115results about How to "Adjust mechanical properties" patented technology

A lead-free alloy solder containing rare-earth elements and multiple other elements for electronic package contains Ag (0.1-5 wt.%), Cu (0.1-1 wt.%), Bi (0.1-8 wt.%), In (0.1-7.5 wt.%), Sb (0-8 wt.%), the mixture of La and Ce or the mixture of La, Ce and one or both of Pr and Nd (0.01-2 wt.%) and Sn (the balance). It has liquidus temp less than 210 deg.c (even 190 deg.C or lower), less than 15 deg.c for liquidus and solidus temp difference, at least 60 MPa of yield strength, at least 18% of elongation percentage, excellent wetting ability, and high soldering quality.

The invention discloses a soluble coaxial-cone multi-layer microneedle. The microneedle is in a cone shape; an internal structure of the microneedle comprises a cone-shaped or conical-cylinder-shaped center layer, and one or more outer layers wrapping the center layer; the center layer and the outer layers are prepared by active drugs and/or structural materials; and a mass ratio of the active drugs to the structural materials is (10:1)-(1:100). The multi-layer structure of the microneedle can be dissolved layer by layer and step by step during intracutaneous contact and body fluid contact, so that the drug release time of one or more drugs and a procedure of drug release dosage can be controlled, and the microneedle can be used for partial skin treatment or whole body administration.

The invention relates to a low-viscosity dimer acid type polyamine hot melt adhesive and a preparation method thereof. The hot melt adhesive consists of the following raw materials in percentage by mole: 55 to 95 percent of dimer acid, 5 to 45 percent of aliphatic dibasic acid, 60 to 95 percent of aliphatic diamine, 5 to 40 percent of polyoxypropylene polyamine, 0.1 to 5 percent of molecular weight regulator, and the balance of water and antioxidant, wherein the dosage of the water accounts for 1 to 30 percent of the total mass of the acide and the amine; and the dosage of the antioxidant accounts for 0.1 to 2 percent of total mass of the acid and the amine. The preparation method comprises the following steps: salifying in the protection of nitrogen by using the dimer acid, the aliphatic dibasic acid and the diamine, the antioxidant and the molecular weight regulator as raw materials and introducing proper water at early stage; and heating and polycondensating. The polyamine hot melt adhesive has high and low temperature resistance, low high-temperature viscosity and simple molding process, and is mainly applied in automobile and electronic industries.

The present invention relates to a reactive monomer modified nano calcium carbonate/polypropylene mother material and its production method. Said mother material is formed from polypropylene base body, nano calcium carbonate filling material, reactive monomer (including maleic anhydride, acrylic acid and its esters and styrene) and universal stabilizing agent D of PP material. Its preparation method includes the steps of uniformly mixing by using high-speed mixing machine and extruding by means of twin screw extruder machine. Said invention can raise the mechanical property of nano calcium carbonate filled polypropylene material.

The invention discloses injectable self-repairing hydrogel based on polysaccharides, a preparation method and application of the hydrogel to biological tissue engineering, and belongs to the technical field of high polymer materials. The method includes the steps of modifying natural high polymer chitosan so that the defect that the chitosan can only be dissolved in acid solutions can be overcome and the dissolubility of the chitosan in water can be improved; conducting mixing reaction on the chitosan and a modified sodium hyaluronate derivative solution, delaying the reaction time or raising the temperature so that sol can be converted into gel and hydrogel can be endowed with the injection characteristic and the self-repairing characteristic. It is shown through cell co-culture experiments that the intelligent hydrogel has the advantage of high biocompatibility, degradability and the like. The injectable self-repairing hydrogel as a novel medical high polymer carrier material has potential biological and medical application value when used for the co-culture together with cells, protein, DNA, antigens and other active substances, and even the delivery, release and other aspects of medicine and other in-vitro substances.

The invention relates to a manufacture method of a vermicular cast iron steam cylinder cover. The vermicular cast iron steam cylinder cover is manufactured by the following ingredients according to the following mixture ratio: 75 percent to 85 percent of foundry returns and 15 percent to 25 percent of waste steel. External desulfurization is carried out after the melting, the melting temperature is controlled to be higher than 1500 DEG C, the weight percent of sulphur in desulfurized molten iron is 0.008 percent to 0.2 percent, and ingredients after the refining comprise 3.70 percent to 3.80 percent of carbon, 1.50 percent to 1.60 percent of silicon, at most 0.30 percent of manganese, at most 0.50 percent of phosphorus and 0.008 percent to 0.012 percent of sulphur. The molten iron can be perfectly subjected to vermicularizing treatment, the vermicularity is controlled to be in a proper range, the influence on the vermicularity caused by sulphur content fluctuation is avoided, the casting rejection caused by unqualified vermicularity is reduced, and the cost is reduced. In addition, the vermicular shape can be perfectly controlled, further, the mechanical performance of the vermicular cast iron can be regulated, and the performance requirement of the steam cylinder cover is met.

The invention discloses a making method of high strong tantalum and tantalum alloy as reinforced microscopic tissue structure, which is characterized by the following: increasing oxygen on the surface; forming hard closed thin case structure on the surface with oxygen solid or low-valent tantalum oxide; proceeding heat isostatic pressing solidifying; obtaining dense block material; disposing in the vacuum; adjusting dynamic property of material without growing under 2200 deg. c.

A production method of a Zn/Cu-Ag/Cu-Au composite coating steel band for a photoelectric material comprises the following steps: using a 08Al cold-rolled steel sheet as a raw material and carrying out cold rolling; after conventional degreasing, carrying out uncoiling, splitting and deburring; hot-dipping Zn; thermally spraying Cu-Ag; carrying out primary annealing at a pure nitrogen protective atmosphere; thermally spraying Cu-Au; carrying out secondary annealing at a pure nitrogen protective atmosphere; and air-cooling to a room temperature and coiling. The tensile strength is 250-300MPa, and the elongation percent is 42-48%. One Zn/Cu-Ag/Cu-Au composite coating is generated on the surface. After the Zn/Cu-Ag/Cu-Au composite coating steel band is placed under an indoor conventional atmospheric condition for 960 days, the gloss loss rate of the coating is not larger than 0.3%, and the surface corroded area is not larger than 0.3%. The product has excellent electricity and heat conductivity. After the Zn/Cu-Ag/Cu-Au composite coating steel band is kept at 300-350 DEG C for 960 days, the surface oxidized area is not larger than 0.2%, and the hardness variation rate is not larger than 0.2%. The product also has excellent welding and machining performance.

The invention discloses a medical degradable antibacterial composite material as well as a preparation method and application thereof. The composite material uses a porous magnesium alloy (6) having through holes as a reinforcement body, the holes (1) of the reinforcement body are filled with degradable polymer materials polycaprolactone and polylactic acid, and nano-magnesium oxide powder is uniformly dispersed in the degradable polymer materials. The preparation method of the composite material comprises the following steps: 1) preparing the porous magnesium alloy (6) reinforcement body; 2)mixing the nano-magnesium oxide powder, the polylactic acid and the polycaprolactone, performing mold pressing to obtain a polymer thin sheet (5); and 3) placing the polymer thin sheet (5) on the porous magnesium alloy (6), and performing extrusion and solidification to obtain the composite material. The composite material has good biocompatibility, safe, stable and controllable degradation, goodmechanical properties and an antibacterial function, is suitable for small orthopedic restoration products with various shapes, and can be used as a new generation of degradable materials to be used in bone trauma surgery, bone defect repair surgery, plastic surgery and other medical implantation fields.

The invention relates to a micromechanical system (1) which comprises a substrate (100), a suspension (130), a base (140) and a micromechanical sensor (150), the suspension (130) movably carrying the base (140) above the substrate (100) and the micromechanical sensor (150) being located on the base (140).

The invention discloses a lamination manufacturing method for a large-size and complex-structure metal component and relates to a part manufacturing method in order to solve the problem that large-size metal components which have complex special-shaped structures and high performance requirement are difficult to manufacture through traditional machining, overall plastic shaping and existing additive manufacturing methods. The manufacturing method includes the steps that firstly, a three-dimensional digital model of the large-size and complex-structure metal component is acquired, and is divided into a plurality of sheet layers; secondly, actually-usable metal plates corresponding to the thickness of the sheet layers divided in the first step are selected, and are machined so that formed plates consistent with the model of the sheet layers in the first step can be obtained; thirdly, the pieces of formed plates obtained through machining in the second step are stacked according to the sequence of the sheet layers corresponding to the first step; and fourthly, after all the formed plates are connected into a whole, and the required large-size and complex-structure metal component is obtained. The lamination manufacturing method is used for forming the large-size deep cavity inner hole complex structure component.

The invention discloses a glucosamine modified poly (ethylene glycol) diacrylate (PEGDA) hydrogel, a preparation method and application thereof. The glucosamine modified poly (ethylene glycol) diacrylate hydrogel contains 10-30 percent of poly (ethylene glycol) diacrylate, 1.0-10mM of acryloyl or propenyl glucosamine and 0.03-0.1 percent of initiating agent I2959. The preparation method comprises the steps of: preparing the PEGDA by using polyethyleneglycol as a basic material; preparing the acryloyl or propenyl glucosamine by using glucosamine hydrochloride as a raw material; and preparing a water solution or PBS (Poly (Butadiene-Styrene) solution by using the acryloyl or propenyl glucosamine and the initiating agent I2959 in a certain proportion, and can be cured into the hydrogel after being irradiated by ultraviolet with 365nm wavelength. The hydrogel can be used for tissue repair of clinical medicine, has simple preparation process, can realize in situ injection forming, meet the requirement on minimally invasive procedure, and has better application prospect and scientific significance.

The invention relates to an optical coating. The optical coating comprises 20-70wt% of oligomer, 20-70wt% of an active monomer diluent, 1-10wt% of a photoinitiator, 1-10wt% of an assistant and 0.1-2wt% of a molecular weight adjusting agent; and the oligomer is epoxy polyurethane (meth)acrylate, and the molecular weight adjusting agent is one or two or above of 1-dodecanethiol, tert-dodecanethiol, ethylhexyl 3-mercaptopropionate, pentaerythritol tetra(3-mercaptopropionate), isooctyl 3-mercaptopropionate and 2,4-diphenyl-4-methyl-1-pentene. A certain amount of the molecular weight adjusting agent is added to the formula of the coating in order to adjust the molecular weight and the curing degree in the coating radiation curing process, so the mechanical performances of the coating are changed, and the obtained coating is especially suitable for being used as a fiber coating and optical fiber ribbon.

The invention discloses a dental machinable diatomite full ceramic restoration material and a preparation method thereof; the method comprises: diatomite is taken as raw material and is added with nano toughening agent, thus adjusting the strength and the toughness of the diatomite full ceramic material; the diatomite full ceramic restoration material comprises the components of raw materials by mass percent: 30-35% of diatomite natural soil, 10-15% of bentonite, 5-7% of quartz, 40-55% of nano toughening agent and 5-7% of pH regulator; wherein the nano toughening agent contains nano zirconia (ZrO2), aluminum oxide (Al2O3) and titanium dioxide (TiO2) crystal whisker; and the pH regulator is sodium carbonate. The preparation technique comprises: the raw materials are processed by ball-milling according to a certain mass ratio, dry pressing to be molded under 500-700MPa and sintering under the ordinary pressure at 700-1150 DEG C, so that the dental machinable diatomite full ceramic restoration material can be obtained. Compared with the prior art, the invention has the characteristics of low cost of the preparation technique, stable quality, good repeatability as well as excellent mechanical property and aesthetic performance, so as to meet the requirements of clinical oral full ceramic restoration.

The invention belongs to the technical field of preparation of heat conduction materials, and discloses a preparation method of a heat-conducting gasket with high normal heat conductivity and high elasticity. The preparation method comprises the following steps: (1) with a graphite film or a graphene film as a filler, carrying out plasma modification to obtain a first modified graphite film or graphene film; (2) hydroxylating the first modified graphite film or graphene film, and grafting a hydrolyzed coupling agent to obtain a second modified graphite film or graphene film; (3) coating the surface of the second modified graphite film or graphene film with polyolefin, carrying out pre-curing treatment, and conducting stacking by adopting a laminating process to obtain a graphite film or graphene film/polyolefin multi-layer composite structure formed body; and (4) after hot-pressing treatment, conducting cutting along a direction vertical to the upper surface and the lower surface of the multi-layer composite structure formed body to obtain the heat-conducting gasket. The obtained heat-conducting gasket is good in heat-conducting property, and when a filler content reaches 94.3%, the heat conductivity of the gasket reaches 726.1 W/(m.K).

The invention relates to a single-phase multi-element rare earth magnesium alloy biodegradable material and a preparation method thereof. The material is prepared from, by weight percent, 0.1%-23.49% of Gd, 0.1%-25.3% of Dy, 0.1%-8.75% of Y, 0.1%-6.2% of Zn, 0.01%-0.6% of Zr and the balance Mg. The provided magnesium alloy biological material is a single-phase solid solution material, the content of a single impurity element influencing the alloy corrosion performance and the total content of the impurity elements are strictly controlled, the influences of precipitated phases and the impurity elements on the alloy corrosion performance are eliminated, and the corrosion resistance, the corrosion evenness and the mechanical property of the material are improved. By means of zone freezing, multi-stage solution treatment and extrusion cooling treatment, a multi-element alloy with a single phase is prepared, all the alloy elements in the alloy exist in the form of an elementary substance and the form of a solid solution state, metal ions can be completely formed in the degradation process to be absorbed by the human body or discharged out of the human body, the problem of difficult degradation of a metal compound is solved, and subsequent recovery and health of patients are facilitated.

The invention designs a novel multifunctional nano composite hydrogel, which has injectability, self-healing, and good mechanical strength, irritant reaction and adhesiveness. The multifunctional nanocomposite hydrogel is prepared by using a diol-containing polymer (PGMA) and a phenylboronic acid-containing polymer (PAPBA-STAT-PDMA) as precursors and adding a certain amount of poly-dopamine-coatedmodified nanoparticles (rGO @ PDA). In alkaline environment, a hydrogel network can be easily realized through the interaction of the phenylboronic acid- containing polymer and the diol- containing polymer. Compared with a pure polymer hydrogel without the poly-dopamine- coated modified nanoparticles (rGO @ PDA), the storage modulus (G') of the obtained nanocomposite hydrogel is significantly improved, and the nanocomposite hydrogel has adhesiveness.

The invention relates to a polyamide resin with low softening point and a preparation method thereof. The polyamide resin is prepared from dimeric acid, fatty group diamine, polyether polyamines, molecular weight conditioning agent and anti-oxidant. The total mol ratio of dimeric acid to fatty group diamine and polyether polyamines is 0.95-1.05; the mol ratio of fatty group diamine to polyether polyamines is 20-60: 40-80; the mol number of molecular weight conditioning agent is 0.1-5% of the total mol number of dimeric acid or fatty group diamine and polyether polyamines, the mass of anti-oxidant is 0.1-2% of the total mass of dimeric acid, fatty group diamine and polyether polyamines. The polyamide resin is prepared from dimeric acid, fatty group diamine, polyether polyamines and anti-oxidant by condensation polymerization, which has the advantages of good resistance to low temperature and lower softening point.

The invention relates to a polypropylene composition and a preparation method thereof. The polypropylene composition is prepared from the following components in parts by weight: 20 to 90 parts of polypropylene resin, 1 to 20 parts of organic extinction master batch, 1 to 40 parts of mineral filler and 0.5 to 5 parts of additive, wherein the organic extinction master batch is prepared from 10 to 40 parts of ethylene propylene diene monomer, 60 to 90 parts of high-density polyethylene, 0.1 to 0.3 part of cross-linking agent and 0.2 to 0.5 part of other auxiliary materials by crosslinking and extrusion. The polypropylene composition involved in the invention has the advantages of lower glossiness, good mechanical performance and good appearance, and is very suitable for automotive interior parts.

The invention provides a preparation method of polyurethane modified phenolic resin. The obtained polyurethane modified phenolic resin is suitable for semiconductor packaging. According to the methodprovided by the invention, an organic fluorine group and a polyurethane group are bonded in a phenolic resin compound through chemical bonds by controlling a ratio of the organic fluorine group to thepolyurethane group in the phenolic resin, thereby realizing effective dispersion of the organic fluorine group and the polyurethane group in phenolic resin, and the mechanical properties and surfaceproperties of a polyurethane modified phenolic resin material can be effectively adjusted. By applying the polyurethane modified phenolic resin as a curing agent to modification of an epoxy resin composition, the modulus of the epoxy resin composition can be greatly reduced, and meanwhile, the processability and solder resistance of the epoxy resin composition in the semiconductor packaging can beimproved. The polyurethane modified phenolic resin for semiconductor packaging provided by the invention also has necessary fluidity, filling property and flame retardancy.

The invention provides a process for preparing laminar zirconium boride superhigh-temperature ceramic by a casting-impregnation method, which is characterized by comprising the following steps: (1) preparing a zirconium boride casting sheet by a casting method: evenly stirring adhesive, plasticizer and solvent, adding zirconium boride ceramic powder to form a casting material, carrying out casting molding, drying at room temperature, and demolding to obtain the casting sheet which is 200-1000 mu m thick; (2) impregnating the casting sheet in graphite or boron nitride slurry by an impregnationmethod so as to impregnate the casting sheet; (3) slicing the casting sheet according to the size of a mold; (4) superposing the sliced casting sheets into the mold, and degreasing in vacuum; and (5)carrying out hot pressed sintering in an argon atmosphere to obtain the laminar zirconium boride superhigh-temperature ceramic of which the fracture toughness is up to 8.3 MPa.m<1/2>. The fracture mode of the laminar zirconium boride ceramic is non-brittle fracture, i.e. the laminar zirconium boride ceramic gradually fractures while having certain tolerance to cracking damage, and has favorable performance.

The invention relates to a biomass-based water type cylinder adhesive and a preparation method thereof. The preparation method comprises the following steps: carrying out olefine aldehyde condensation on levulinic acid and acrylic acid, and adding water as a solvent in the reaction process to obtain binary acid; carrying out amidation reaction on the prepared binary acid and diethylenetriamine in a solution, and carrying out reduced pressure distillation on an obtained product to remove a solvent and generated water, so as to prepare the water-based polyamide; preparing water-based epoxy resin from amino-terminated polyether grafted dimer acid epoxy resin with a a phosphazene catalyst as a reaction catalyst; and mixing a water-based polyamide aqueous solution with the water-based epoxy resin to obtain the biomass-based water-based cylinder adhesive. The biomass-based water-based cylinder adhesive prepared by the invention is uniform in film formation, high in rewettability and relatively high in shear strength. By changing the adding amount of the water-borne epoxy resin, the mechanical property of the cylinder adhesive can be adjusted.