101results about How to "Improve mechanical properties" patented technology

The invention relates to high-strength ultralow-density transparent silicon dioxide aerogel as well as a preparation method and application thereof. The method comprises the following steps: pre-hydrolyzing silicon ester and a structure enhancer monomer to obtain a silicon source precursor; carrying out sol-gel reaction on the silicon source precursor and an alkaline amino acid solution to obtainwet gel; soaking the wet gel in an alcoholic solution of a photoinitiator for ultraviolet radiation to obtain inorganic-organic dual-network structure enhanced wet gel; and carrying out solvent replacement and supercritical drying on the wet gel to obtain the high-strength ultralow-density transparent silicon dioxide aerogel. The prepared aerogel has the density of 5-70 mg/cm < 3 >, the light transmittance of 85%-91% and the compression strength of 0.8-2.6 MPa, solves the problem that high strength, ultralow density and high transparency cannot be achieved at the same time, and has huge application value in the fields of deep space exploration, high-energy physics, super-transparent heat insulation, solar heat collection systems and the like.

The invention discloses a block aerogel composite material and a preparation method thereof. The block aerogel composite material consists of reticular cellulose nano fiber skeletons and sol in a combining way, wherein the porosity of the aerogel composite material is 80-99.5 percent, the density is 0.015-0.680g/cm<3>, the BET specific surface area is 150-1200m<2>/g, the coefficient of heat conductivity is 0.015-0.045Wm<-1>k<-1> and the modulus of elasticity is 0.5-150MPa. The block aerogel composite material provided by the embodiment of the invention has the advantages that since the material consists of the reticular cellulose nano fiber skeletons and the sol in the combining way, the mechanical property of the block aerogel composite material can be obviously improved, the heat conductivity is low, the density is small and the specific surface area is large; and besides, the equipment cost can be decreased by adopting a relatively low and safe freeze-drying method to replace the traditional supercritical drying method.

The invention relates to attapulgite aerogel as well as a preparation method and application thereof. The preparation method comprises the following steps: (1) preparing a PVA aqueous solution; (2) stirring and mixing the PVA aqueous solution and attapulgite powder to obtain attapulgite turbid liquid; (3) carrying out ultrasonic treatment on the attapulgite turbid liquid; (4) carrying out directional solidification on the attapulgite turbid liquid to obtain a gel sample; and (5) carrying out vacuum drying on the frozen gel sample to obtain the attapulgite aerogel, and applying the attapulgiteaerogel to the field of heat preservation. Compared with the prior art, the attapulgite aerogel prepared by the preparation method disclosed by the invention is high in mechanical property, low in heat conductivity and good in flame retardance, and has a huge play space in the field of heat preservation.

The invention discloses a fiber composite warm-keeping flocculus and a preparation method thereof. The preparation method comprises the steps that a polymer solution and an adhesive enter a double-flow-channel spinneret plate through a liquid conveying pipeline, under the action of a high-voltage electric field, the polymer solution is ejected out of an electrostatic spinning nozzle through a first flow channel in an electrostatic spinning mode to form charged jet flow and solidified into fibers, and the adhesive is ejected out of an electrostatic spraying nozzle through a second flow channel to be atomized into glue drops; Meanwhile, the short fibers fall down from the outer side of the double-flow-channel spinning plate along the inner wall of a cover hopper under the induction of airflow and gravity, generate an electrostatic adsorption effect with the polymer jet flow under the polarization action of an electric field, and are uniformly and firmly embedded into a nanofiber skeleton to form an interactive penetrating and sleeving structure; and then, under the thermal physical action, molecular chains in the fibers are subjected to in-situ cross-linking reaction, the glue drops are fused among the fibers to generate bonding points, a multi-stage network cross-linking bonding structure is formed, and finally the fiber composite warm-keeping flocculus is obtained. The invention provides a method for preparing the composite flocculus with good thermal insulation property and excellent mechanical property in one step.

The invention discloses a wire arc additive manufacturing method of Al-Mg-Si alloy. The wire arc additive manufacturing method of Al-Mg-Si alloy comprises the following steps that firstly, cooling rolling is used for assisting in arc additive forming; secondly, milling is carried out on the side face and the top face of an additional material body; thirdly, a friction stir machining device is usedfor carrying out friction stir machining on the additional material body, meanwhile, in the friction stir machining process, a cooling rolling device is used for exerting cooling rolling on the sidewall of the additional material body; fourthly, finish milling is carried out on the upper surface of the additional material body for preparing of arc additive forming of the next step; fifthly, theabove steps are circularly and repeatedly executed until the final forming of the part is finished. Dendritic growth and grain refining in the Al-Mg-Si alloy additive forming process can be completelybroken, defects of air holes, cracks and the like can be effectively overcome, meanwhile, in the wire arc additive manufacturing and the modification process thereof, cooling is applied, the problemsof additional material body overheating and microstructure coarsening caused by overheating can be solved, and the mechanical property, particularly, plasticity and fatigue properties, of the addition material body can be greatly improved.

An apparatus and method for edge treating the cut edge of a glass sheet is provided which has an a heat source and a cooling system. The glass piece has an active area and a vacant edge portion. The heat source is positioned to direct heat to the vacant edge portion and raise the temperature of the vacant edge portion of the glass piece to between 350 C and 600 C. The cooling system maintains the temperature of the active area of the glass piece below 250 C. Additionally, the cooling system includes a heat sink assembly which is thermally coupled to the active area of the glass piece.

The invention discloses a full-biodegradable material with a controllable period. The full-biodegradable material comprises the following raw materials in parts by weight: 40-60 parts of polylactic acid, 20-30 parts of composite polylactic acid, 20-30 parts of an adipic acid-butylene terephthalate copolymer, 10-20 parts of polyhydroxybutyrate covalerate, 10-16 parts of glycidyl methacrylate, 6-8 parts of dicumyl peroxide, 6-8 parts of a nucleating agent and 5-10 parts of an antioxidant. According to the full-biodegradable material with the controllable period, a flexible aliphatic chain and a rigid aromatic group are contained in a molecular chain of the adipic acid-butylene terephthalate copolymer, composite polylactic acid is obtained in a melt blending mode, the composite polylactic acid is added into the degradable material, and further, the mechanical property of the degradable material can be effectively improved; and by controlling the usage amount of the nucleating agent, the degradation period of the degradable material can be conveniently controlled.

The invention discloses a preparation method of a refining agent for melting an aluminum alloy section doped with plant ash. The refining agent is prepared from the following materials in parts by weight of 6-8 parts of potassium chloride, 4-6 parts of wood ash coated particles, 3-5 parts of calcium fluoride, 3-5 parts of sodium nitrate, 5-8 parts of graphite powder, 8-10 parts of sodium fluorosilicate, 3-5 parts of sodium sulfate, 5-8 parts of aluminum chloride, 3-5 parts of potassium carbonate, 8-10 parts of attapulgite, 5-8 parts of NaBF4, 3-5 parts of sodium chloride, 5-8 parts of potassium sulphate, 8-10 parts of Na2TiF6, and 5-8 parts of NaF. High-quality aluminum alloy melting liquid is obtained by treatment of the refining agent. Therefore, the aluminum alloy melting liquid is used for casting production; the yield is obviously improved; especially the porosity in a cast is reduced by 1-2 degrees; effective control is carried out; an air hole is not generated at the surface of the cast; trapped oxide is obviously reduced; and oxide inclusion is at about two grades while the mechanical property of the cast is obviously improved.

The invention discloses a production method of a prepressing combination vertical reinforced concrete shield lining segment. The production method comprises the following steps of moving mold bodies to corresponding positions to carry out initial positioning; arranging mold cavities between the adjacent mold bodies; putting lining segment reinforcement cages in the mold cavities between the mold bodies; clamping the mold bodies to fit closely to form an overall mold for producing the shield lining segment; pouring concrete into the mold cavities, and mounting cover plates on the tops of the mold cavities for enclosing; pressuring concrete in the mold cavities through pressurizing devices and maintaining the constant pressure until the concrete finally solidifies and reaches the corresponding strength; relieving the pressure applied to the concrete in the mold cavities through the pressurizing devices and conducting steam curing on the concrete; and separating the mold bodies and conducting stripping on the shield lining segment after the concrete reaches up to the specified strength to form the shield lining segment. The production method has the advantages that the occupied area is small, the production efficiency is improved, the appearance quality of the shield lining segment is improved, the mechanical performance, anti-permeability and durability of the lining segment concrete are improved, and the overall stability is improved.

The invention discloses a dissimilar material brazing method of a porous intermediate layer structure brazing seam, relates to the field of welding of materials, and aims to solve the problems that great residual stress can be easily generated by a connector in the existing brazing process of the dissimilar material, the mechanical property of the connector is greatly reduced, even the connected connector is damaged. The method comprises the following steps of grinding and removing impurities on a ceramic matrix composite material and a metal material, then uniformly mixing a nanometer aluminum oxide template with a brazing filler to obtain a composite porous intermediate layer brazing filler, sequentially stacking the ceramic matrix composite material and the metal material, subsequently putting the composite porous intermediate layer brazing filler between the to-be-welded surfaces of the ceramic matrix composite material and the metal material to obtain a to-be-welded part; putting the to-be-welded part in a vacuum brazing furnace, vacuumizing, preserving heat at the high temperature, and finally cooling to the room temperature, thus completing the dissimilar material brazing process of the porous intermediate layer structure brazing seam. The method is suitable for brazing the dissimilar material of the porous intermediate layer structure brazing seam.