microstructure 2 20Cr2Ni4A 1 Al2O3 coating 1 History of engineering & technology 1 MAO coating 1 MAX phase 1 Ni-Fe-Co-P-CeO2 composite coating 1 PVD 1 Research & information: general 1 Ti2AlN 1 Vanadis 6 die steel 1 W-Cr-C coating 1 Zn-Al diffusion layer 1 aging mechanism 1 aluminum alloy AlMg6 1 aluminum foam 1 anodizing layers 1 apatite 1 boride-based cermet 1 carbon diffusion 1 carburization 1 carburizing 1 catalysis 1 cathodic protection 1 cavitation 1 chemical properties 1 coating 1 coating selection 1