Age hardening of PACVD TiBN thin films

This study demonstrates that plasma assisted chemical vapor deposited TiBN films, containing 17.4 at.% B, show a supersaturated NaCl-structured solid solution where B substitutes N. During annealing, hexagonal close-packed TiB2 precipitates form across B-rich domains, causing an increase in hardness at elevated temperatures. The findings are corroborated by ab initio calculations and additional investigations on TiN films.