29 results about "Tetragonal zirconia" patented technology

The invention relates to a micro-nano mullite reinforced zirconium oxide inorganic fiber, the phase of the micro-nano mullite reinforced zirconium oxide inorganic fiber is composed of two phases of tetragonal zirconium oxide and mullite, the fiber diameter is 0.1-1.5 [mu] m, and crystal phase stability, microstructure stability and fiber flexibility are maintained at the temperature from room temperature to high temperature of 1400 DEG C. The preparation method comprises the following steps: taking acidic aluminum sol, silica sol, zirconium sol and yttrium salt as metal sources, taking a high-molecular polymer as a spinning auxiliary agent, obtaining micro-nano mullite reinforced zirconium oxide precursor fibers through an electrostatic spinning technology, and carrying out heat treatment on the precursor fibers to obtain the mullite reinforced zirconium oxide inorganic fibers. The invention has the advantages of wide raw material source, cheap raw materials, stable system, good spinnability, high solid content, simple preparation process and the like. The prepared inorganic fiber has good high-temperature stability and flexibility in a wide temperature range from room temperature to high temperature of 1400 DEG C, and has application prospects in the fields of aerospace vehicle flexible heat insulation felts, high-temperature crystal growing furnaces and other high-temperature flexible heat insulation and heat preservation.

The invention relates to the technical field of special ceramic products, in particular to ceramic capable of naturally forming cracks and a preparation method thereof, and solves the defects in the prior art. The ceramic comprises the following components: a matrix phase: aluminum oxide and tetragonal phase zirconium oxide; the biological template derivative phase is a carbonized bamboo fiber residual carbon network, the surface of the carbonized bamboo fiber residual carbon network is coated with a beta-silicon carbide quantum dot layer, and the residual carbon network is distributed in a radial density gradient manner; a reinforcing phase: beta-sialon whiskers; and the surface functional layer is an yttrium oxide stabilized yttrium aluminum garnet pinning phase and a pyrochlore type lanthanum zirconium oxide nano porous layer. According to the method, through accurate mapping of material components and process parameters (centrifugal force gradient, water vapor partial pressure and asymmetric cooling), synchronous optimization of crack morphology and mechanical properties is achieved, the mindset of'crack inhibition 'of traditional ceramics is broken through, and a new paradigm of'active crack design' is created.

The invention discloses a zirconia composite ceramic microbead and a preparation method thereof, and belongs to the technical field of zirconia ceramic microbeads. The zirconia composite ceramic microbeads are prepared from 80-90 parts by mass of yttrium-stabilized tetragonal phase zirconia powder, 5-10 parts by mass of alumina powder and 5-10 parts by mass of silicon carbide composite powder. Yttrium-stabilized tetragonal phase zirconia is used as a basic material, alumina and polycrystalline multi-granularity silicon carbide composite powder are used as auxiliary materials, the silicon carbide powder with high wear resistance and high corrosion resistance is used for improving the overall wear resistance and corrosion resistance of the composite ceramic microbead, and after the silicon carbide composite powder is added, the Vickers hardness and strength of the zirconia composite ceramic microbead are obviously improved; and the wear rate is greatly reduced, and the mass loss rate after strong acid solution soaking is greatly reduced. The prepared zirconium oxide composite ceramic microbead is excellent in wear resistance and good in corrosion resistance, meanwhile, the raw materials are wide in source, the preparation method is simple, and the good market prospect is achieved.

The application discloses a preparation method and application of a zirconium dioxide loaded iridium oxide nanocluster oxygen evolution electrocatalyst. A mixed solution of zirconium salt, amide solvent and organic acid is prepared, and the mixed solution is kept at 120 DEG C for 24 hours; after cooling, the white product is separated, washed and dried. Then, the product and iridium salt are dispersed in a mixed solution of tetrahydrofuran and water, and sodium nitrate and potassium nitrate aqueous solution are added under stirring; after stirring, rotary evaporation is carried out at 60 DEG C, and the greenish powder obtained after drying is vacuum dried at 60 DEG C for 12 hours; the greenish powder is kept in a muffle furnace at 450 DEG C for 30 minutes, and then cooled in air; the greenish powder is washed with deionized water and anhydrous ethanol for multiple times, and finally vacuum dried at 60 DEG C for 12 hours. The zirconium dioxide loaded iridium oxide material based on oxygen overflow stable tetragonal zirconia can be specially applied to an electrocatalyst for an oxygen evolution reaction in an acidic electrolyte, has excellent oxygen evolution reaction activity, follows a lattice oxygen mechanism in the reaction process, and can realize an oxygen overflow effect from tetragonal zirconia to iridium oxide nanoclusters to stabilize the catalyst.

This invention discloses a composite rare earth oxide co-stabilized zirconia ceramic microsphere and its preparation method, belonging to the technical field of zirconia ceramic microspheres. The zirconia ceramic microspheres are prepared from 80-90 parts by mass of tetragonal zirconia (ZrO2) powder, 0.5-1 parts by mass of alumina (Al2O3) powder, 5-10 parts by mass of yttrium oxide (Y2O3) powder, and 5-10 parts by mass of composite rare earth oxide powder. This invention uses tetragonal zirconia as the base material, adds yttrium oxide (Y2O3) as a stabilizer, and further adds composite rare earth oxides ytterbium oxide (Yb2O3) and nano-gadolinium oxide (Gd2O3). Yb2O3 serves as the second stabilizer, while Gd2O3 enhances the ferroelastic toughening effect of the ceramic. The combined effect of the two rare earth oxides increases the strength of the zirconia ceramic microspheres.

This invention relates to the field of medical ceramic materials technology, and more particularly to a method for preparing a zirconia-based medical composite ceramic material. The method includes: adjusting the target number of cycles in response to the slurry mixing state, or compensatingly adjusting the spray granulation process parameters based on slurry state parameters; determining whether the current batch of green bodies has a risk of closed pores based on the green body characteristics, and determining an adjustment feature point based on the actual shrinkage rate variation; stopping the sintering heating and adding a holding stage in response to the adjustment feature point, and determining the intermediate holding temperature and the holding stage duration; obtaining the sintered body phase to determine the tetragonal zirconia retention rate, and determining whether the sintering adjustment strategy matches the characteristics of the current batch of slurry based on the sintered body performance; and adjusting the intermediate holding temperature of subsequent sintering processes based on the tetragonal phase retention rate deviation in response to the sintered body performance. This invention improves the performance of ceramic implants by adjusting the sintering temperature curve based on the characteristics of zirconia-based powder.

This application discloses a method for preparing silver-tin oxide electrical contact material for magnetic latching relays, comprising the following steps: depositing indium oxide and tin oxide sequentially on the surface of silver powder by physical vapor deposition to obtain a coated powder, wherein the indium oxide content is 0.3~0.8wt%, the tin oxide content is 8~10wt%, and the balance is silver; mixing the coated powder, yttrium-stabilized tetragonal zirconium oxide, and trace additives to obtain a composite powder, wherein the trace additives are copper oxide or tungsten oxide, and the mass ratio of yttrium-stabilized tetragonal zirconium oxide to coated powder is (2~5):100; hot pressing the composite powder at 25~35MPa to obtain a blank, and holding it at that temperature for 1~2h; hot extrusion processing to process the blank into a rod; multi-pass drawing to produce a wire, and performing intermediate annealing treatment during the drawing process, with each annealing time being 1~2h. The electrical contact prepared by this method has high contact resistance stability and arc erosion resistance.

The invention provides zirconium oxide composite powder and a preparation method thereof, zirconium oxide ceramic and a dental prosthesis. The zirconium oxide composite powder comprises zirconium oxide matrix particles and cubic-phase zirconium oxide particles, the zirconium oxide matrix particles comprise monoclinic-phase zirconium oxide and tetragonal-phase zirconium oxide, and at least part of the cubic-phase zirconium oxide particles and the zirconium oxide matrix particles form an atomic-scale combined interface. The powder compounded in the manner is sintered, so that the reduced hardness can be obtained while the mechanical strength and toughness meeting the requirements of the dental restoration are obtained, the hardness matching property with jaw teeth is improved, and the pathological wear risk is reduced.

The present invention provides zirconia media, zirconia bearing balls, and methods for manufacturing the same, with improved wear resistance and durability. [Solution] (a) Made of a sintered body of ZrO2-Y2O3 zirconia, with a Y2O3 / ZrO2 molar ratio in the range of 2.5 / 97.5 to 3.2 / 96.8, (b) Al2O3 content in the range of 0.1% by mass to 30.0% by mass, (c) Contains 90% by volume or more of tetragonal zirconia, (d) Relative density of 95% or more, (e) Average crystal grain size in the range of 0.25 μm to 0.50 μm, (f) Minimum crushing load value Pmin(N) > 600 × D 2.0 (D is the average media diameter), (g) the Weibull coefficient of the crushing load is 10 or greater, and (h) the coefficient of variation of the media diameter is less than 6%. This is a zirconia-based media.

Sintered bead that has a crystalline composition, as percentages by weight based on the total weight of the crystalline phases: zircon<25%; 50%≤cubic zirconia+tetragonal zirconia≤95%, the cubic zirconia content being greater than 50%, the cubic zirconia content being the (cubic zirconia / (cubic zirconia+tetragonal zirconia) ratio by weight); 0≤monoclinic zirconia≤(10−0.2*tetragonal zirconia) %; 5%≤corundum≤50%; crystalline phases other than zircon, cubic zirconia, tetragonal zirconia, monoclinic zirconia and corundum<10%; and the following chemical composition, as percentages by weight based on the oxides: 34%≤ZrO2+HfO2, ZrO2+HfO2 being the remainder to 100%; HfO2≤4.0%; 0.5%≤SiO2≤14.1%; 4.5%≤Al2O3≤49.6%; 2.75%≤Y2O3≤22.8%; MgO≤5%; CaO≤2%; oxides other than ZrO2, HfO2, SiO2, Al2O3, MgO, CaO and Y2O3<5.0%.

The invention relates to a layer system (1) at least comprising (in wt.%) a metallic substrate (4), optionally a metallic adhesion promoter layer (7) on the substrate (4), and a ceramic base layer (10) made of partially stabilized, tetragonal zirconia, comprising Yttrium oxide, Ytterbium oxide, and Gadolinium oxide as stabilizers as well as a ceramic top layer (13) made of fully stabilized cubic zirconia on the ceramic base layer (10), wherein the proportion of stabilizers is between 17.5% and 25.5%.

To provide a zirconia sintered body that has high impact resistance even in a thin shape having a thickness of 0.5 mm or less, and also has high light-shielding property such that a member serving as a substrate is not visible therethrough.SOLUTION: A zirconia sintered body comprising a stabilizing element, niobium, manganese, and alumina, wherein a crystallite diameter calculated from an XRD peak attributed to the (111) plane of tetragonal zirconia is 25 nm or more and 100 nm or less.SELECTED DRAWING: Figure 1

Provided is at least one among: a zirconia sintered body that exhibits excellent transmission for near-infrared light and can be applied as a cover member that is thinner than conventional cover materials; and a production method therefor.　This yttrium-containing zirconia sintered body has an yttrium content of more than 2.0 mol%, an average grain size of less than 150 nm, and an average birefringence of 0.09 or less, and contains tetragonal zirconia as a main phase.

According to the present application, for various piezoelectric materials, a piezoelectric film having a crystal structure of a single crystal can be formed on the film structure of the present application. The film structure of the present application has: a substrate; a buffer film having a crystal structure of tetragonal zirconia formed on the substrate; a metal film containing a platinum group element epitaxially grown on the buffer film; and a film containing Sr(Ti 1‑x , Ru x )O3 (0≤x≤1) epitaxially grown on the metal film.

The application discloses a kind of tetragonal phase zirconium oxide / HA nano array bioactive composite coatings grown on zirconium alloy surface and method, belong to zirconium alloy surface treatment technical field, with Zr-2.5Nb alloy as anode, with pulse power constant voltage mode in containing calcium, phosphorus alkaline electrolyte Micro-arc oxidation reaction is carried out, voltage is 300-500V, Ca, P porous calcium stable tetragonal phase ZrO2 coating containing is generated on the surface of Zr-2.5Nb alloy, in 60-140 ℃ alkaline solution First hydrothermal reaction is carried out, then in containing calcium, phosphorus 60-140 ℃ alkaline mixed solution Second hydrothermal reaction is carried out, HA nano array bioactive coating is uniformly grown on the surface of tetragonal phase zirconium oxide coating, can effectively realize the modification to Zr-2.5Nb alloy surface, reach the purpose of promoting its bone integration ability and improving material mechanical property.

Stack (100) of electrochemical cells (301) containing: an electrochemical cell (301); and a manifold (200) supporting a base end (302) of the electrochemical cell (301); wherein the electrochemical cell (301) includes an electrically insulating support substrate (2) and a plurality of power generation units (11, 12, 13, 14) arranged on the support substrate (2), wherein a gas flow path (21) is provided in the support substrate (2); wherein each of the plurality of power generation units (11, 12, 13, 14) includes an anode (3), a cathode (6), and a solid electrolyte layer (4) disposed between the anode (3) and the cathode (6), which solid electrolyte layer includes a zirconium dioxide-based material as a main component; wherein in a power generation unit (11) on the base end side closest to the manifold (200) among the plurality of power generation units (11, 12, 13, 14), the solid electrolyte layer (4) includes a first region (41) covering within 3 µm of an anode-side surface and a second region (42) provided on the first region (41); wherein an intensity ratio of tetragonal zirconia to cubic zirconia in a Raman spectrum in the first region (41) is greater than an intensity ratio of tetragonal zirconia to cubic zirconia in the Raman spectrum in the second region (42); and wherein an intensity ratio of tetragonal zirconia to cubic zirconia in the Raman spectrum in the first region (41) is greater than an intensity ratio of tetragonal zirconia to cubic zirconia in the Raman spectrum in the solid electrolyte layer (4) of another power generation unit (12, 13, 14) of the plurality of power generation units (11, 12, 13, 14) other than the power generation unit (11) on the base end side.

Stack (10) of electrochemical cells (100) containing: a first separator (200); a second separator (200); and an electrochemical cell (100) arranged between the first separator (200) and the second separator (200), which electrochemical cell (100) contains an anode (110), a cathode (130) and a solid electrolyte layer (120), which solid electrolyte layer (120) is arranged between the anode (110) and the cathode (130) and contains a zirconium dioxide-based material as a main component, wherein the solid electrolyte layer (120) has a downstream part (120a) and an upstream part (120b), the downstream part (120a) being positioned on a downstream side in a flow direction (FG) of the fuel gas, which flows in a fuel flow channel (110S) between the anode (110) and the first separator (200), the upstream part (120b) being positioned on an upstream side in the flow direction (FG), wherein the downstream part (120a) includes a first region (a1) within 3 µm of an anode-side surface and a second region (a2) arranged between the first region (a1) and the cathode (130), wherein an intensity ratio (R1) of tetragonal zirconia to cubic zirconia in a Raman spectrum of the first region (a1) is greater than an intensity ratio (R2) of tetragonal zirconia to cubic zirconia in a Raman spectrum of the second region (a2), and wherein the intensity ratio (R1) of tetragonal zirconia to cubic zirconia in a Raman spectrum of the first region (a1) is greater than the intensity ratio of tetragonal zirconia to cubic zirconia in a Raman spectrum of the upstream part (120b).

Provided is a means capable of polishing an organic material at a high polishing speed and reducing the number of scratches after polishing. The polishing composition of the present invention contains zirconia particles and a dispersing medium, in which the zirconia particles contain at least one of tetragonal zirconia and cubic zirconia, and an average secondary particle size of the zirconia particles is less than 80 nm.

The invention relates to a coating system (1), comprising at least a metallic substrate (4), optionally a metallic bond coat layer (7) on the substrate (4), and a ceramic sub-layer (10) of tetragonal zirconia, comprising 3.5 wt% to 8.0 wt% yttrium oxide and 6.0 wt% to 8.0 wt% ytterbium oxide, and a ceramic top layer (13) of cubic zirconia on the ceramic sublayer (10).

The invention discloses an oxygen sensor and a preparation method of an oxygen sensing substrate. The oxygen sensor comprises a substrate, the substrate is provided with a zirconium oxide layer, and the zirconium oxide layer comprises the following components in percentage by weight: 59.9 wt% to 67.5 wt% of Zr, 5.23 wt% to 6.6 wt% of Y, 0.05 wt% to 1.21 wt% of Nb, 0.44 wt% to 3.57 wt% of Ba, 0 to 0.46 wt% of Si and 0.18 wt% to 2.77 wt% of Al; and the phase of the zirconium oxide layer comprises the following components in percentage by weight: 88.5 to 98.5 percent of tetragonal phase zirconium oxide, 0.83 to 6.7 percent of barium aluminate, 0 to 3.55 percent of mullite phase and the balance of monoclinic phase zirconium oxide. The substrate of the oxygen sensor provided by the invention has relatively good mechanical properties.

The invention discloses an erbium-stabilized zirconium oxide toughened aluminum oxide composite material and a preparation method thereof, and relates to the technical field of high-performance structural ceramics, the erbium-stabilized zirconium oxide toughened aluminum oxide composite material comprises an aluminum oxide matrix and a zirconium oxide toughening phase, the volume fraction of the zirconium oxide toughening phase is 10-30 vol%, the zirconium oxide toughening phase is an erbium-stabilized tetragonal phase, and the volume fraction of the erbium-stabilized tetragonal phase is 10-30 vol%. Wherein the molar percentage of erbium oxide is 1-5 mol%; according to the composite material, erbium ions are introduced to serve as a stabilizer of zirconium oxide, effective stability of tetragonal phase zirconium oxide is achieved, meanwhile, the material is endowed with excellent fluorescence performance and can be used for stress distribution in-situ monitoring, uniform doping of erbium elements is ensured by adopting a coprecipitation method in the preparation process, and high-energy ball milling and high-temperature sintering processes are combined, so that the composite material is prepared. The density and the grain boundary bonding strength are remarkably improved, so that the material has high strength, high fracture toughness and good optical response characteristics, and is suitable for performance tracking and failure analysis of precision ceramic parts in a complex service environment.

This application provides zirconia composite ceramics, their preparation methods, and applications, comprising the following phases by weight percentage: 92 wt.%–99 wt.% yttrium-stabilized tetragonal zirconia and 1 wt.%–8 wt.% titanium-based composite oxide; wherein the general molecular formula of the titanium-based composite oxide includes Ti. (1‑x‑y) M x A y O (2‑x‑0.5y) x = 0 or 0.01 ≤ x ≤ 0.1, y = 0 or 0.01 ≤ y ≤ 0.1, and x and y are not both 0. This zirconia composite ceramic has high color purity, strong visual impact, and excellent drop resistance, making it suitable for providing highly recognizable electronic device housing components.

The present invention provides zirconia media, zirconia bearing balls, and methods for manufacturing the same, with improved wear resistance and durability. [Solution] (a) Made of a sintered body of ZrO2-Y2O3 zirconia, with a Y2O3 / ZrO2 molar ratio in the range of 2.5 / 97.5 to 3.2 / 96.8, (b) Al2O3 content in the range of 0.1% by mass to 30.0% by mass, (c) Contains 90% by volume or more of tetragonal zirconia, (d) Relative density of 95% or more, (e) Average crystal grain size in the range of 0.25 μm to 0.50 μm, (f) Minimum crushing load value Pmin(N) > 600 × D 2.0 (D is the average media diameter), (g) the Weibull coefficient of the crushing load value is 10 or greater, and (h) the coefficient of variation of the media diameter is less than 6%. This is a zirconia-based media.

Provided is a zirconia sintered body that has high shock resistance while having a thin shape which has a thickness of 0.5 mm or less, and that is such that a member serving as a base has a high light blocking effect achieving opaqueness. The zirconia sintered body contains a stabilizing element, niobium, and alumina and also contains iron, cobalt, and zinc as pigment components, and has a crystallite diameter of 25-100 nm belonging to the (111) plane of tetragonal zirconia as calculated from peaks in XRD.

An oxygen sensor and a preparation method for an oxygen sensor substrate. The oxygen sensor comprises a substrate, the substrate having a zirconia layer, and the zirconia layer comprising, in terms of elements: Zr, a trivalent element, Nb, and Al. The phases of the zirconia layer comprise 96 wt％-99.7 wt％ of tetragonal zirconia, the remainder is monoclinic zirconia. In the tetragonal zirconia, the ratio of the molar content of a trivalent element oxide to the total molar content of the zirconia, the trivalent element oxide, and niobium oxide is a, satisfying a＝4.5 mol％-5.5 mol％. The ratio of the molar content of the niobium oxide to the total molar content of the zirconia, the trivalent element oxide, and the niobium oxide is b, satisfying a-b＝4 mol％-5 mol％, and the trivalent element comprising one or more of Y, Sm, Er, Sc and Nd.

The invention discloses a composite rare earth oxide co-stabilized zirconia ceramic microbead and a preparation method thereof, and belongs to the technical field of zirconia ceramic microbeads. The zirconia ceramic microbeads are prepared from 80-90 parts by mass of tetragonal phase zirconia (ZrO2) powder, 0.5-1 part by mass of alumina (Al2O3) powder, 5-10 parts by mass of yttrium oxide (Y2O3) powder and 5-10 parts by mass of composite rare earth oxide powder. Tetragonal phase zirconia is used as a base material, yttrium oxide (Y2O3) is added as a stabilizer, composite rare earth oxide ytterbium oxide (Yb2O3) and nano gadolinium oxide (Gd2O3) are further added, the Yb2O3 is used as a second stabilizer, the Gd2O3 can enhance the ferroelastic toughening effect of ceramics, and the two rare earth oxides are compounded to act together to enhance the strength of the zirconia ceramic microbeads.

To provide a zirconia sintered body that has high impact resistance even in a thin shape having a thickness of 0.5 mm or less, and also has high light-shielding property such that a member serving as a substrate is not visible therethrough.SOLUTION: A zirconia sintered body comprising a stabilizing element, niobium, alumina, and iron, cobalt, and zinc as pigment components, wherein a crystallite diameter calculated from an XRD peak attributed to the (111) plane of tetragonal zirconia is 25 nm or more and 100 nm or less.SELECTED DRAWING: Figure 1

To provide: zirconia-based media with improved wear resistance and durability; a zirconia bearing ball; and a method for manufacturing the same.SOLUTION: The zirconia media (a) comprise a sintered compact of a ZrO2-Y2O3-based zirconia, wherein: a molar ratio of Y2O3 / ZrO2 is in a range of 2.5 / 97.5 or more and 3.2 / 96.8 or less; (b) a content of Al2O3 is in a range of 0.1 mass% or more and 30.0 mass% or less; (c) 90 vol.% or more of tetragonal zirconia is contained; (d) a relative density is 95% or more; (e) an average crystal grain size is within a range of 0.25 μm or more and 0.50 μm or less; (f) a minimum value of the crushing load is Pmin(N)>600×D2.0 (where D is an average value of a media diameter); (g) a Weibull coefficient of the crushing load value is 10 or more; and (h) a coefficient of variation of the media diameter is less than 6%.SELECTED DRAWING: Figure 1

Provided is a zirconia sintered body that has a high impact resistance even as a thin shape with a thickness of 0.5 mm or less, and has a high light-shielding property in which a member serving as a substrate does not show through. This zirconia sintered body includes a stabilizing element, niobium, manganese, and alumina, wherein the crystallite diameter calculated from an XRD peak that is attributed to the (111) plane of tetragonal zirconia is 25 nm to 100 nm.