Jump to main content
Jump to site search
PLANNED MAINTENANCE Close the message box

Scheduled maintenance work on Wednesday 22nd May 2019 from 11:00 AM to 1:00 PM (GMT).

During this time our website performance may be temporarily affected. We apologise for any inconvenience this might cause and thank you for your patience.

Issue 16, 2014
Previous Article Next Article

Enhanced stability of hafnia based coatings in a hot gas environment

Author affiliations


Yttria stabilized hafnia (YSH) coatings have been fabricated by magnetron sputtering, a physical vapor deposition (PVD) method. Coatings of a mixed composition of hafnia (HfO2) and zirconia (ZrO2) (YSHZ) stabilized by yttria (Y2O3) were also fabricated in order to compare and contrast the resulting properties. The composition of the material was varied by varying the ratio of HfO2 and ZrO2 (4 : 1, 2 : 1, 1 : 1, 1 : 2 and 1 : 4) while keeping the Y2O3 stabilizer content constant at 7.5 mol%. Thermal and chemical stability along with the durability of the YSH and YSHZ coatings were evaluated by exposing the coatings to hot gases in a combustor rig. A nanoindentation technique was used to evaluate the mechanical properties. A diamond tipped, sharp nanoindenter with known geometry and mechanical properties was forced into the sample while both the force and indentation depth were recorded. Hardness (H) and Young's modulus were estimated for the YSH and YSHZ coatings. Atomic force microscopy was utilized to provide imagery of the indentation area on the sample surface. Residual stress analysis was performed using X-ray diffraction (XRD). The results from nano-indentation indicate that the YSH sample possesses values of hardness and Young's modulus as high as 18 GPa and 220 GPa, respectively. The residual stress estimated using XRD indicates very high compressive stress within the coatings. The stability and durability tests demonstrate the enhanced stability of YSH coatings in a hot gas environment created by burning natural gas with oxygen.

Graphical abstract: Enhanced stability of hafnia based coatings in a hot gas environment

Back to tab navigation

Publication details

The article was received on 04 Sep 2013, accepted on 26 Nov 2013 and first published on 26 Nov 2013

Article type: Paper
DOI: 10.1039/C3RA44882G
RSC Adv., 2014,4, 8224-8229

  •   Request permissions

    Enhanced stability of hafnia based coatings in a hot gas environment

    M. Noor-A-Alam, S. K. Gullapalli, E. J. Rubio, A. R. Choudhuri and C. V. Ramana, RSC Adv., 2014, 4, 8224
    DOI: 10.1039/C3RA44882G

Search articles by author