34results about How to "Improve thermomechanical properties" patented technology

The invention relates to a spherical nano-silica material with dual particle size distribution and a preparation method thereof. The preparation method of the spherical nano-silica material with dual particle size distribution comprises the following steps: preparing an alcoholic solution containing a silicon precursor; preparing an alcoholic solution containing water and a catalyst; and mixing the alcoholic solution containing the silicon precursor and the alcoholic solution containing water and the catalyst to obtain a mixture, stirring the mixture to react for 4-10 hours at 25-60 DEG C, and separating and purifying to obtain the spherical nano-silica material with dual particle size distribution. Experiments prove that the preparation method of the spherical nano-silica material with dual particle size distribution can be used for preparing the spherical nano-silica material with dual particle size distribution in situ. The preparation method disclosed by the invention is simple in process and capable of preparing the spherical nano-silica material with dual particle size distribution in a large scale, so that the thermomechanical performance of an electronically-packaged composite is improved.

The invention relates to a double-ring silicon through silicon via structure and a manufacturing method thereof. The double-ring silicon through silicon via structure comprises a semiconductor substrate, a first dielectric layer, a first metal ring, a second dielectric layer, a second metal ring and a dielectric core layer sequentially from outside to inside. The manufacturing method of the double-ring silicon through silicon via structure includes: (1) forming a through via in the semiconductor substrate by etching; (2) preparing the first dielectric layer on the inner surface of the through via; (3) preparing the first metal ring on the surface of the first dielectric layer; (4) preparing the second dielectric layer on the surface of the first metal ring; (5) preparing the second metal ring on the surface of the second dielectric layer; (6) preparing the dielectric core layer on the surface of the second metal ring until fullness is achieved; (7) performing chemical mechanical polishing on the upper surfaces of the semiconductor substrate and the through silicon via. By adoption of the first metal ring which is arranged outside and grounded, a function of shielding noise signals is realized, and high integrity of high-frequency signals is achieved; by adoption of the second metal ring arranged inside, thermal stress is reduced, and thermo-mechanical property is improved.

The invention discloses a flame-proof polyacrylonitrile fiber and its manufacturing method. Said fiber comprises at least 5%-25% by polyacrylonitrile weight of APP flame retardant, or APP flame retardant treated by silane coupler or titanate coupler, furthmore, comprises pentaerythritol, bi-pentaerythritol and like polyhydric alcohol compound, which has a APP-to-polyhydric alcohol ratio ranging from 2 to 3.8 by wt / wt. The method for manufacturing said fiber includes: crossblending the flame retardant with the inorganic solvent spinning dope of polyacrylonitrile, which is obtained by one-step method or two-step method to prepare crossblending spinning dope, then spinning, washing, drafting and thermal sizing by using current technique of making acrylon with inorganic solvent spinning line. The invention applies cheap, non-poisonous and high efficient inorganic additive flame retardant APP to spin flame retardant acrylon, as a result, crossblending spinning dope with good spinnability and fiber with high flame retardancy is obtained.

The invention discloses a method for improving the medium-temperature mechanical property of Mg-Al series magnesium alloy pressure castings. The method comprises the steps of die-cast formation of magnesium alloy subjected to smelting and aging treatment of the pressure castings subjected to die-cast formation and is characterized in that the aging treatment is directly carried out on the pressure castings after die-cast formation; Pb and Sn are added in the smelting process of the magnesium alloy. The method has the advantages that the Pb and the Sn have the grain refinement effect on structures of the Mg-Al series magnesium alloy pressure castings, the Pb can reduce precipitation of harmful discontinuous second-phase Mg17Al12 and enhance precipitation of beneficial continuous second-phase Mg17Al12 after the aging treatment, and the Sn can form high-melting-point Mg2Sn particles for being precipitated with Mg in the aging process. According to the method, the aging heat treatment is directly carried out instead of being carried out after solution treatment, and therefore the problem that bubbles are generated on the surfaces of the magnesium alloy pressure castings because the temperature is excessively high in the solution treatment process can be avoided.

The invention belongs to the field of electrical and signal connection technologies, and particularly relates to an electrical connector. The electrical connector comprises an inner conductor, an installation board and a shell body, and is characterized in that: the inner conductor is made of copper alloy, and is composed of the following components by weight: 0.012 to 0.043% of cobalt, 0.034 to 0.045% of vanadium, 0.038 to 0.045% of manganese, 0.078 to 0.088% of zinc, 0.12 to 0.20% of silicon, 0.020 to 0.032% of samarium, 0.032 to 0.042% of titanium, 0.022 to 0.034% of tin, 0.045 to 0.056% of nickel, and the balance being copper. The inner conductor adopted by the electrical connector has excellent conductive performance and high strength, the tensile strength thereof reaches 610 to 635Mpa, the conductivity ranges from 81 to 83.5% IACS, and the softening-resistant temperature reaches 455 to 468 DEG C.

The invention relates to the preparation, product and application of a polyester / periodic mesoporous bone filling composite material whose degradation rate can be fluorescently marked. Firstly, rare earth periodic mesoporous nanoparticles with fluorescent properties were synthesized, then the rare earth periodic mesoporous nanoparticles were chemically modified with low molecular weight poly-L-lactic acid as a modifier, and finally added to the polyester matrix by solution blending middle. The product obtained by the above method and the application of the product as a composite bone filling material in bone repair are also provided. The fluorescent mesoporous material obtained by the method of the invention is evenly dispersed in the organic matrix, the mechanical properties of the polyester base are greatly improved, and the degradation behavior of the composite bone filling material can be monitored in real time. The preparation process is simple, and it can be used as a bone filling material for load-bearing bone parts with high performance index requirements. The obtained composite material can meet the requirement of clinical application.

The invention provides a preparation method of a zirconia ceramic ferrule and a preparation method of a zirconia powder base material used for the zirconia ceramic ferrule. The titanium dioxide used in the present invention makes the material have excellent fluidity in the injection molding process, and the synergistic effect of magnesium oxide, zinc oxide and titanium oxide obtains better linear expansion coefficient and thermal stress performance than pure zirconia ceramics, and improves the entire system at the same time Excellent thermomechanical properties make the material have high strength. Second, ethylene-vinyl acetate copolymer has high elasticity and toughness. Polyurethane elastomer, polyacetal resin, high-melt strength polypropylene, etc. are interspersed in zirconia powder through ethylene-vinyl acetate copolymer to polymerize these organic The adhesive forms a structure that intersects the network very well, and a stable structural system is obtained, so that the formed ceramic ferrule is not easily deformed. Third, the polyaldehyde resin is used as an organic binder to make the molded body have high strength, good shape retention, fast degreasing speed and high precision.