31results about How to "Stable and reliable process conditions" patented technology

The invention provides a method for preparing a nano silver paste. The method includes step A, a reducing agent and a dispersing agent are dropwise added in a silver nitrate solution and stirred; step B, the solution obtained through the step A is subjected to centrifugation to obtain nano silver particles with upper layers as mixed solutions and lower layers as sedimentation; step C, the nano silver particles separated through the step B is cleaned by deionized water and subjected to flocculation by a electrolyte solution, and nano silver particles capable of being subjected to centrifugation are re-precipitated; step D, the nano silver particles are subjected to cleaning, flocculation and centrifugation for a plurality of times to obtain a water-soluble nano silver paste; and step E, the nano silver paste is applied to a chip and a substrate surface to be interconnected, and the interconnected chip and substrate surface is heated in a hot air work bench or a stove to form a sintering joint.

The invention relates to a nanosilver / epoxy resin composite thermal interface material and a preparation method thereof. The nanosilver / epoxy resin composite thermal interface material is prepared through the following method: (1) adding silver salt to a complexing agent, and performing uniform mixing so as to obtain a silver complex; and sequentially adding the silver complex, a reducing agent containing two aldehyde groups and an imidazole curing agent to epoxy resins, and performing uniform mixing so as to obtain mixed sol; and (2) pouring the mixed sol obtained in the step (1) to a mold, placing the mold in a heating box, performing heating under the constant temperature of 50-70 DEG C for 2-6h, then performing temperature rise to 90-130 DEG C, performing heating under constant temperature for 2-6h, so as to obtain the nanosilver / epoxy resin composite thermal interface material. According to the nanosilver / epoxy resin composite thermal interface material provided by the invention, the heat conductivity can reach 3.25W / mK, the interface heat-transfer efficiency is greatly improved, interface thermal resistance is effectively reduced, few defects exist and the properties are favorable.

The invention discloses inorganic aluminate luminescent microcrystalline glass and a preparation method thereof. The inorganic aluminate luminescent microcrystalline glass is a substance shown as a chemical formula, namely, X SrO-Y Al2O3-Z SiO2-R Pr2O3, wherein X, Y, Z and R are molar fractions; X is more than or equal to 25 and less than or equal to 40; Y is more than or equal to 25 and less than or equal to 40; Z is more than or equal to 25 and less than or equal to 50; and R is more than or equal to 0.1 and less than or equal to 2. The preparation method comprises the following steps of: grinding strontium carbonate, alumina, silicon dioxide and praseodymium oxide serving as raw materials and mixing; fusing at the temperature of between 1,550 and 1,650 DEG C and molding the raw materials to obtain glass; and thermally treating the molded glass at the temperature of between 800 and 1,150 DEG C in a reducing atmosphere for 8 to 12 hours so as to obtain the inorganic aluminate luminescent microcrystalline glass. The inorganic aluminate luminescent microcrystalline glass has a relatively wide excitation spectrum in a blue light range, pure luminescent chromaticity, a stable physical property, a simple preparation method and low cost.

The invention provides bimodal distribution nano-silver paste serving as a thermal interface material and a preparation method of the bimodal distribution nano-silver paste. The preparation method comprises the following steps of mixing small-grain-diameter nano-silver particles with grain diameters of 5-20 nanometers, large-grain-diameter nano-silver particles with grain diameters of 30-150 nanometers and ultra-pure water according to a certain mass proportion of 4:1-1:1; mechanically stirring the mixture; ultrasonically dispersing the mixture and centrifuging the mixture; and removing an upper layer of solution so as to obtain the bimodal distribution nano-silver paste. The invention also provides a preparation method for the small-grain-diameter nano-silver particles with the grain diameters of 5-20 nanometers and the large-grain-diameter nano-silver particles with the grain diameters of 30-150 nanometers. Compared with unimodal distribution nano-silver paste and tin-lead solder, the bimodal distribution nano-silver paste which is prepared by the method has high heat conduction performance and high sintering structural stability. The preparation method is simple, preparation technological conditions are stable and reliable, the environment cannot be polluted, and the bimodal distribution nano-silver paste can be used industrially.

The invention discloses a rare earth phosphate nano-phosphor and a preparation method thereof. A synthesis method comprises the steps of taking polyphosphoric acid, nitric acid and rare earth nitrate as raw materials, taking sodium oleate as surfactant and performing hydrothermal treatment on precursors at 100 to 180 DEG C to obtain oil-soluble phosphor. According to the difference of rare earth ions contained, the phosphor emits visible red, green or light red light under the irradiation of 254nm-wavelength ultraviolet rays of a low-pressure mercury lamp. The obtained phosphor is white powder with small particle size, uniform size distribution and high luminescent intensity, and as the surfaces of phosphor particles adsorb hydrophilic groups COO- at one end of oleate ions while organic long chains at the other end of the oleate ions are oleophylic groups, the nano-phosphor has good dispersity in organic solvent and can be dispersed in the organic solvent to form transparent sol.

The invention relates to a method for preparing spherical silver powder by using a hydroxymethyl amino condensation product as a dispersant. The obtained superfine spherical silver powder can be used for preparing conductive slurry in the electronic industry. The method comprises the following steps: (1) preparing the hydroxymethyl amino condensation product serving as the dispersant by using an amine compound and formaldehyde solution; and (2) preparing mixed solution of a reducing agent and the dispersant, adjusting the pH value of the mixed solution of the reducing agent and the dispersantby using aqueous ammonia or nitric acid solution, adding silver nitrate solution into the mixed solution consisting of the reducing agent and the dispersant while stirring, and after the reaction is completed, standing, filtering, washing and drying the reaction product to obtain the superfine silver powder with different granularity from 0.5 to 3 microns.

The invention discloses a zinc-nickel battery negative electrode material. The invention uses an alkaline zinc carbonate / carbon composite material as the negative electrode active material of the zinc-nickel battery to prepare a zinc-nickel battery negative electrode and a Ni positive electrode structure containing the alkaline zinc carbonate / carbon composite material. Into a soft NiZn battery. The test results show that when the material is used as a battery negative electrode material, the overall electrochemical performance of the electrode and the battery containing the material is improved. The prepared pouch battery has high energy density, Coulombic efficiency and long cycle life.

The invention discloses a preparation method of a cathode material for a nickel-zinc battery. The method comprises large-scale modification of a carbon material, so that the surface has an oxygen-containing group, and the carbon material has good dispersity in water or an organic solvent. The invention further discloses a preparation method of an Ni(OH)<2> / carbon composite material. The material is applied to a positive electrode and a Zn negative electrode to construct a soft package NiZn battery. A test result shows that the material improves the electric contact performance of the electrodes when used as an electrode material, so that the overall electrochemical properties of the electrodes and the battery including the material are improved.

The invention provides a preparation method for nanometer calcium hydroxide. According to the preparation method, quick lime powder, organic solvent, and water are uniformly mixed according to a certain ratio, so that a suspending liquid is prepared; the suspending liquid is then placed into an ultrasound reactor for decomposition, so that calcium hydroxide particles with nanometer-scale grain size are prepared. The preparation method has the characteristics that the raw materials are cheap and can be easily obtained, the decomposition liquid can be repeatedly used, the preparation condition is mild, the preparation process is simple and convenient, and the prepared nanometer calcium hydroxide is high in purity and uniform in particle size distribution; the preparation method can satisfy different requirements for environment management, fire-resisting materials, medicine, and other special fields.

The invention belongs to the technical field of surface protection and magnetically conductive coating, and discloses a titanium alloy surface high magnetically conductive and wear-resistant coating material used for magnetic fluid sealing, a preparation method and application thereof. The coating material sequentially includes a wear-resistant layer, a main body layer and a transition layer, and the transition layer is located between the substrate and the main body layer; the composition of the transition layer is: 85-97% of iron-cobalt-vanadium alloy, 1-5% of Si , B 1-5%; the composition of the main body layer is: iron-cobalt-vanadium alloy 85-95%, Si 2-5%, B 2-5%, WC 1-5%; the composition of the wear-resistant layer is : Iron-cobalt-vanadium alloy 70-80%, Si 1-5%, B 1-5%, WC 10-20%. The coating material has multifunctional integration of high hardness, good wear resistance and high magnetic permeability. Prepared by laser cladding, the coating material can be used as a titanium alloy part of a magnetic fluid sealing system in the aerospace field.

The invention belongs to the technical field of battery materials, and discloses a negative electrode material of a zinc-nickel battery, a preparation method and application thereof. The active material in the negative electrode material of the zinc-nickel battery of the present invention is basic zinc carbonate, and the basic zinc carbonate is prepared by reacting urea or ammonium bicarbonate with zinc salt; the invention also discloses the basic zinc carbonate in the negative material of the zinc-nickel battery Paste formulation of zinc carbonate, conductive agent, additives and binders. The test results of the soft-packed NiZn battery constructed by using the basic zinc carbonate as the negative electrode active material show that when the material is used as the negative electrode material of the battery, the overall electrochemical performance of the electrode and the battery containing the material is improved. The prepared pouch battery has good coulombic efficiency and cycle life, and the energy density of the battery is 130Wh kg ‑1 , the cycle stability is not less than 1200 times.