17 results about "Secondary phase" patented technology

This invention belongs to the technical field of dielectric energy storage ceramic materials, and relates to a NaNbO3-based ceramic material with high energy storage density and efficiency and its preparation method. The chemical formula of the NaNbO3-based ceramic material is: (1- x NaNbO3- x Bi(Ni 0.2 Mg 0.2 Zr 0.1 Ta 0.2 Hf 0.2 The preparation method for NaNbO3 includes: mixing Na2CO3, Nb2O5, Bi2O3, NiO, MgO, ZrO2, Ta2O5, and HfO2, then adding zirconium oxide microspheres and alcohol, stirring, and drying to obtain a mixed powder; ball milling the pre-calcined powder and drying it again; pressing the dried powder into sheets; and sintering the pressed sheets to obtain NaNbO3-based ceramics. This invention uses a solid-state method to prepare ceramics. When the doping amount is 0.20 mol, a secondary phase appears in the ceramic sample; compared with pure NaNbO3, the energy storage efficiency is increased by about 30 times; when the doping amount is 0.10 mol, the energy storage density of NN-0.1BM5 is 5.1 J·cm⁻¹. ‑3 The energy storage efficiency is 94.0%.

This invention provides a tungsten-nickel-iron alloy with dual strengthening based on a molybdenum carrier and a secondary phase, and its preparation method, relating to the field of high-density tungsten-based alloy technology. The preparation method of the tungsten-nickel-iron alloy of this invention includes the following steps: S1: Preparation of composite microparticles: Combining secondary phase powder with molybdenum powder to obtain composite microparticles with secondary phase powder adhering to the surface or encapsulating it internally; S2: Mixing: Mixing the composite microparticles with tungsten powder, nickel powder, and iron powder in a specified ratio to form a mixed powder; S3: Sintering: Pressing the mixed powder into shape, and then sintering it in the liquid phase at a temperature of 1460-1550℃ for 30-120 minutes. This invention creatively designs a "composite-carrying-solution" technical route, using molybdenum particles as a carrier to introduce secondary phase particles into the interior of tungsten particles and the grain boundaries of the tungsten-molybdenum solid solution, enabling the tungsten-nickel-iron alloy to obtain tungsten-molybdenum solid solution strengthening and secondary phase dispersion strengthening, significantly improving the high-temperature strength, resistance to plastic deformation, self-sharpening properties, and penetration properties of the tungsten-nickel-iron alloy.

The application provides a heat treatment method for improving the tensile property of TC4 titanium alloy, and comprises the following steps: placing a treated TC4 titanium alloy sample in a heat treatment furnace to heat to below a beta phase transition temperature for solid solution and heat preservation; then, cooling to a certain temperature in the furnace according to a set cooling speed, and immediately water quenching; placing the quenched sample in the heat treatment furnace again to heat to below the beta phase transition temperature for aging and heat preservation for a period of time, and then cooling; the TC4 titanium alloy sample is made by plasma arc deposition and synchronous rolling additive manufacturing. In conclusion, the application combines the characteristics of subcritical annealing for regulating primary phase and large-scale microstructure and solid solution and aging for regulating secondary phase and small-scale microstructure, and the microstructure obtained after heat treatment comprises equiaxed primary alpha, discontinuous grain boundary alpha, secondary phase and alpha / beta interface phase, so that the tensile property of the TC4 titanium alloy is significantly improved.

This hot-rolled steel sheet has a predetermined chemical composition, in a microstructure at a ¼ position of a sheet thickness in a sheet thickness direction from a surface, by area ratios, a primary phase is 95.00% to 98.00% of bainite, a secondary phase is 2.00% to 5.00% of tempered martensite, an average grain size of the secondary phase is 1.5 μm or less, a pole density in a (110)<112> orientation is 3.0 or less, an average grain size of an iron-based carbide is 0.100 μm or less, in a microstructure from the surface to a 1 / 16 position of the sheet thickness in the sheet thickness direction from the surface, a pole density in a (110)<1-11> orientation is 3.0 or less, and a tensile, strength TS is 980 MPa or more.

This invention relates to a method for enhancing the corrosion resistance of magnesium-lithium alloys by inducing secondary phase reconstruction and solute redistribution through heat treatment, belonging to the field of metallic materials and their corrosion protection technology. The invention involves sample encapsulation and protection, thermal homogenization, and high-temperature heat treatment of a magnesium-lithium alloy containing multiple secondary phases. The heat treatment induces secondary phase reconstruction and solute redistribution, optimizing the microstructure and local electrochemical differences of the magnesium-lithium alloy containing multiple secondary phases. This results in the formation of a continuously distributed network of (Ca,Y)₂Mg₆Zn₃ phases and other uniformly distributed granular secondary phases within the matrix, significantly hindering the propagation of filamentous corrosion. This invention achieves solute redistribution and secondary phase continuity by controlling the partial dissolution of the high-potential secondary phase and its interaction with other secondary phases, thereby improving overall corrosion resistance. The process is highly applicable, simple and adjustable, cost-controllable, and easy to industrialize.

The rare earth sintered magnet has: a main phase which satisfies the general formula (Nd, Pr, RH, R)-Fe-B-M when RH is an element including at least one of Dy and Tb, R is one or more rare earth elements other than Nd, Pr, Dy, and Tb, and M is one or more elements selected from Ga, Al, Cu, and Co, and which contains crystal grains based on an Nd2Fe14B crystal structure; and a secondary phase. The main phase has a core part and a shell part, and when the Nd concentration in the core part is CNd and the Pr concentration is CPr, the main phase has a first main phase in which CNd > CPr and a second main phase in which CNd < CPr. The core portion of the first main phase is higher than the core portion of the second main phase in terms of the concentration of the heavy rare earth element RH. The first main phase is mixed with the second main phase. The sub-phase has a first sub-phase and a second sub-phase, the main component of which is an oxide phase represented by (Nd, Pr, RH, La, Sm)-O containing element M as a trace component. The concentration of the element M in the second sub-phase is higher than that in the first sub-phase.

a polycrystalline ceramic solid having a primary phase with the general composition (1-y)Pb a (Mg b Nb c )O 3‑e +yPb a Ti d O3, wherein 0.055≤y≤0.065; 0.95≤a≤1.02; 0.29≤b≤0.36; 0.63≤c≤0.69; 0.9≤d≤1.1; 0≤e≤0.1 and optionally one or more secondary phases, wherein for each cross section through the solid the area proportion of secondary phases based on the arbitrary cross sectional area through the solid is less than or equal to 0.5% or wherein the solid is free of secondary phases. Furthermore, an electrode having the ceramic solid and a device having the electrode are given and furthermore a method for manufacturing the solid and the electrode.

The invention provides a processing method of a high-purity copper target material, which comprises the following steps of: carrying out plastic processing on a high-purity copper target blank to obtain a deformed copper target blank, sequentially carrying out first-stage annealing and second-stage annealing on the deformed copper target blank, and then machining to obtain a finished product of the high-purity copper target material. According to the machining method provided by the invention, after the copper target material is subjected to plastic machining, two-stage annealing treatment is carried out, the target material still keeps a high-quality microstructure through precise control over the annealing process and balance of internal stress of the target material, and the target material still can keep high dimensional precision, low flatness and high parallelism after being machined such as cutting; therefore, the sputtering stability of the target material is improved, and the coating quality is improved.

The application discloses a method for preparing a high-temperature alloy rod with high compactness and uniformly distributed grains, and belongs to the technical field of high-temperature alloy rod processing. The application finds a hole closure interval by studying Thermo-Span low-expansion high-temperature alloy hot deformation parameters, makes the holes closed through high-temperature large deformation, makes the rod fully recrystallized through multi-fire free forging, obtains a uniform equiaxed fine-grain structure, and the grain size is 7-8 levels, which provides a nucleation position for subsequent secondary phase precipitation and contributes to the strengthening alloy.

A rare earth sintered magnet (1) has: a main phase (10) that satisfies the general formula (Nd, Pr, R)-Fe-B-M and contains crystal grains based on an Nd2Fe14B crystal structure, where R is one or more rare earth elements selected from the group consisting of Nd and Pr, and M is one or more elements selected from the group consisting of Ga, Al, Cu, and Co; and a sub-phase (20) formed between the main phases. The main phase has a core part and a shell part covering the core part. When the Nd concentration in the core portion is CNd and the Pr concentration in the core portion is CPr, the main phase has a first main phase (11) in which CNd > CPr and a second main phase (12) in which CNd < CPr. The first main phase is mixed with the second main phase. The sub-phase has a first crystalline sub-phase (21) and a second crystalline sub-phase (22), the main component of which is an oxide phase represented by (Nd, Pr, R)-O containing element M as a trace component. The concentration of the element M in the second pair is higher than that in the first pair.

Rare earth sintered magnets (1) possess the following characteristics: when R is set as one or more rare earth elements selected from Nd and Pr, they satisfy the general formula (Nd, Pr, R)-Fe-B, including Nd2Fe. 14 B has a crystal structure consisting of a main phase (10) with basic grains and a secondary phase (20) existing between multiple main phases (10). The main phase (10) has a core (11c, 12c) and a shell (11s, 12s) covering the core (11c, 12c). When the concentration of Nd in the core (11c, 12c) is set to CNd and the concentration of Pr in the core (11c, 12c) is set to CPr, the main phase (10) has a first main phase (11) with CNd > CPr and a second main phase (12) with CNd < CPr. The first main phase (11) and the second main phase (12) are mixed. Heavy rare earth elements are present on at least a portion of the surface of the first main phase (11) and the second main phase (12).

The invention provides a preparation method of a broadband gap perovskite thin film with homogeneous phase distribution and a rubidium component, the perovskite thin film and a perovskite solar cell. The method comprises the following steps: obtaining a perovskite precursor solution containing a rubidium component; melamine hydriodate is used as an additive to be mixed with the perovskite precursor solution to form a film forming solution, and the melamine hydriodate is used for inhibiting secondary phase precipitation caused by rubidium component enrichment in the crystallization process; and coating the film forming liquid on the surface of a substrate, and performing crystallization treatment to form the perovskite thin film.

The application belongs to the technical field of dielectric materials, and provides a bismuth-based perovskite ceramic with a self-absorption doping strategy and a preparation method.The chemical formula of the bismuth-based perovskite ceramic is (1-x)(0.7BiFeO3-0.3SrTiO3)-xBi2Ti2O7, wherein 0x≤0.08.In the embodiment of the application, Bi2Ti2O7 (BTO) secondary phase which is prone to appear in bismuth-based perovskite is used as a doping component to improve the dielectric breakdown strength of BiFeO3-SrTiO3 (BFST) solid solution ceramic.After twice solid-phase sintering, the BFST-BTO solid solution ceramic is formed by mixing and sintering again, and the incorporation of BTO improves the dielectric breakdown strength and energy storage density of the BFST-based ceramic, thereby providing a new strategy for improving the dielectric breakdown strength without introducing new elements, and having potential application value for improving the energy storage performance of other bismuth-based ceramics.

The invention provides a precise microstructure regulation and control method in a double-phase magnesium-lithium alloy spinning forming process, which comprises the following steps of: setting different spinning processes and initial state phase volume fractions according to orthogonal design, and obtaining a cross-scale microstructure evolution rule in the spinning process; establishing a primary phase and secondary phase precipitation kinetic model related to the spinning process, and determining a quantitative mapping relationship among spinning process parameters, an initial state phase volume fraction and a primary / secondary phase volume fraction; a phase dynamic recrystallization model related to the spinning process is established, and the quantitative incidence relation between spinning process parameters and the dynamic recrystallization fraction and the grain size is determined; and a machine learning framework is constructed, and according to the deviation between the predicted values of the primary / secondary phase and the phase microstructure of the component and the target quantity in the spinning forming process, the optimal process parameter domain is output in combination with machine learning algorithm adjustment and optimization. The method can solve the problems that an existing microstructure prediction model in the spinning forming process of the double-phase magnesium-lithium alloy is low in precision, and an accurate regulation and control method is lacked.

The present application relates to the field of additive technology, and particularly to a method for preparing high-performance dual-phase die steel based on non-equilibrium solidification rate and realizing performance improvement.The present application prepares dual-phase die steel spherical powder through PREP, and uses the dual-phase die steel spherical powder as raw material to prepare laser deposition parts through LDED technology.The present application realizes primary phase change by using non-equilibrium rapid cooling of prepared powder, and realizes secondary phase change by changing phase content of deposited parts, so as to prepare dual-phase die steel, wherein the phase composition of formed parts in the additive manufacturing process is derived from genetic characteristics of metal powder.The technology prepares spherical dual-phase die steel powder and additive manufacturing parts thereof through PREP and LDED respectively, and adjusts phase content of the dual-phase die steel by changing laser power in the LDED process.The present application has simple and controllable process, and the obtained product has superior performance and is convenient for industrial application.

a polycrystalline ceramic solid having a primary phase with the general composition (1-y)Pb a (Mg b Nb c )O 3‑e + yPb a Ti d O3, wherein 0.055 ≤ y ≤ 0.065; 0.95 ≤ a ≤ 1.02; 0.29 ≤ b ≤ 0.36; 0.63 ≤ c ≤ 0.69; 0.9 ≤ d ≤ 1.1; 0 ≤ e ≤ 0.1 and optionally one or more secondary phases, wherein for each cross section through the solid the area proportion of secondary phases based on the arbitrary cross sectional area through the solid is less than or equal to 0.5% or wherein the solid is free of secondary phases. Furthermore, an electrode having the ceramic solid and a device having the electrode are given and furthermore a method for manufacturing the solid and electrode.

The invention discloses olivine type microwave dielectric ceramic with a low dielectric constant, the chemical formula of the olivine type microwave dielectric ceramic is Mg2Si1-0. 75xAlxO4, and x is more than or equal to 0.04 and less than or equal to 0.16. The preparation method comprises the following steps: S1, weighing and proportioning raw material powder SiO2, Al2O3 and MgO according to the molar ratio of Mg2Si < 1-0.75 x > Al < x > O < 4 >; s2, the weighed original powder is mixed and added into a ball mill to be subjected to wet ball milling; s3, drying the slurry obtained by ball milling; pre-sintering the dried powder to obtain powder A; s4, adding a binder into the powder A, granulating, and forming to obtain a green body; and S5, the green body is sintered in the air atmosphere, and the Mg2Si1-0. 75xAlxO4 (x is larger than or equal to 0.04 and smaller than or equal to 0.16) ceramic is obtained. By introducing Al < 3 + > ions into an olivine structure, high-temperature sintering conditions required by densification of silicon-based olivine are effectively relieved, so that the sintering temperature of the microwave dielectric ceramic is reduced to 1300 DEG C or below, and the ceramic with a compact microstructure is obtained; the introduction of Al < 3 + > inhibits the appearance of a second phase of MgSiO3 in the sintering process, so that the ceramic has a low dielectric constant and a high quality factor at the same time.