Non-white cubic and tetragonal oxides

Abstract

Provided are zirconium-based oxides that are colored, e.g., not white or off-white, without inclusion of a pigment, such as by controlling the bandgap of the oxide material to, e.g., less than about 4eV. The oxide preferably includes cubic and / or tetragonal Zirconium Dioxides. Also provided are methods for preparing coatings from such oxides, methods of preparing coatings that comprise such oxides, and to coatings that comprise such oxides.

Description

[0001] P73615

[0002] Non-White Cubic and Tetragonal Oxides

[0003] Cross-Reference to Related Applications

[0004] This Application is an International Application claiming the benefit of priority of U.S. Provisional Application No. 63 / 683,540, filed August 15, 2024, the disclosure of which is expressly incorporated by reference herein in its entirety.

[0005] Field of the Invention

[0006] The disclosure relates to zirconium-based oxides, including cubic and / or tetragonal oxides, that are colored, i.e., non-white, without inclusion of a pigment. The invention also relates to methods for preparing coatings from such oxides, to methods of preparing coatings that comprise such oxides, and to coatings that comprise such oxides.

[0007] Background of the Invention

[0008] Cubic and tetragonal Zr-based oxides, oxides being a class of ceramics, are important materials for engine components exposed to high temperatures. Two such components of gas turbine engines are a thermal barrier coating (TBC) that protects the component, and an abradable layer. The abradable layer is generally applied on top of the thermal barrier coating which itself is generally applied to a substrate or substrate plus bond coat to promote adhesion. The thermal barrier coating is applied to insulate components from high and prolonged heat loads, which allows for higher operating temperatures and therefore increased efficiency with less risk of thermal exposure to the structural components. The abradable coating is applied in aircraft engines to increase efficiency by maintaining a minimal gap between the blade tips and the shroud.

[0009] Since the abradable and thermal barrier coating are both typically a white or off-white oxide material, it can be difficult to visually determine if the layers have been appropriately applied and to what degree the coatings have been worn away during operation. It is thus a challenge to determine if these components of the engine require service.

[0010] The abradable and thermal barrier coatings are typically white or off-white because of a wide bandgap, Eg, that is, a wide band having a zero or near zero density of states of electrons between the material’s occupied states of the valence band (i.e., highest occupied molecular orbitals) and the unoccupied states of the conduction band (i.e. lowest unoccupied molecular orbitals). Thus, attempts to color such materials have typically focused on chemical means, such as by adding pigments. P73615

[0011] US 9,458,064 describes a process for producing bi-colored ceramic bodies of alumina and zirconia type whereby a metal-containing pigment is infiltrated into a green body as a second phase pigment with known color.

[0012] EP 2746243 Al describes a process for producing bi-colored ceramic bodies of alumina whereby a metal-containing pigment is infiltrated into the green body as a second phase pigment with known color.

[0013] EP 3992169 A l describes a process for producing corundum ceramics with white and colored layers are produced whereby a colored light-absorbing dopant is added to hexagonal corundum (aluminum oxide).

[0014] DE 2012304 describes the impregnation of heavy metal solutions into net-shaped technical ceramics with open porosity ideally ranging from 30-50%, which are produced as powder feedstock.

[0015] EP 0704411 Al describes a process for coloring ceramic products based on aqueous solutions.

[0016] WO 1997038952 Al describes a process for coloring ceramic products containing TiO2 and potentially other soluble cations using aqueous or hydroalcoholic solutions applied to the surface before a final heat treatment.

[0017] WO 2002010092 Al describes a process for coloring pink / orange shades at variable depth of a ceramic mass containing Zn using aqueous or hydroalcoholic solutions containing Cr or Cr and Fe or Cr and Zn or Cr, Fe and Zn inorganic salts or organic derivatives.

[0018] DE 102008026980 Al describes a process for coloring porous ceramic shaped bodies by means of at least one suspension or solution containing metal ions and / or metal complexes.

[0019] US 9,757,310 describes a process for imparting fluorescent coloring to dental ceramics via a solution. The coloring agent described contains one or more of Tb, Er, Pr, or Mn and the fluorescing agent contains Bi.

[0020] EP 2239246 Bl describes a process for coloring ceramics using ionic solutions containing rare earth metals and sub-group elements.

[0021] EP 2112252 Al describes a thermal barrier coating containing titanium dioxide or a blend of titanium dioxide with at least one other ceramic material. Oxygen loss from titanium dioxide during plasma spraying is disclosed to create a deep gray to black coating.

[0022] There remains a need for thermal barrier coatings and abradable coatings that are readily visually differently colored. There remains a need for thermal barrier coatings and / or abradable coatings that are colored without using pigments, e.g., that are colored using physical methods rather than chemical methods. P73615

[0023] Summary of the Invention

[0024] It has been surprisingly discovered that it is possible to control the color of oxides, such as zirconium-based oxides, by adjusting the wavelengths of light energy absorbed, reflected, and / or transmitted by the material. One such method is by adjusting the bandgap (i.e., the wavelengths of light absorbed by the material) thereof, such as by including dopant cations that alter the electron orbital energy levels and the number of electrons available to excite from the valence to the conduction band. A similar mechanism, charge transfer, involves the selective absorption of light energy to allow an electron to move from one ion to another.

[0025] The present disclosure provides a composition comprising a majority atom% zirconium dioxide based on total cation content, comprising zirconium dioxide in cubic and / or tetragonal phase, and having a bandgap of less than or equal to 4eV.

[0026] The composition preferably has values of L<90 on the CIE LCH scale. The composition preferably has at least 50% phase fraction of the zirconium dioxide in the cubic and / or the tetragonal phase. Preferably, the composition has a bandgap of less than or equal to 3.6 eV.

[0027] Some preferred compositions include oxides of (in atom%):

[0028] X2: Cr: 0.01-20.0, Y: 5-25;

[0029] X3: Mn: 0.01-20.0, Y: 5-25;

[0030] X4: Ti: 0.01-20.0, Y: 5-25;

[0031] X5: Mg: 0.01-20.0, Y: 5-25;

[0032] X6: Mn: 0.01-20.0, Y: 5-25;

[0033] X7: Ni: 0.01-20.0, Y: 5-25;

[0034] X8: V: 0.01-20.0, Y: 5-25;

[0035] X9: Al: 0.01-20.0, Mn: 0.01-20.0, Y: 5-25;

[0036] XI 1: Mg: 0.01-20.0, Mn: 0.01-20.0, Y: 5-25;

[0037] X12: Ni: 0.01-20.0, Ti: 0.01-20.0, Y: 5-25;

[0038] X15: Fe: 0.01-20.0, Y: 5-25;

[0039] X16: Fe: 0.01-20.0, Gd: 0.01-20.0, Ti: 0.01-20.0, Y: 5-25;

[0040] X17: Ce: 0.01-20.0, Gd: 0.01-20.0, Y: 5-25;

[0041] X21: Nd: 0.01-20.0, Y: 5-25;

[0042] X24: Er: 0.01-20.0, Y: 5-25;

[0043] X25: Dy: 0.01-20.0, Y: 5-25; P73615

[0044] X26: Yb: 0.01-20.0, Y: 5-25;

[0045] X29: Nd: 0.01-20.0, V: 0.01-20.0, Y: 5-25;

[0046] X30: Cr: 0.01-20.0, V: 0.01-20.0, Y: 5-25;

[0047] X32: Ce: 0.01-20.0, Gd: 0.01-20.0, La: 0.01-20.0, Yb: 0.01-20.0, Y: 5-25;

[0048] X33: Fe: 0.01-20.0, Mg: 0.01-20.0, Y: 5-25;

[0049] X44: Er: 0.01-20.0, Nd: 0.01-20.0, Y: 5-25;

[0050] X45: Al: 0.01-20.0, Mg: 0.01-20.0, Y: 5-25;

[0051] X46: Ce: 0.01-5, Dy: 0.01-5, Gd: 0.01-5, La: 0.01-5, Mg: 0.01-5, Nd: 0.01-5, Ni:.01-5, Sm: 0.01-5, Y: 5-25;

[0052] X48: Dy: 0.01-20, Nd: 0.01-20, Ti: 0.01-20, Yb: 0.01-20, Y: 5-25;

[0053] X50: Ce: 0.01-5, Er: 0.01-10, Dy: 0.01-5, La: 0.01-5, Mg: 0.01-5, Yb: 0.01-5, Y: 5-25;

[0054] X51: Al: 0.01-25, Co: 0.01-25, Y: 5-25;

[0055] X52: Ho: 0.01-15, Y: 1-25;

[0056] X53: In: 0.01-15, Y: 1-25;

[0057] X54: Pr: 0.01-15, Y: 1-25;

[0058] X55: Tb: 0.01-15, Y: 1-25;

[0059] X56: Tm: 0.01-15, Y: 1-25;

[0060] X57: Eu: 0.01-15, Y: 1-25;

[0061] X58: Lu: 0.01-15, Y: 1-25;

[0062] X59: Th: 0.01-15, Y: 1-25;

[0063] Y15: Cr: 0.01-5, Er: 0.01-5, Eu: 0.01-5, Fe: 0.01-5, Ho: 0.01-5, La: 0.01-5, Mg: 0.01-, Mn: 0.01-5, Nd: 0.01-5, Ni: 0.01-5, Pr: 0.01-5, Si: 0.01-5, Sm: 0.01-5, Sn: 0.01-5, Tb:.01-5, Tm: 0.01-5, Ti: 0.01-5, Yb: 0.01-5;

[0064] Y18: Cr: 0.01-5, Er: 0.01-5, Eu: 0.01-5, Fe: 0.01-5, Ho: 0.01-5, La: 0.01-5, Mg: 0.01-0, Mn: 0.01-10, Nd: 0.01-5, Ni: 0.01-5, Sm: 0.01-5, Ti: 0.01-5, Yb: 0.01-5;

[0065] Y22: Ca: 0.01-20, Y:l-25;

[0066] Y23: Ce: 0.01-20, Y:l-25;

[0067] Y46: Er: 0.01-5, Fe: 0.01-5, La: 0.01-5, Sm: 0.01-5, Sn: 0.01-5, Ti: 0.01-5, Yb: 0.01-5;

[0068] Y47: Cr: 0.01-5, Er: 0.01-5, Fe: 0.01-5, La: 0.01-5, Mg: 0.01-10, Mn: 0.01-10, Nd:.01-5, Ni: 0.01-10, Sm: 0.01-5, Ti: 0.01-5, Yb: 0.01-5;

[0069] Y48: Er: 0.01-5, Fe: 0.01-10, Mg: 0.01-10, Mn: 0.01-10, Nd: 0.01-5, Ni: 0.01-5, Sm:.01-5, Ti: 0.01-5, Yb: 0.01-5;

[0070] Y56: Fe: 0.01-10, Hf: 0.01-10, Mg: 0.01-10, Ti: 0.01-10;

[0071] Y59: Dy: 0.01-15, Er: 0.01-10, Fe: 0.01-15, Lu: 0.01-10, Mg: 0.01-10, Ti: 0.01-15; P73615

[0072] Y60: Dy: 0.01-15, Er: 0.01-10, Fe: 0.01-15, Lu: 0.01-15, Mg: 0.01-10, Ti: 0.01-10;

[0073] Y62: Ce: 0.01-10, Dy: 0.01-10, Ti: 1-20;

[0074] Y65: Er: 0.01-15, Fe: 0.01-15, Hf: 0.01-10, Lu: 0.01-15, Mg: 0.01-10, Ti: 0.01-15;

[0075] Y68: In: .01-5, Mn: .01-3, Y: .01-25;

[0076] Y69: In: .01-15, Mn: .01-15, Y: .01-25;

[0077] Y70: In: .01-10, Mn: .01-5, Y: .01-25;

[0078] Y74: Fe: 1-10, La: 1-5, Y: 1-25;

[0079] Y75: Ce: 0.01-5, Dy: 0.01-5, Fe: 0.01-10, Hf: 0.01-5, La: 0.01-5, Mg: 0.01-10, Y: 0.01-5, Yb: 0.01-5;

[0080] Y76: Ce: 1-15, Dy: 0.01-5, La: 0.01-5, Mg: 0.01-5, Ti: 0.01-25, Y: 0.01-5, Yb: 0.01-5; Y77: Ce: 1-10, Dy: 0.01-5, Fe: 0.01-15, La: 0.01-5, Mg: 0.01-5, Y: 0.01-5, Yb: 0.01-5; Y78: Al: 1-5, Ce: 1-10, Dy: 0.01-5, Fe: 0.01-15, La: 0.01-5, Mg: 0.01-5, Ti: 0.01-15, Y: 0.01-5, Yb: 0.01-5;

[0081] Y79: Ce: 1-10, Dy: 0.01-5, Fe: 0.01-10, Hf: 0.01-5, La: 0.01-5, Mg: 0.01-10, Ti: 0.01- 15, Y: 0.01-5, Yb: 0.01-5;

[0082] Y82: Ce: 1-10, Gd: 0.01-5, La: 0.01-5, Mg: 0.01-10, Ti: 0.01-10, Yb: 0.01-5;

[0083] Y83: Ce: 1-10, Gd: 0.01-5, La: 0.01-5, Mg: 0.01-10, Ti: 0.01-10, Y: 0.01-5, Yb: 0.01- 5; and

[0084] Y84: Ce: 1-10, Fe: 0.01-10, Gd: 0.01-5, Hf: 0.01-5, La: 0.01-5, Mg: 0.01-10, Ti: 0.01- 20, Yb: 0.01-5; each composition further comprising up to 10 atom% Hf, and up to 10 at% total impurities, the balance being Zirconium.

[0085] Also provided is a sintered pellet of compositions disclosed herein having a sand (also known as “CMAS”) corrosion resistance with penetration depth less than double the penetration depth of a sintered pellet of 8YSZ or Gd2Zr3O7 for at least one composition of sand (e.g., CMAS containing 29.5% CaO, 7.8% MgO, 11.3% A12O3, 50.4% SiO2, 0.1% Fe3O3, 0.4% ZrO2, and 0.5% other trace oxides; or CMFAS containing 16.2% CaO, 3.9% MgO, 19.2% AhO3, 42.5% SiO3, 15.4% FeO, 1.1% ZrO2, and 1.7% other trace oxides; all in weight %) for at least one temperature (e.g., 135O°C), time (e.g., 8 hours), and loading fraction (e.g., 30 mg / cm2). Also provided is the sintered pellet having a sand corrosion penetration depth that is at least 50% better than a sintered pellet of 8YSZ or GdiZ O? for at least one composition of sand for at least one temperature, time, and loading fraction.

[0086] Also provided is a coated surface comprising at least a first coating thereon, wherein the first coating comprises a majority atom% zirconium dioxide based on total metal content, P73615 and has a bandgap of less than or equal to 4eV. The first coating can comprise, consist essentially of, or consist of, the compositions as described above. Also provided is the coated surface having a furnace cycle lifetime of greater than 100 cycles. Also provided is the coated surface having a furnace cycle lifetime at least 50% of the cycles of a surface coated with 8YSZ.

[0087] Also provided is a coating, e.g., a thermal barrier coating, having a thermal diffusivity less than or equal to the thermal diffusivity of a coating of 8YSZ prepared with similar porosity or by similar deposition method (e.g., plasma spraying, electron beam physical vapor deposition, or sol-gel).

[0088] Also provided is a coating, e.g., a thermal barrier coating, having a coefficient of thermal expansion (CTE) similar to the CTE of a coating of 8YSZ (between 8-15x106 / °C when measured from 20°C to 1350°C) prepared with similar porosity or by similar deposition method (e.g., plasma spraying, electron beam physical vapor deposition, or sol-gel).

[0089] Also provided is a coating, e.g., a thermal barrier coating, having an elastic modulus that is low enough for strain tolerance and sufficiently high for mechanical integrity and resistance to damage. The modulus is preferably dependent on the coating material being replaced in the system and is preferably within ±40% of the modulus of the replaced material. For example, 8YSZ’s in-service elastic modulus is often reported as 100 GPa with values between 60 GPa and 140 GPa being acceptable.

[0090] Also provided is a coated surface comprising at least a first coating thereon, and at least a second coating over the first coating; wherein at least one of the first and second coatings comprises a majority atom% zirconium dioxide based on total metal content, and has a bandgap of less than or equal to 4eV ; and wherein a difference in color between the first and second coatings is AE>1 or AH>2.5 degrees based on the CIE LCH scale. The first and / or second coatings can comprise, consist essentially of, or consist of, the compositions as described above.

[0091] Also included is the coated surface wherein each of the first coating and the second coating (a) comprises a majority atom% zirconium dioxide based on total metal content of the respective coating, and (b) has a bandgap of less than or equal to 4eV. Also included is the coated surface of claim 200, wherein the color difference AE is AE>2.5.

[0092] Brief Descriptions of the Drawings

[0093] Figure 1 is a representative graph of density of states (DOS) versus energy (eV). The bandgap is defined as the distance, in electron volts (eV), from the valence to the conduction P73615 band in the density of states. The representative figure depicts the total DOS (TDOS) for tetragonal 8YSZ calculated using the Perdew-Burke-Ernzerhof (PBE) functional.

[0094] Figure 2 is a representative Tauc plot, which can be used to obtain an approximate value of the bandgap. The Tauc plot shown is from a measurement of a tetragonal oxide with nominal chemistry 1.7 at% Y, 2.5 at% Ce, 1.75 at% Dy, 5 at% Hf, 1.8 at% La, 1.6 at% Mg, 1.7 at% Yb, and Zr as the balance element.

[0095] Figure 3 is a schematic representation of one or more coatings of different color that can be applied to a substrate.

[0096] Figure 4 schematically illustrates processing a powder of one or more types of particle to obtain a product having a different color than the powder.

[0097] Figure 5 is a representative XRD pattern for cubic materials, such as coatings described herein. Diamond shaped markers are used to denote peaks for the cubic phase.

[0098] Figure 6 is a representative XRD pattern for tetragonal materials, such as coatings described herein. Diamond shaped markers are used to denote peaks for the tetragonal phase while circular markers identify a minor amount of remnant monoclinic phase.

[0099] Detailed Description

[0100] This disclosure generally relates to tetragonal and cubic Zr-based oxides. Zirconium Dioxide, ZrCL, has an experimental bandgap of approximately 5-7 eV depending on the crystal structure (cubic, monoclinic, tetragonal, or amorphous). Therefore, without modifications such as the addition of chromophores (e.g., pigments, dyes) or introduction of crystal defects, it has a white or off-white color.

[0101] This disclosure aims to improve the application and servicing of Zr-based oxide components by creating visual indicators, i.e., ceramics with distinctly non- white coloring through bandgap tailoring. The technology is expected to be of significant importance to the luxury goods, consumer goods, and manufacturing industry at large. The concentration of the dopants used to achieve tailoring of the bandgap must be controlled to obtain the desired color while also avoiding a decrease in performance (e.g., reduced service lifetimes or brittle behavior).

[0102] It has been found that including proper amounts of other metal oxides or metals, the bandgap can be adjusted and narrowed to the extent that visible light has sufficient energy to excite electrons from the valence band to the conduction band. As an example, if the bandgap is tailored to enable absorption of violet light, this depletes the reflected / diffused light of the absorbed violet wavelengths, causing the oxide to appear yellow (the P73615 complementary color to violet). The selective absorption and / or transmission of certain wavelength(s) of light that ultimately produces a colored oxide is herein generally referred to as the “bandgap.” Several mechanisms by which this occurs include band theory, dispersed metal ions (also known as transition metal impurities), charge transfer phenomena, and color centers. Each could play a role in the observed colors of the disclosed oxides; however, it is challenging to determine the precise contribution of each mechanism to the observed color. Physical optics (i.e., not involving the absorption of light), such as lamellar structure, thin film interference, and diffraction effects are not relevant to the inventive oxides disclosed, and are preferably not included.

[0103] A zirconia-based material having a bandgap of greater than about 3.6eV will appear white or off-white (in the absence of, e.g., dyes or pigments). Any adjustment to the chemical composition of cubic or tetragonal ZrO that confers a visibly non-white color to the material is within the scope of this disclosure. It is preferable that the observed color is achieved by adjusting or obtaining any bandgap that confers a visibly non-white color to the material. Thus, a zirconia-based material according to the present disclosure preferably has a bandgap of 4eV or less, 3.6eV or less, 3.2eV or less, 2.8eV or less, 2.4eV or less, 2eV or less, 1.6eV or less, or 1.2eV or less. There is no lower bound for the bandgap: values as low as OeV are contemplated, as are greater (i.e., non-zero) values such as 0.4eV or greater, 0.8eV or greater, or 1.2eV or greater.

[0104] With visible wavelengths defined as ranging from red (1.6eV; 780nm) to violet (3.6eV; 340nm), the oxides described herein have a bandgap less than 4eV such that the material is observed to be, e.g., black, grey, or red through violet.

[0105] In one aspect, the ceramic (or zirconia-based oxide material) can be described by a compositional range (all provided in atomic %) comprising Oxygen as the majority anion (> 50% atomic % of the occupied anion sites) species with Zirconium as the majority cation (> 50 atomic %) plus one or more other elements as dopants to alter the bandgap and preferably the perceived color.

[0106] In some aspects, the Zirconium Dioxide is further stabilized in the cubic or tetragonal phase with one or more of the following dopants: Yttrium, Cerium, Calcium, Lanthanum, Magnesium, and / or Ytterbium.

[0107] In some aspects, the cation dopant(s) of interest can be included in the composition by adding metallic element(s) (e.g., one or more of Co, Cr, or V) and / or by adding more complex compounds such as oxides or carbides (e.g., one or more of CnCh, CriCb. or COAI2O4) possibly containing additional elements. P73615

[0108] In some aspects the cation composition comprises about 50-99 at% Zr and 0.001-50 at% of one or a combination of antimony, barium, bismuth, chromium, cobalt, copper, dysprosium, erbium, europium, indium, iron, gadolinium, holmium, indium, lanthanum, lithium, magnesium, manganese, molybdenum, neodymium, nickel, niobium, praseodymium, samarium, scandium, silicon, strontium, tellurium, terbium, thulium, tin, titanium, tungsten, vanadium, ytterbium, yttrium, zinc. In another more preferred aspect, the dopant(s) atom composition comprises about 0.01-30 at% of the cation concentration. In a still more preferred aspect, the dopant(s) atom composition comprises about 0.1-10 at% of the cation concentration. All atom percents are based on total atom amounts of the cation species.

[0109] In a more specific aspect, the cations in the ceramic material comprise one of the following atom percents, with Zr being the balance cation in all oxide examples:

[0110] X2: Cr: 0.01-20.0, Y: 5-25 more preferably Cr: 0.01-10, Y: 5-20

[0111] X3: Mn: 0.01-20.0, Y: 5-25 more preferably Mn: 0.01-10, Y: 5-20

[0112] X4: Ti: 0.01-20.0, Y: 5-25 more preferably Ti: 0.01-10, Y: 5-20

[0113] X5: Mg: 0.01-20.0, Y: 5-25 more preferably Mg: 0.01-10, Y: 5-20

[0114] X6: Mn: 0.01-20.0, Y: 5-25 more preferably Mn: 0.01-10, Y: 5-20

[0115] X7: Ni: 0.01-20.0, Y: 5-25 more preferably Ni: 0.01-10, Y: 5-20

[0116] X8: V: 0.01-20.0, Y: 5-25 more preferably V: 0.01-10, Y: 5-20

[0117] X9: Al: 0.01-20.0, Mn: 0.01-20.0, Y: 5-25 more preferably Al: 0.01-10, Mn: 0.01-10, Y: 5-20

[0118] XI 1: Mg: 0.01-20.0, Mn: 0.01-20.0, Y: 5-25 more preferably Mg: 0.01-10, Mn: 0.01-10, Y: 5-20

[0119] X12: Ni: 0.01-20.0, Ti: 0.01-20.0, Y: 5-25 more preferably Ni: 0.01-10, Ti: 0.01-10, Y: 5-20

[0120] X15: Fe: 0.01-20.0, Y: 5-25 more preferably Fe: 0.01-10, Y: 5-20

[0121] X16: Fe: 0.01-20.0, Gd: 0.01-20.0, Ti: 0.01-20.0, Y: 5-25 P73615 more preferably Fe: 0.01-10, Gd: 0.01-10, Ti: 0.01-10, Y: 5-20

[0122] X17: Ce: 0.01-20.0, Gd: 0.01-20.0, Y: 5-25 more preferably Ce: 0.01-10, Gd: 0.01-10, Y: 5-20

[0123] X21: Nd: 0.01-20.0, Y: 5-25 more preferably Nd: 0.01-10, Y: 5-20

[0124] X24: Er: 0.01-20.0, Y: 5-25 more preferably Er: 0.01-10, Y: 5-20

[0125] X25: Dy: 0.01-20.0, Y: 5-25 more preferably Dy: 0.01-10, Y: 5-20

[0126] X26: Yb: 0.01-20.0, Y: 5-25 more preferably Yb: 0.01-10, Y: 5-20

[0127] X29: Nd: 0.01-20.0, V: 0.01-20.0, Y: 5-25 more preferably Nd: 0.01-10, V: 0.01-10, Y: 5-20

[0128] X30: Cr: 0.01-20.0, V: 0.01-20.0, Y: 5-25 more preferably Cr: 0.01-10, V: 0.01-10, Y: 5-20

[0129] X32: Ce: 0.01-20.0, Gd: 0.01-20.0, La: 0.01-20.0, Yb: 0.01-20.0, Y: 5-25 more preferably Ce: 0.01-10, Gd: 0.01-10, La: 0.01-10, Yb: 0.01-10, Y: 5-20

[0130] X33: Fe: 0.01-20.0, Mg: 0.01-20.0, Y: 5-25 more preferably Fe: 0.01-10, Mg: 0.01-10, Y: 5-20

[0131] X44: Er: 0.01-20.0, Nd: 0.01-20.0, Y: 5-25 more preferably Er: 0.01-10, Nd: 0.01-10, Y: 5-20

[0132] X45: Al: 0.01-20.0, Mg: 0.01-20.0, Y: 5-25 more preferably Al: 0.01-10, Mg: 0.01-10, Y: 5-20

[0133] X46: Ce: 0.01-5, Dy: 0.01-5, Gd: 0.01-5, La: 0.01-5, Mg: 0.01-5, Nd: 0.01-5, Ni: Sm: 0.01-5, Y: 5-25

[0134] X47: Al: 0.01-10, La: 0.01-5, Si: 0.01-10, Y: 5-25

[0135] X48: Dy: 0.01-20, Nd: 0.01-20, Ti: 0.01-20, Yb: 0.01-20, Y: 5-25 more preferably Dy: 0.01-5, Nd: 0.01-5, Ti: 0.01-5, Yb: 0.01-5, Y: 5-20

[0136] X49: Ce: 0.01-20, Dy: 0.01-20, La: 0.01-20, Yb: 0.01-20, Y: 5-25 more preferably Ce: 0.01-5, Dy: 0.01-5, La: 0.01-5, Yb: 0.01-5, Y: 5-20

[0137] X50: Ce: 0.01-5, Er: 0.01-10, Dy: 0.01-5, La: 0.01-5, Mg: 0.01-5, Yb: 0.01-5, Y: 5-25

[0138] X51: Al: 0.01-25, Co: 0.01-25, Y: 5-25 more preferably Al: 0.01-15, Co: 0.01-10, Y: 5-25

[0139] X51-1: Co: 0.01-25, Y: 5-25 P73615

[0140] X52: Ho: 0.01-15, Y: 1-25

[0141] X53: In: 0.01-15, Y: 1-25

[0142] X54: Pr: 0.01-15, Y: 1-25

[0143] X55: Tb: 0.01-15, Y: 1-25

[0144] X56: Tm: 0.01-15, Y: 1-25

[0145] X57: Eu: 0.01-15, Y: 1-25

[0146] X58: Lu: 0.01-15, Y: 1-25

[0147] X59: Th: 0.01-15, Y: 1-25

[0148] Y15: Cr: 0.01-5, Er: 0.01-5, Eu: 0.01-5, Fe: 0.01-5, Ho: 0.01-5, La: 0.01-5, Mg: 0.01-, Mn: 0.01-5, Nd: 0.01-5, Ni: 0.01-5, Pr: 0.01-5, Si: 0.01-5, Sm: 0.01-5, Sn: 0.01-5, Tb:.01-5, Tm: 0.01-5, Ti: 0.01-5, Yb: 0.01-5

[0149] Y18: Cr: 0.01-5, Er: 0.01-5, Eu: 0.01-5, Fe: 0.01-5, Ho: 0.01-5, La: 0.01-5, Mg: 0.01-0, Mn: 0.01-10, Nd: 0.01-5, Ni: 0.01-5, Sm: 0.01-5, Ti: 0.01-5, Yb: 0.01-5

[0150] Y22: Ca: 0.01-20, Y:l-25 more preferably Ca: 1-10, Y: 1-12

[0151] Y23: Ce: 0.01-20, Y: l-25

[0152] Y46: Er: 0.01-5, Fe: 0.01-5, La: 0.01-5, Sm: 0.01-5, Sn: 0.01-5, Ti: 0.01-5, Yb: 0.01-5

[0153] Y47: Cr: 0.01-5, Er: 0.01-5, Fe: 0.01-5, La: 0.01-5, Mg: 0.01-10, Mn: 0.01-10, Nd:.01-5, Ni: 0.01-10, Sm: 0.01-5, Ti: 0.01-5, Yb: 0.01-5

[0154] Y48: Er: 0.01-5, Fe: 0.01-10, Mg: 0.01-10, Mn: 0.01-10, Nd: 0.01-5, Ni: 0.01-5, Sm:.01-5, Ti: 0.01-5, Yb: 0.01-5

[0155] Y56: Fe: 0.01-10, Hf: 0.01-10, Mg: 0.01-10, Ti: 0.01-10

[0156] Y59: Dy: 0.01-15, Er: 0.01-10, Fe: 0.01-15, Lu: 0.01-10, Mg: 0.01-10, Ti: 0.01-15

[0157] Y60: Dy: 0.01-15, Er: 0.01-10, Fe: 0.01-15, Lu: 0.01-15, Mg: 0.01-10, Ti: 0.01-10

[0158] Y62: Ce: 0.01-10, Dy: 0.01-10, Ti: 1-20

[0159] Y65: Er: 0.01-15, Fe: 0.01-15, Hf: 0.01-10, Lu: 0.01-15, Mg: 0.01-10, Ti: 0.01-15

[0160] Y68: In: .01-5, Mn: .01-3, Y: .01-25

[0161] Y69: In: .01-15, Mn: .01-15, Y: .01-25 more preferably In: 2-10, Mn: 2-10, Y: 1-10

[0162] Y70: In: .01-10, Mn: .01-5, Y: .01-25

[0163] Y74: Fe: 1-10, La: 1-5, Y: 1-25

[0164] Y75: Ce: 0.01-5, Dy: 0.01-5, Fe: 0.01-10, Hf: 0.01-5, La: 0.01-5, Mg: 0.01-10, Y:.01-5, Yb: 0.01-5

[0165] Y76: Ce: 1-15, Dy: 0.01-5, La: 0.01-5, Mg: 0.01-5, Ti: 0.01-25, Y: 0.01-5, Yb: 0.01-5 P73615

[0166] Y77: Ce: 1-10, Dy: 0.01-5, Fe: 0.01-15, La: 0.01-5, Mg: 0.01-5, Y: 0.01-5, Yb: 0.01-5 Y78: Al: 1-5, Ce: 1-10, Dy: 0.01-5, Fe: 0.01-15, La: 0.01-5, Mg: 0.01-5, Ti: 0.01-15, Y: 0.01-5, Yb: 0.01-5

[0167] Y79: Ce: 1-10, Dy: 0.01-5, Fe: 0.01-10, Hf: 0.01-5, La: 0.01-5, Mg: 0.01-10, Ti: 0.01- 15, Y: 0.01-5, Yb: 0.01-5

[0168] Y82: Ce: 1-10, Gd: 0.01-5, La: 0.01-5, Mg: 0.01-10, Ti: 0.01-10, Yb: 0.01-5

[0169] Y83: Ce: 1-10, Gd: 0.01-5, La: 0.01-5, Mg: 0.01-10, Ti: 0.01-10, Y: 0.01-5, Yb: 0.01- 5

[0170] Y84: Ce: 1-10, Fe: 0.01-10, Gd: 0.01-5, Hf: 0.01-5, La: 0.01-5, Mg: 0.01-10, Ti: 0.01- 20, Yb: 0.01-5.

[0171] Each of the compositions disclosed herein can contain up to 10 atomic %, preferably up to 6 atomic % or 3 atomic %, of other components, such as total impurities (e.g., some common impurities in ZrO2 are Fe, Ca, Cu, Ti, Mg, or Si), excluding Hf which is difficult to separate from Zr. Thus, each of the compositions disclosed herein can additionally contain up to 10 atomic % of Hf, preferably up to 6 atomic %, or 3 atomic %. In this regard, “other components” could include any element or compound not listed for a particular composition provided that it does not turn a composition white or off-white, as defined herein.

[0172] In some aspects, a colored oxide can be applied to another alloy or ceramic of a different coloring in one or more layers, as schematically shown in Figure 3.

[0173] In some aspects, the powder with overall composition of the oxide has a different color than the sintered or fired or heat treated or thermal sprayed or otherwise processed oxide. This can be accomplished, for example, with a powder that is a mixture of particles of different composition (e.g., different oxides) as shown in Figure 4, or where the powder is formed by agglomerating (e.g., spray drying) a mixture of oxides.

[0174] Electronic Structure Criteria:

[0175] In some aspects, the oxide can be described by the electron orbital features it possesses. The colored oxides described herein exhibit a bandgap such that certain wavelengths of visible light are absorbed, and others are observed. With visible wavelengths defined as ranging from red (1.6eV; 780nm) to violet (3.6eV; 340nm), the oxides described herein have a bandgap less than 4eV (310 nm) such that the material is observed to be black, grey, or red through violet. As seen in Figure 1, the bandgap is defined as the distance, in electron volts (eV) from the valence to the conduction band in the density of states (DOS). The electronic structure in the oxide material responsible for the observed color can result P73615 from one or a combination of several of non-physical (i.e., requiring the absorption of light) mechanisms: band theory, dispersed metal ions, charge transfer phenomena, and color centers. Physical phenomena are rarely related directly to the chemistry of the material, but instead result from the texture or internal arrangement (E. Fritsch et al., “An Update on Color in Gems. Part 3: Colors Caused by Band Gaps and Physical Phenomena,” Gems & Gemology, p. 81-102, summer 1988) and are outside the scope of the oxides disclosed herein.

[0176] In some aspects, the optical bandgap can be approximated by Tauc plot analysis, an extrapolation method. The Tauc method relies on absorbance data and / or reflectance data. As is known in the art, by fitting a line to a chosen point on the linear portion of the Tauc plot, such as the inflection point of the curve, and extending the line to the x-axis, it is possible to estimate the optical gap energy corresponding to several different types of electronic transitions (e.g., direct allowed, direct forbidden, indirect allowed, or indirect forbidden). See Figure 2.

[0177] Phase Fraction / Microstructure Criteria:

[0178] In some aspects, the oxide can be described by the microstructural features it possesses. In general, high fractions of tetragonal or cubic zirconia phase are desirable. Figure 5 and Figure 6 show representative XRD patterns for the cubic and tetragonal materials fabricated. The peaks belonging to phases of interest are marked with diamonds, and peaks belonging to other phases are marked with circles. In some aspects, the cubic or tetragonal phase of interest constitutes at least 50% phase fraction; in a more preferred aspect it constitutes at least 80% phase fraction; and in a still more preferred embodiment greater than 95% phase fraction.

[0179] The crystal structure(s) and phase fraction(s) can be determined by an ordinary practitioner by methods such as X-ray diffraction (XRD) and / or transmission electron microscopy.

[0180] Optical Criteria:

[0181] The inventive ceramics include cubic and tetragonal zirconia-based oxides with dopants added to modify the bandgap and achieve coloring of the product. To take full advantage of the benefits of these oxides being colored, it is important that the product be visually distinct from the typical oxides, such as YSZ or alumina, that are often described as white, off-white, or cream in color. Simple colorimeters, spectrophotometers, or other color measurement devices or color standards (e.g., the Munsell Book of Colour or Inter-Society Color Council-National Bureau of Standards Centroid Color Charts) can be used to evaluate the color of a material. P73615

[0182] While different color spaces exist, the values reported herein utilize the Lightness (L), Chroma (C), and Hue (H), LCH color space defined by the International Commission on Illumination (CIE) since it contains all colors perceivable to the human eye and separates the Lightness, Chroma, and Hue (LCH) components.

[0183] Hue can be described as the color of the rainbow (red through violet) and Chroma the saturation. All materials, even white YSZ, will have a Hue component; although the high Lightness and low Chroma values are the LCH components that primarily describe their white nature. The Lightness component being high, greater than about 90, alone can be sufficient to define a material as white in the CIE LCH color space. In some aspects, the LCH values of the white oxides are such that Lightness is greater than 70 and Chroma less than 5. In some still preferred aspects, oxides that would be described as white have Lightness greater than 75 and Chroma less than 5. Put another way, non-white materials have L<90, preferably L<80 and C>5. For example, a non-white material has either L<90 or C>5.

[0184] As used in this disclosure, a difference in color can be defined as the difference in H values, AH=IH2-Hil, between two materials when at least one of the materials is not white as described above. A difference in color can also be defined using the CIE color difference 1 formula AE = (AL2+ AC2+ AH2) Of these, AE is the preferred metric.

[0185] Any color difference, e.g., relative to substrate, great enough to be objectively different is sufficient for a coating, or coatings, as disclosed herein. Preferably, the color difference AH is at least or greater than 2.5 degrees, 5 degrees, 10 degrees, 20 degrees, 30 degrees, 45 degrees, 90 degrees, or 135 degrees. This presumes a shortest path angle with a maximum difference of 180 degrees. Preferably, the color difference AE is at least or greater than 1, 2.5, 6, 15, 25, 50, 100, or 150. This also presumes a shortest path angle for AH, such that the maximum AE would be 229.

[0186] Producing cubic and tetragonal zirconia-based oxides that are non-white has surprisingly proved to be a non-trivial problem. The vast majority of commercially available compositions are visibly white or off-white. Table 1 lists a few such compositions and their respective color measurements. Precise compositions for X47a, X49a, X56a, X57a, X58a, and X59a are provided below Table 1. Table 1

[0187] X47a: Al: 6, La: 2, Si: 6, Y: 8, Zr: Balance

[0188] X48a: Dy: 3, Nd: 3, Ti: 3, Yb: 3, Y: 8, Zr: Balance

[0189] X49a: Ce: 1.5, Dy: 1.5, La: 1.5, Yb: 1.5, Y: 8, Zr: Balance

[0190] X56a: Tm: 6, Y: 8, Zr: Balance

[0191] X57a: Eu: 4, Y: 8, Zr: Balance

[0192] X58a: Lu: 4, Y: 8, Zr: Balance

[0193] X59a: Th: 4, Y: 8, Zr: Balance

[0194] Zirconia Compositions with Decreased Bandgap:

[0195] Pure zirconium dioxide has a bandgap of about 5-7 eV depending on the crystal structure and which elements stabilize the tetragonal and cubic phase. The experimental values are 5.8eV for monoclinic, 6.0eV for yttria-stabilized tetragonal, and 5.3eV cubic. It is within the capability of a person of ordinary skill in the art, using the present specification as a guide, to devise and manufacture zirconium dioxide materials that are colored due to a reduced bandgap, e.g., less than »4 eV, more preferably less than ~3.8 eV, and still more preferably less than ~3.6 eV, or other values as disclosed herein.

[0196] The colored zirconium dioxide disclosed herein can be used as is, or can be used as starting points, with progressive quantitative variations made in atom percentages, or qualitative variations made by adding, deleting, or substituting similar dopants, which can then be quantitatively varied.

[0197] It is also possible to use ab initio, semi-empirical, artificial intelligence, or other computational methods to make theoretical predictions of the bandgap of a composition, which can be evolved using, e.g., Monte Carlo, genetic algorithm, human intuition, random search, or other methods. Example software packages to make theoretical predictions of the bandgap include Vienna Ab initio Simulation Package (VASP) and Quantum Espresso. Example software packages to computationally evolve the composition include PyGAD, GeneHunter, Jenetics, pandas-montecarlo, and Quantlib. The materials can then be prepared, and the bandgaps empirically determined or approximated using, e.g., methods disclosed herein, or other known methods.

[0198] Coatings:

[0199] It is within the capability of a person of ordinary skill in the art, using the present specification as a guide, to apply the colored oxides as a coating.

[0200] In some aspects, the colored oxide coating is applied to a substrate material by a thermal spray process including but not limited to wire flame; plasma; detonation; HVOF; or cold spray. Thermal spray coating processes heat or melt the colored oxide precursor by electrical (e.g., plasma or arc) or chemical (e.g., combustion) and accelerate the particles toward the substrate. The accumulation of the sprayed particles results in a coating.

[0201] In some aspects, the colored oxide coating is applied by sintering, casting, ball milling, sol-gel, hydrothermal, solvothermal, electrodeposition, pulsed laser deposition, or a so-called thin film deposition technique including but not limited to chemical vapor deposition (CVD), physical vapor deposition (PVD), atomic layer deposition (ALD), electron beam deposition (e-beam), or sputtering.

[0202] In some aspects, one or more of the colored oxides are applied as a thermal barrier coating. In some aspects, a bond coat material is deposited between the substrate and the thermal barrier layer to promote adhesion and / or reduce the coefficient of thermal expansion mismatch between the substrate and the TBC.

[0203] In some aspects, one or more of the colored oxides are applied as an abradable coating. In some aspects, the primary role of the abradable coating is to maintain minimal clearance between the blade tips and the casing of an aircraft engine.

[0204] Performance Criteria:

[0205] In some aspects, applicable performance criteria for use as TBCs or abradables include furnace cycle testing (FCT), sand (CMAS) corrosion resistance, coefficient of P73615 thermal expansion (CTE), phase stability after prolonged exposure to high temperature (i.e., thermal stability), thermal conductivity, erosion resistance, burner rig test, abradability, melting point, hardness, elastic modulus, thermal shock resistance, sintering resistance, and coating porosity.

[0206] CMAS corrosion performance is dependent on the chemistry of the CMAS and operating temperature. Furthermore, CMAS performance of a coating of the colored oxides is also impacted by the porosity of the material. For coatings of the colored oxides applied as abradables or TBCs, it is desirable that CMAS corrosion is minimal. Performance to existing standard materials such as GDZ and 8YSZ is preferable. Some standard CMAS chemistries are AFRL-02, CMAS, CMFAS, ISO A4 (Arizona Test Dust), C-spec sand (MIL E-5007), and AFRL-03. Standard temperature ranges for the test include 1000°C to 1500°C. Typical durations of the test range from 5-20 hours. The chemistry of the sand, temperature, and duration of the test can be modified by an ordinary practitioner to best represent the expected operating conditions of the engine.

[0207] In some aspects, the isothermal sand corrosion performance of the colored oxide should be compared to standard TBC materials (such as but not limited to 8YSZ and GDZ) the coating prepared using a similar method and with similar porosity, and the reaction depth is preferably less than 200% of the depth observed in the standard TBC material; in a more preferred aspect it is preferably less than 120% of the depth; and in a still more preferred embodiment less than 90% of the reaction depth observed for the standard material in the same test. In some aspects, the inventive colored oxide material may exhibit better sand corrosion resistance compared to a standard TBC material for some sand chemistries, test duration, and temperatures while exhibiting lesser performance under a different set of conditions.

[0208] When measuring the reaction depth with a dense (> 90%) sample of the colored oxide during a sand corrosion test performed at 1250°C for 8 hours, the reaction depth with some chemistry of sand (e.g., CMAS containing 29.5% CaO, 7.8% MgO, 11.3% AI2O3, 50.4% SiO2, and 0.1% Fe2Oj, 0.4% ZrO2, and 0.5% other trace oxides; all in weight %), is preferably less than 1mm; in a more preferred aspect less than 500pm; and in a still more preferred embodiment less than 250pm as measured from the original surface height of the dense oxide.

[0209] In some embodiments, it is preferable that the colored oxide coating has equivalent (±20%) or better sand corrosion resistance than one of the commonly utilized TBC materials P73615 under at least one set of conditions; still more preferably at least two test conditions; and in a still more preferred embodiment more than three different test conditions.

[0210] TBC coatings of the colored oxides applied as will ideally survive furnace cycle testing without spallation for many cycles. It is important to compare control samples of a YSZ sample suitable for TBC applications (e.g., 8YSZ) to catch infantile failures or poor repeatability that might indicate the results are deposition parameter driven and the deposition parameters should be further optimized. In some aspects, the FCT performance of the colored oxide coating should be compared to standard TBC materials (such as but not limited to 8YSZ or GDZ) and the number of cycles before failure is preferably at least 50% of the number of cycles achieved for the standard TBC material; in a more preferred aspect it is preferably more than 100% of the number of cycles; and in a still more preferred embodiment more than 120% of the number of cycles for a suitable standard material in the same test.

[0211] In absolute terms, the furnace cycle lifetime of an appropriately applied colored oxide coating exposed to a 10 min ramp to 1135°C, 40 min soak at 1135°C, and lOmin cool down is preferably greater than 100 cycles; in a more preferred aspect greater than 150 cycles; and in a still more preferred embodiment greater than 200 cycles.

[0212] TBC coatings of the colored oxides as applied preferably has a coefficient of thermal expansion (CTE) amenable to minimizing thermal expansion spallation in a specific application and system. In some aspects, the CTE of the colored oxide coating should be comparable to standard TBC materials (such as but not limited to 8YSZ or GDZ) with the same nominal porosity and the CTE is preferably within ±50% of the CTE of the standard TBC material; in a more preferred aspect it is preferably within ±30% of the CTE of the standard TBC material; and in a still more preferred embodiment within ±10% of the CTE of the standard TBC material.

[0213] In absolute terms, the mean coefficient of thermal expansion of an appropriately applied colored oxide coating with 10-15% nominal porosity cycled from 20°C to 1350°C is preferably between 5xlO’6 / °C and 15xlO"6 / °C; in a more preferred aspect between 8xlO"6 / °C and 13X10'6 / °C; and in a still more preferred embodiment between 10xl0’6 / °C and 12xlO’6 / °C.

[0214] TBC coatings of the colored oxides as applied preferably has a low thermal diffusivity to protect components from the engine operating temperature. In some aspects, the thermal diffusivity of the colored oxide coating should be compared to standard TBC materials (such as but not limited to 8 YSZ or GDZ) with the same nominal porosity and the thermal diffusivity is preferably less than 150% of the thermal diffusivity of the standard TBC material; in a more preferred aspect it is preferably less than 100% of the thermal diffusivity P73615 of the standard TBC material; and in a still more preferred embodiment less than 85% of the thermal diffusivity of the standard TBC material.

[0215] In absolute terms, the room temperature thermal diffusivity of an appropriately applied colored oxide coating with 10-15% nominal porosity is preferably less than 0.7mm2 / s; in a more preferred aspect it is preferably less than 0.5mm2 / s; and in a still more preferred embodiment it is preferably less than 0.4mm2 / s. As used in this specification, the term “room temperature” means about or equal to 20° C.

[0216] TBC coatings of the colored oxides applied as will ideally have an elastic modulus that is low enough to accommodate strain tolerance and sufficiently high for mechanical integrity and resistance to damage. In some aspects, the elastic modulus of the colored oxide coating should be compared to standard TBC materials (such as but not limited to 8YSZ or GDZ) with the same nominal porosity and the elastic modulus is preferably within ±40% of the modulus of the standard material; in a more preferred aspect it is preferably within ±30% of the elastic modulus of the standard TBC material; and in a still more preferred embodiment within ±10% of the elastic modulus of the standard TBC material.

[0217] In absolute terms, the room temperature impulse excitation soundwave based elastic modulus of an appropriately applied colored oxide coating after three cycles from 20°C to 135O°C is preferably between 20 GPa and 300 GPa; in a more preferred aspect between 40 GPa and 260 GPa; and in a still more preferred embodiment between 60 GPa and 230 GPa.

[0218] Examples

[0219] Example 1:

[0220] The following non-white oxides were fabricated to demonstrate the technology. Samples were prepared by weighing and hand mixing the appropriate ratio of oxide feedstocks together to achieve the target cation ratios. Ball milling was employed to improve the mixing and reduce the diffusion lengths during sintering. Cylindrical disks of ~10mm diameter and ~2mm thick were hand pressed in a die and placed on a zirconia boat. The samples were sintered at an appropriate temperature and for an appropriate duration to form the cubic or tetragonal phase. Samples intended to form cubic ZrCh were sintered for 1600°C for 16 hours while samples intended to form tetragonal ZrO were sintered at 1500°C for 12 hours. Temperature and time may be varied by an ordinary practitioner in the field to achieve the desired phase.

[0221] Samples were polished to a 0.05pm finish and evaluated using a UV-Vis-NIR spectrophotometer with a 150mm integrating sphere attachment. The UV-Vis-NIR data was P73615 collected from 1400 to 250nm wavelengths in reflectance mode with a lOnm step size, a 10 degree observer angle, and a D65 illuminant. A certified sample of Spectralon was used as the reference standard. The color measurement results reported in CIE LCH color space (also known as Lightness, Chroma, and Hue) are show as L, C, and H values rounded to the nearest integer in Table 2. Specific compositions for each oxide sample are provided below Table 2 as X#a or Y#a in atomic % cation and Zr as the balance element.

[0222] Table 2 P73615 P73615

[0223] X2a: Cr: 6, Y: 17.5

[0224] X3a: Mn: 6, Y: 17.5

[0225] X4a: Ti: 6, Y: 17.5

[0226] X5a: Mg: 2, Y: 17.5

[0227] X6a: Mn: 2, Y: 17.5

[0228] X7a: Ni: 2, Y: 17.5

[0229] X8a: V: 2, Y: 17.5

[0230] X9a: Al: 1, Mn: 2, Y: 17.5

[0231] XI la: Mg: 2, Mn: 2, Y: 17.5

[0232] X12a: Ni: 2, Ti: 2, Y: 17.5

[0233] X15a: Fe: 6, Y: 17.5

[0234] X16a: Fe: 6, Gd: 6, Ti: 6, Y: 17.5

[0235] X17a: Ce: 6, Gd: 0.01-20.0, Y: 17.5

[0236] X21a: Nd: 6, Y: 17.5

[0237] X24a: Er: 6, Y: 17.5

[0238] X25a: Dy: 6, Y: 17.5

[0239] X26a: Yb: 6, Y: 17.5

[0240] X29a: Nd: 6, V: 2, Y: 17.5

[0241] X30a: Cr: 6, V: 6, Y: 17.5

[0242] X32a: Ce: 2, Gd: 2, La: 2, Yb: 2, Y: 17.5

[0243] X33a: Fe: 2, Mg: 2, Y: 17.5

[0244] X44a: Er: 6, Nd: 6, Y: 8

[0245] X45a: Al: 6, Mg: 2, Y: 8

[0246] X46a: Ce: 1.5, Dy: 1.5, Gd: 1.5, La: 1.5, Mg: 1.5, Nd: 1.5, Ni: 1.5, Sm: 1.5, Y: 8 P73615

[0247] X48a: Dy: 3, Nd: 3, Ti: 3, Yb: 3, Y: 8

[0248] X50a: Ce: 1.5, Er: 3, Dy: 1.5, La: 1.5, Mg: 1.5, Yb: 1.5, Y: 8

[0249] X51a: Al: 12, Co: 6, Y: 8

[0250] X52a: Ho: 6, Y: 8

[0251] X53a: In: 6, Y: 8

[0252] X54a: Pr: 6, Y: 8

[0253] X55a: Tb: 6, Y: 8

[0254] Y15a: Cr: 1, Er: 1, Eu: 1, Fe: 1, Ho: 1, La: 1, Mg: 1, Mn: 1, Nd: 1, Ni: 1, Pr: L Si: 1, Sm: 1, Sn: 1, Tb: 1, Tm: 1, Ti: 1, Yb: 1

[0255] Y18a: Cr: 1, Er: 1, Eu: 1, Fe: 1, Ho: 1, La: 1, Mg: 3, Mn: 3, Nd: 1, Ni: 3, Sm: 1, Ti: 1,

[0256] Yb: 1

[0257] Y22a: Ca: 2, Y: 8

[0258] Y23a: Ce: 2, Y: 8

[0259] Y46a: Er: 1, Fe: 1, La: 1, Sm: 1, Sn: 1, Ti: 1, Yb: 1

[0260] Y47a: Cr: 1, Er: 1, Fe: 1, La: 1, Mg: 3, Mn: 3, Nd: 1, Ni: 3, Sm: 1, Ti: 1, Yb: 1

[0261] Y48a: Er: 1, Fe: 6, Mg: 4, Mn: 4, Nd: 1, Ni: 2, Sm: 1, Ti: 2, Yb: 1

[0262] Y56a: Fe: 4, Hf: 4, Mg: 4, Ti: 4

[0263] Y59a: Dy: 8, Er: 4, Fe: 8, Lu: 4, Mg: 4, Ti: 8

[0264] Y60a: Dy: 8, Er: 4, Fe: 8, Lu: 8, Mg: 4, Ti: 4

[0265] Y62a: Ce: 4, Dy: 4, Ti: 8

[0266] Y65a: Er: 8, Fe: 8, Hf: 4, Lu: 4, Mg: 4, Ti: 8

[0267] Y68a: In: 2, Mn: 1, Y: 8

[0268] Y69a: In: 4, Mn: 4, Y: 8

[0269] Y70a: In: 4, Mn: 1, Y: 8

[0270] Y74a: Fe: 4, La: 2, Y: 8

[0271] Y75a: Ce: 2.5, Dy: 1.8, Fe: 4, Hf: 1, La: 1.8, Mg: 1.6, Y: 1.7, Yb: 1.7

[0272] Y76a: Ce: 7.2, Dy: 1.8, La: 1.8, Mg: 1.6, Ti: 18, Y: 1.7, Yb: 1.7

[0273] Y77a: Ce: 5, Dy: 1.8, Fe: 8, La: 1.8, Mg: 1.6, Y: 1.7, Yb: 1.7

[0274] Y78a: Al: 2, Ce: 4, Dy: 1.8, Fe: 4, La: 1.8, Mg: 1.6, Ti: 8, Y: 1.7, Yb: 1.7

[0275] Y79a: Ce: 4, Dy: 1.8, Fe: 4, Hf: 2, La: 1.8, Mg: 1.6, Ti: 8, Y: 1.7, Yb: 1.7

[0276] Y82a: Ce: 6, Gd: 1.7, La: 1.6, Mg: 2.6, Ti: 5, Yb: 1.7

[0277] Y83a: Ce: 6, Gd: 1.7, La: 1.6, Mg: 2.6, Ti: 5, Y: 1.7, Yb: 1.7

[0278] Y84a: Ce: 6, Fe: 1, Gd: 1.7, Hf: 1, La: 1.4, Mg: 2.9, Ti: 7, Yb: 1.7. P73615

[0279] Example 2:

[0280] Five experimental oxides were thermal sprayed as a thermal barrier coating for furnace cycle testing. Four samples of each oxide were tested for statistical purposes. Samples were exposed to a 10 min ramp to 1135 °C, 40 min soak at 1135 °C, and lOmin cool down; which denotes a cycle. Furnace cycle test results are shown in Table 3. The test was stopped after 316 cycles; candidate oxides for which none of the samples exhibited failure before the end of the test are marked as “No Failures” and a standard deviation of “N / A”. All compositions for the inventive oxides nominally contain 8 atomic % Y, the listed at% of other dopant(s), and Zr as balance.

[0281] Table 3

[0282] Example 3:

[0283] Cylindrical discs of five experimental oxides were fabricated as described in Example 1 for sand corrosion resistance testing. A sample of 8YSZ was also fabricated in this manner as a control. 30mg / cm2of sand of a specific composition was loaded atop the cylindrical oxide disc and then placed into a furnace at 1250°C or 1350°C for 8 hours. Table 4 details the sand corrosion test conditions and the performance of each oxide. The oxide composition column lists the dopant cations in atomic % with Zr as the balance element for the inventive oxides. Table 5 details example compositions of sand, all in weight %, used for corrosion testing. P73615

[0284] Table 4

[0285] Table 5 P73615

[0286] Example 4:

[0287] Five experimental oxides were thermal sprayed as a thermal barrier coating for coefficient of thermal expansion (CTE) measurements from room temperature to 135O°C. When the materials disclosed herein are applied in some applications, such as thermal barrier coatings, it is ideal that the CTE of the materials in the application have similar values to minimize failures from events such as spalling. For example, an oxide replacing 8YSZ will preferably have a CTE between 8xlO"6 / °C and 15xlO'6 / °C when measured from 20°C to 135O°C. A sample of 8YSZ was also fabricated in this manner as a control. The samples underwent 3 cycles of CTE measurements and quadratic equations were fit to Cycle 2 and Cycle 3. Table 6 details the nominal compositions in atomic % (Zr as balance element) and the mean CTE value from Cycle 3 for each oxide.

[0288] Table 6 P73615

[0289] Example 5:

[0290] Two experimental oxides were thermal sprayed as a thermal barrier coating for measuring thermal diffusivity at room temperature. Lower thermal diffusivity is an ideal characteristic of the materials disclosed herein when applied as a thermal barrier coating in order to maximize protection of the engine. Laser flash analysis was utilized to measure the thermal diffusivity of the as-sprayed thermal barrier coatings with nominally targeted -10-15 vol% porosity. A sample of 8YSZ was also fabricated in this manner as a control. Table 7 details the nominal compositions in atomic % (Zr as balance element) and the room temperature thermal diffusivity.

[0291] Table 7

[0292] Example 6:

[0293] Five experimental oxides were thermal sprayed as a thermal barrier coating with nominally targeted -10-15 vol% porosity for measuring elastic modulus at room temperature. A Sonelastic® system based on the Impulse Excitation Technique (ASTM-E1876) for the accurate and non-destructive characterization of elastic moduli of materials was utilized for testing. The elastic modulus of each oxide material was measured in the “as-sprayed” condition and after 3 cycles of CTE measurements from room temperature to 1350°C. A sample of 8YSZ was also fabricated in this manner as a control. The measured values assume P73615 each oxide material has a Poisson’s ratio of 0.27. Table 8 details the nominal compositions in atomic % (Zr as balance element) and the elastic modulus.

[0294] Table 8

[0295] The materials disclosed herein can be used for, but are not limited to, aero or industrial gas turbine engines, diesel and gasoline engine components, industrial furnace components, erosion resistant coatings for rocket nozzles, exhaust manifolds, carbon fiber wheel rims, coatings on luxury components such as clasps or buttons, or in other general commercial, luxury, or industrial applications.

Claims

P73615Claims1. A composition comprising a majority atom% zirconium dioxide based on total cation content, comprising zirconium dioxide in cubic and / or tetragonal phase, and having a bandgap of less than or equal to 4eV.

2. The composition of claim 1, wherein L<90 or C>5 on the CIE LCH scale.

3. The composition of claim 1, wherein at least 50% phase fraction of the zirconium dioxide is in the cubic and / or the tetragonal phase.

4. The composition of claim 1, having a bandgap of less than or equal to 3.6 eV.

5. The composition of claim 1, selected from oxides of (in atom%)X2: Cr: 0.01-20.0, Y: 5-25;X3: Mn: 0.01-20.0, Y: 5-25;X4: Ti: 0.01-20.0, Y: 5-25;X5: Mg: 0.01-20.0, Y: 5-25;X6: Mn: 0.01-20.0, Y: 5-25;X7: Ni: 0.01-20.0, Y: 5-25;X8: V: 0.01-20.0, Y: 5-25;X9: Al: 0.01-20.0, Mn: 0.01-20.0, Y: 5-25;XI 1: Mg: 0.01-20.0, Mn: 0.01-20.0, Y: 5-25;X12: Ni: 0.01-20.0, Ti: 0.01-20.0, Y: 5-25;X15: Fe: 0.01-20.0, Y: 5-25;X16: Fe: 0.01-20.0, Gd: 0.01-20.0, Ti: 0.01-20.0, Y: 5-25;X17: Ce: 0.01-20.0, Gd: 0.01-20.0, Y: 5-25;X21: Nd: 0.01-20.0, Y: 5-25;X24: Er: 0.01-20.0, Y: 5-25;X25: Dy: 0.01-20.0, Y: 5-25;X26: Yb: 0.01-20.0, Y: 5-25;X29: Nd: 0.01-20.0, V: 0.01-20.0, Y: 5-25;X30: Cr: 0.01-20.0, V: 0.01-20.0, Y: 5-25;X32: Ce: 0.01-20.0, Gd: 0.01-20.0, La: 0.01-20.0, Yb: 0.01-20.0, Y: 5-25;P73615X33: Fe: 0.01-20.0, Mg: 0.01-20.0, Y: 5-25;X44: Er: 0.01-20.0, Nd: 0.01-20.0, Y: 5-25;X45: Al: 0.01-20.0, Mg: 0.01-20.0, Y: 5-25;X46: Ce: 0.01-5, Dy: 0.01-5, Gd: 0.01-5, La: 0.01-5, Mg: 0.01-5, Nd: 0.01-5, Ni:.01-5, Sm: 0.01-5, Y: 5-25;X48: Dy: 0.01-20, Nd: 0.01-20, Ti: 0.01-20, Yb: 0.01-20, Y: 5-25;X50: Ce: 0.01-5, Er: 0.01-10, Dy: 0.01-5, La: 0.01-5, Mg: 0.01-5, Yb: 0.01-5, Y: 5-25;X51: Al: 0.01-25, Co: 0.01-25, Y: 5-25;X52: Ho: 0.01-15, Y: 1-25;X53: In: 0.01-15, Y: 1-25;X54: Pr: 0.01-15, Y: 1-25;X55: Tb: 0.01-15, Y: 1-25;X56: Tm: 0.01-15, Y: 1-25;X57: Eu: 0.01-15, Y: 1-25;X58: Lu: 0.01-15, Y: 1-25;X59: Th: 0.01-15, Y: 1-25;Y15: Cr: 0.01-5, Er: 0.01-5, Eu: 0.01-5, Fe: 0.01-5, Ho: 0.01-5, La: 0.01-5, Mg: 0.01-, Mn: 0.01-5, Nd: 0.01-5, Ni: 0.01-5, Pr: 0.01-5, Si: 0.01-5, Sm: 0.01-5, Sn: 0.01-5, Tb:.01-5, Tm: 0.01-5, Ti: 0.01-5, Yb: 0.01-5;Y18: Cr: 0.01-5, Er: 0.01-5, Eu: 0.01-5, Fe: 0.01-5, Ho: 0.01-5, La: 0.01-5, Mg: 0.01-0, Mn: 0.01-10, Nd: 0.01-5, Ni: 0.01-5, Sm: 0.01-5, Ti: 0.01-5, Yb: 0.01-5;Y22: Ca: 0.01-20, Y:l-25;Y23: Ce: 0.01-20, Y:l-25;Y46: Er: 0.01-5, Fe: 0.01-5, La: 0.01-5, Sm: 0.01-5, Sn: 0.01-5, Ti: 0.01-5, Yb: 0.01-5;Y47: Cr: 0.01-5, Er: 0.01-5, Fe: 0.01-5, La: 0.01-5, Mg: 0.01-10, Mn: 0.01-10, Nd:.01-5, Ni: 0.01-10, Sm: 0.01-5, Ti: 0.01-5, Yb: 0.01-5;Y48: Er: 0.01-5, Fe: 0.01-10, Mg: 0.01-10, Mn: 0.01-10, Nd: 0.01-5, Ni: 0.01-5, Sm:.01-5, Ti: 0.01-5, Yb: 0.01-5;Y56: Fe: 0.01-10, Hf: 0.01-10, Mg: 0.01-10, Ti: 0.01-10;Y59: Dy: 0.01-15, Er: 0.01-10, Fe: 0.01-15, Lu: 0.01-10, Mg: 0.01-10, Ti: 0.01-15;Y60: Dy: 0.01-15, Er: 0.01-10, Fe: 0.01-15, Lu: 0.01-15, Mg: 0.01-10, Ti: 0.01-10;Y62: Ce: 0.01-10, Dy: 0.01-10, Ti: 1-20;Y65: Er: 0.01-15, Fe: 0.01-15, Hf: 0.01-10, Lu: 0.01-15, Mg: 0.01-10, Ti: 0.01-15;Y68: In: .01-5, Mn: .01-3, Y: .01-25;P73615Y69: In: .01-15, Mn: .01-15, Y: .01-25;Y70: In: .01-10, Mn: .01-5, Y: .01-25;Y74: Fe: 1-10, La: 1-5, Y: 1-25;Y75: Ce: 0.01-5, Dy: 0.01-5, Fe: 0.01-10, Hf: 0.01-5, La: 0.01-5, Mg: 0.01-10, Y: 0.01-5, Yb: 0.01-5;Y76: Ce: 1-15, Dy: 0.01-5, La: 0.01-5, Mg: 0.01-5, Ti: 0.01-25, Y: 0.01-5, Yb: 0.01-5;Y77: Ce: 1-10, Dy: 0.01-5, Fe: 0.01-15, La: 0.01-5, Mg: 0.01-5, Y: 0.01-5, Yb: 0.01-5;Y78: Al: 1-5, Ce: 1-10, Dy: 0.01-5, Fe: 0.01-15, La: 0.01-5, Mg: 0.01-5, Ti: 0.01-15, Y: 0.01-5, Yb: 0.01-5;Y79: Ce: 1-10, Dy: 0.01-5, Fe: 0.01-10, Hf: 0.01-5, La: 0.01-5, Mg: 0.01-10, Ti: 0.01- 15, Y: 0.01-5, Yb: 0.01-5;Y82: Ce: 1-10, Gd: 0.01-5, La: 0.01-5, Mg: 0.01-10, Ti: 0.01-10, Yb: 0.01-5;Y83: Ce: 1-10, Gd: 0.01-5, La: 0.01-5, Mg: 0.01-10, Ti: 0.01-10, Y: 0.01-5, Yb: 0.01- 5; andY84: Ce: 1-10, Fe: 0.01-10, Gd: 0.01-5, Hf: 0.01-5, La: 0.01-5, Mg: 0.01-10, Ti: 0.01- 20, Yb: 0.01-5; each composition further comprising up to 10 atom% Hf, and up to 10 at% total impurities, the balance being Zirconium Dioxide.

6. A coated surface comprising at least a first coating thereon, wherein the first coating comprises a majority atom% zirconium dioxide based on total metal content, and has a bandgap of less than or equal to 4eV.

7. The coated surface of claim 6, having a furnace cycle lifetime of greater than 100 cycles.

8. The coated surface of claim 6, having a furnace cycle lifetime at least 50% of the cycles of a surface coated with 8YSZ.

9. The coated surface of claim 6, having a sand corrosion penetration less than 200% of the penetration depth of a surface coated with 8YSZ.P7361510. The coated surface of claim 6, having an average coefficient of thermal expansion between 8x106 / °C and 15x106 / °C when measured from 20°C to 1350°C.

11. The coated surface of claim 6, having a thermal diffusivity less than 125% of the thermal diffusivity of a surface coated with 8YSZ.

12. The coated surface of claim 6, having an elastic modulus between 10 GPa and 50 GPa in the as-deposited condition or between 50 GPa and 150 GPa after thermal cycling above 1000°C.

13. A coated surface comprising at least a first coating thereon, and at least a second coating over the first coating; wherein at least one of the first and second coatings comprises a majority atom% zirconium dioxide based on total metal content, and has a bandgap of less than or equal to 4eV ; and wherein a difference in color between the first and second coatings is AE>1 or AH>2.5 degrees based on the CIE LCH scale.

14. The coated surface of claim 13, wherein each of the first coating and the second coating (a) comprises a majority atom% zirconium dioxide based on total metal content of the respective coating, and (b) has a bandgap of less than or equal to 4eV.

15. The coated surface of claim 13, wherein the color difference AE is AE>2.5.

Images