title: Effect of thermal annealing in vacuum and in air on nanograin sizes in hard and superhard coatings Zr-Ti-Si-N.
abstract: Zr-Ti-Si-N coating had high thermal stability of phase composition and remained structure state under thermal annealing temperatures reached 1180 degrees C in vacuum and 830 degrees C in air. Effect of isochronous annealing on phase composition, structure, and stress state of Zr-Ti-Si-N-ion-plasma deposited coatings (nanocomposite coatings) was reported. Below 1000 degrees C annealing temperature in vacuum, changing of phase composition is determined by appearing of siliconitride crystallites (beta-Si3N4) with hexagonal crystalline lattice and by formation of ZrO2 oxide crystallites. Formation of the latter did not result in decay of solid solution (Zr, Ti)N but increased in it a specific content of Ti-component. Vacuum annealing increased sizes of solid solution nanocrystallites from (12 to 15) in as-deposited coatings to 25 nm after annealing temperature reached 1180 degrees C. One could also find macro- and microrelaxations, which were accompanied by formation of deformation defects, which values reached 15.5 vol.%. Under 530 degrees C annealing in vacuum or in air, nanocomposite coating hardness increased. When Ti and Si concentration increased and three phases nc-ZrN, (Zr, Ti)N-nc, and alpha-Si3N4 were formed, average hardness increased to 40.8 +/- 4 GPa. Annealing to 500 degrees C increased hardness and demonstrated lower spread in values H = 48 +/- 6 GPa and E = (456 +/- 78) GPa. Zr-Ti-Si-N coatings has high wear resistance and low friction coefficient in comparison at a temperature of 500 degrees C possess with coatings TiN, Ti-Si-N.
authors: Sumy State University, St.R-Korsakov 2, 40007 Sumy, Ukraine.
authors: A D
authors: AD
authors: Pogrebnjak
authors: A P
authors: AP
authors: Shpak
authors: V M
authors: VM
authors: Beresnev
authors: D A
authors: DA
authors: Kolesnikov
authors: Yu A
authors: YA
authors: Kunitskii
authors: O V
authors: OV
authors: Sobol
authors: V V
authors: VV
authors: Uglov
authors: F F
authors: FF
authors: Komarov
authors: A P
authors: AP
authors: Shypylenko
authors: N A
authors: NA
authors: Makhmudov
authors: A A
authors: AA
authors: Demyanenko
authors: V S
authors: VS
authors: Baidak
authors: V V
authors: VV
authors: Grudnitskii