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OsZr is Tetraauricupride structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Zr2+ is bonded in a body-centered cubic geometry to eight equivalent Os2- atoms. All Zr–Os bond lengths are 2.85 Å. Os2- is bonded in a body-centered cubic geometry to eight equivalent Zr2+ atoms.
ZrOS crystallizes in the cubic P2_13 space group. The structure is three-dimensional. Zr4+ is bonded in a 3-coordinate geometry to four equivalent S2- and three equivalent O2- atoms. There are one shorter (2.60 Å) and three longer (2.76 Å) Zr–S bond lengths. All Zr–O bond lengths are 2.11 Å. S2- is bonded in a 4-coordinate geometry to four equivalent Zr4+ and seven equivalent O2- atoms. There are a spread of S–O bond distances ranging from 2.99–3.25 Å. O2- is bonded in a trigonal planar geometry to three equivalent Zr4+ and seven equivalent S2- atoms.
ZrOS is Matlockite structured and crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Zr4+ is bonded in a 9-coordinate geometry to five equivalent S2- and four equivalent O2- atoms. There are one shorter (2.75 Å) and four longer (2.80 Å) Zr–S bond lengths. All Zr–O bond lengths are 2.21 Å. S2- is bonded in a 5-coordinate geometry to five equivalent Zr4+ atoms. O2- is bonded to four equivalent Zr4+ atoms to form a mixture of corner and edge-sharing OZr4 tetrahedra.
Stage 1 ceramic shrouds (high pressure turbine gas path seal) were developed for the GE T700 turbine helicopter engine under the Army/NASA Contract NAS3-23174. This contract successfully proved the viability and benefits of a Stage 1 ceramic shroud for production application. Stage 1 ceramic shrouds were proven by extensive component and engine testing. This Stage 1 ceramic shroud, plasma sprayed ceramic (ZrOs-BY2O3) and bond coating (NiCrAlY) onto a cast metal backing, offers significant engine performance improvement. Due to the ceramic coating, the amount of cooling air required is reduced 20% resulting in a 0.5% increase in horsepower and a 0.3% decrease in specific fuel consumption. This is accomplished with a component which is lower in cost than the current production shroud. Stage 1 ceramic shrouds will be introduced into field service in late 1987.