33results about How to "Avoid mechanical performance degradation" patented technology

The invention discloses a microcellular foaming injection molding technology capable of realizing the high foaming ratio and preventing a surface from having foam marks. The technology comprises steps as follows: polymer melt and a foaming agent are mixed, a preformed blank is molded and transferred, heating and foaming are performed, and a final product is obtained after cooling. The preformed blank and the final product are molded in two mold cavities with different volumes. High cavity pressure, high injection pressure and high holding pressure are adopted, so that the preformed blank is prevented from foaming in the molding process. After the cooled preformed blank is fixed in a final product molding cavity, molds are closed and heated, and the inside of the preformed blank foams. Through the high-pressure injection technology of the preformed blank, the surface of the product can be free of defects such as crazing, spiral stripes, foam pits and the like, and the volume difference between the preformed blank and the final product provides space for growth of a bubble-shaped nucleus. The technology can be used for producing microcellular foaming injection molded products with good surface quality and dense inside cells.

The invention discloses a synthesis method of wholly aromatic polyamide. The synthesis method of the wholly aromatic polyamide comprises the following steps: (1) synthesizing a polymeric monomer 5-cis-butene imidodicarbonic diamide terephthalic acid; and (2) completely dissolving a chaotropic agent with the mass fraction of 0.5-6.0% in an organic solvent, adding 5-cis-butene imidodicarbonic diamide isophthalic acid synthesized in the step (1) and aromatic diamine in an equal molar ratio, cooling, precipitating, washing and drying, thus obtaining the wholly aromatic polyamide product. The synthesis method of the wholly aromatic polyamide has the advantages that the wholly aromatic polyamide synthesized through homopolymerization can be used for effectively improving solubility of a polymer in an organic solvent, so that the aromatic polyamide can be conveniently dissolved into the organic solvent for carrying out a spinning processing technique and the like; meanwhile, the prepared wholly aromatic polyamide is regular in a molecular chain and high in rigidity, so that mechanical properties can be not reduced, and the application field of the wholly aromatic polyamide is expanded.

The invention provides an atomization adding device and an atomization adding method for a neodymium iron boron magnetic powder mixing additive. Specifically, the atomization adding device for the neodymium iron boron magnetic powder mixing additive comprises a storage barrel, a weighing barrel, a control system, a connecting rod, a blocking piece and a powder container, wherein the storage barreland the weighing barrel are in flexible connection, the weighing barrel is connected with the control system through a weighing sensor, the weighing barrel and the powder container are connected through the connecting rod, and the blocking piece is arranged at an opening of the powder container, and the connecting rod penetrates through the blocking piece to extend into the powder container. Whenthe atomization adding device for the neodymium iron boron magnetic powder mixing additive is used for adding, the adding device is not in direct contact with the powder, and the air replacement process of the connecting part is introduced, so that oxidation caused by contact of oxygen and the powder in the additive adding process of neodymium iron boron powder and caking and blocking of the powder at an adding opening can be effectively avoided; and therefore, the use, cleaning and maintenance are simple; And meanwhile, atomized additive liquid drops are directly sprayed to the powder duringaddition and cannot be sprayed to the inner wall of the container to cause caking of the powder on the wall of the tank, so that the accuracy of the additive addition amount and the mixing uniformityare improved.

The invention relates to a preparation method for improving the mechanical property of a giant magnetostrictive material, and belongs to the field of magnetic materials. The preparation method concretely comprises the following steps of preparing a giant magnetostrictive material terbium-dysprosium-iron alloy with specific orientation through blending, vacuum smelting and directional solidification; placing a sample to be treated into a heat treating furnace, vacuumizing to 0.01 Pa, and then starting heating; continuously vacuumizing in a temperature increasing process; after the temperature inside the heat treating furnace is increased to 800-1200 DEG C, stopping vacuumization; introducing high-purity argon to increase the pressure inside the heat treating furnace to 1-20 MPa, and preserving the heat for 30-180 minutes; after heat preservation is finished, stopping heating, and after the sample is cooled, taking out. According to the invention, the growth of an RFe2 phase contained in the terbium-dysprosium-iron alloy can be inhibited through high-pressure heat treatment; the holes and microcracks can be decreased by regulating the diffusion and separation of a rare earth-rich phase; the coalescence of the microcracks of the material is promoted, so that the mechanical property of the giant magnetostrictive material can be improved, the waste, which is caused due to poor mechanical property, of the material is reduced, and the requirement for usage under the condition of more working conditions is met. The preparation method disclosed by the invention is easy to operate and suitable for industrialized production.

The invention discloses a method for preparing a high-temperature-resistant reinforced and toughened Ox / Ox composite material, and relates to the technical field of ceramic-based composite materials. The present invention first adopts the mixed solution of ammonium dichromate and anhydrous oxalic acid to pre-treat the alumina fiber fabric by impregnation-heat treatment to obtain the surface-coated alumina fiber, and then put it into CVI to prepare pyrolytic carbon coating or BN coating. The nanowire coating is obtained by electrophoretic deposition on the coating, and then the alumina ceramic slurry is coated on the surface of the alumina fiber fabric with the nanowire coating for hot pressing and sintering to obtain a high-performance Ox / Ox composites. The invention provides a method for preparing a high-temperature-resistant reinforced and toughened Ox / Ox composite material, which obtains a high-density matrix and a porous nano-oxide coating, so that a weak interface is formed between the alumina fiber and the alumina matrix, thereby obtaining A high-strength, high-toughness, high-temperature-resistant alumina fiber-reinforced alumina matrix composite was developed.

The invention discloses a method for synthesizing a wholly aromatic polyamide, which comprises the following contents: (1) synthesizing a polymerization monomer 5-maleimide terephthalic acid; (2) converting the mass fraction to 0.5~ 6.0% of the solubilizer is completely dissolved in the organic solvent, and the 5-maleimide-based isophthalic acid and aromatic diamine synthesized in equimolar ratio step (1) are added for homopolymerization reaction, after cooling , precipitation, washing and drying to obtain a fully aromatic polyamide product. The fully aromatic polyamide synthesized by homopolymerization in the present invention can effectively improve the solubility of the polymer in organic solvents, which is beneficial to dissolving aromatic polyamide in organic solvents for spinning and other processing techniques, and the fully aromatic polyamide prepared at the same time The molecular chain of aromatic polyamide is regular and rigid, which avoids the decline of mechanical properties and expands the application field of fully aromatic polyamide.

The invention discloses a microcellular foam injection molding process with high foaming magnification and no bubble marks on the surface, including: mixing of polymer melt and foaming agent, preform forming, preform transfer, heating foaming, and obtaining after coolingFinal product.Among them, the preform and the final product are formed in two different volume mold cavities.High cavity pressure, high injection pressure and high holding pressure are used to prevent foaming during preform molding. After the cooled preform is fixed in the forming cavity of the final product, the mold is closed and the mold is heated to foam the interior of the preform.The high-pressure injection process of the preforms can avoid defects such as silver lines, spiral lines, and blisters on the surface of the product, and the volume difference between the preforms and the final product provides space for bubble nucleus growth. The process can be used to produce microcellular foamed injection molded parts with good surface quality and dense internal cells.

A method for improving the mechanical properties of a carbon fiber reinforced aluminum matrix composite material relates to a method for improving the mechanical properties of a carbon fiber reinforced aluminum matrix composite material. The purpose is to solve the problem that the interface between aluminum alloy and carbon fiber is easy to generate interface product Al during the preparation of existing carbon fiber reinforced aluminum matrix composites. 4 C 3 The problem. Method: take aluminum cerium master alloy and aluminum alloy as raw materials, heat and melt aluminum alloy at high temperature, then add aluminum cerium master alloy and stir to obtain aluminum alloy melt containing cerium; carry out pressure impregnation and heat treatment. The present invention utilizes the principle of thermodynamics to segregate and precipitate on the grain boundary by adding easily segregated elements, thereby improving the interface contact state between the carbon fiber and the aluminum matrix, reducing the surface energy of the grain boundary, and reducing the interface reaction, thereby inhibiting the carbon fiber and the aluminum matrix. Interfacial reaction, reduce the damage of carbon fiber, and improve the mechanical properties of composite materials. The invention is suitable for preparing carbon fiber reinforced aluminum matrix composite materials.

The invention discloses a novel anti-corrosion coating and a preparation method of the coating, which solves the problem that the existing fly ash anti-corrosion coating is difficult to disperse and the mechanical properties of the coating are reduced. The present invention uses the reflux method to graft phenylphosphonic acid and surfactant on the surface of fly ash, so that the phenylphosphonic acid and surfactant are hydrolyzed in the heating process, and then connect with some hydroxyl groups on the surface of fly ash, grafting The final fly ash eventually becomes sea urchin-like particles. Among them, the presence of phenylphosphonic acid improves the dispersion of fly ash particles in the resin and the bonding area with the resin, thereby greatly increasing the wear resistance of the coating; at the same time, the presence of phenylphosphonic acid and surfactants The corrosion inhibitor can be more evenly dispersed into the nano-micropores of the fly ash, and its corrosion inhibition effect can be exerted, and the anti-corrosion performance of the coating can be enhanced at the same time.

The invention provides a steel bar with high weather resistance, low cost and seawater corrosion resistance and a production process. The steel bar comprises the following elementary compositions of,by weight, 0.04%-0.10% of C, 0.10%-0.50% of Si, 0.5%-1.6% of Mn, 0.03% or less of P, 0.02% or less of S, 2%-4% of Cr, 0.3%-0.5% of Cu, 0.2%-0.6% of Ni, and the balance Fe and inevitable impurities. According to the steel bar, the mechanical property meets the requirement of the steel bar for corrosion resistance, the aging strain is low, and the corrosion rate is lower than 70% that of common steel bars. The technical path of the process comprises a 70-ton ultrahigh-power electric furnace, LF ladle refining, deoxidation and alloying after steel discharging, argon blowing, continuous casting of165 square billets at four streams by four machines, a heat accumulating type stepping heating furnace, 18 non-twist tandem mills, controlled-rolling and controlled-cold cooling, finishing, packagingand storage.

The invention relates to a segmentally rolling method for a large-scale high-temperature alloy high-cylindrical forging piece. The segmentally rolling method for the large-scale high-temperature alloyhigh-cylindrical forging piece comprises the steps of after heating, forging, chambering a blank and pulling a central spindle, firstly adopting a segmental irregular mold for segmentally and locallyrolling the annular blank, and then adopting a direct-wall mold for integrally rolling the segmentally and locally rolled annular piece, wherein the segmental irregular mold comprises an irregular main roller and an irregular core roller, the roller surfaces of the irregular main roller and the irregular core roller locally contact a wall surface of the annular blank, the direct-wall mold comprises a direct-wall main roller and a direct-wall core roller, the roller surfaces of the direct-wall main roller and the direct-wall core roller partially contact the blank during the rolling process and integrally contact the blank after rolling; and coating a heat-insulation coating on the roller part of the segmentally rolled annular piece, so that the integral mechanical property of the annularpiece during a follow-up rolling process is ensured. Through the method, the utilization ratio of the material and the mechanical property and the quality of the material can be improved, and meanwhile, the requirement for the rolling force of the equipment is lowered.

The invention discloses a drop-resistant and deformation-resistant paper packaging box and a preparation process thereof. The packaging box is made of an outer layer, an outer sponge, an intermediate layer, an inner sponge and an inner layer by thermocompression bonding, and the outer layer and the inner layer are impregnated with carbon fiber and kraft paper with surface active groups increased after surface grafted polyurethane treatment, Synthesized by hot pressing, the outer sponge and the inner sponge are high-concentration polyurethane sponges, which have good energy absorption and recovery capabilities, and the middle layer is made of high-density polyethylene, compatibilizer, thermoplastic polyurethane, and light calcium carbonate. . The invention has the ability of anti-tension, anti-drop and anti-deformation, and can more effectively protect the box body and the articles in the box body.

The invention discloses a bentonite based composite sealing rod, and belongs to the technical field of building materials. The developed bentonite based composite sealing rod comprises modified bentonite, a water absorbent resin, poly-allylamine, a rubber compound, a tackifying resin, a plasticizer and an antiager. In the preparation process, the rubber is plasticated firstly to obtain a plasticated rubber, then the plasticated rubber, the modified bentonite, the water absorbent resin, the plasticizer, the antiager, the tackifying resin and the poly-allylamine are mixed, extracted and formed to obtain the bentonite based composite sealing rod, wherein the modified bentonite is prepared by mixing and ball-milling the bentonite, isocyanate and a coupling agent.

The invention relates to a preparation method for improving the mechanical property of a giant magnetostrictive material, and belongs to the field of magnetic materials. The preparation method concretely comprises the following steps of preparing a giant magnetostrictive material terbium-dysprosium-iron alloy with specific orientation through blending, vacuum smelting and directional solidification; placing a sample to be treated into a heat treating furnace, vacuumizing to 0.01 Pa, and then starting heating; continuously vacuumizing in a temperature increasing process; after the temperature inside the heat treating furnace is increased to 800-1200 DEG C, stopping vacuumization; introducing high-purity argon to increase the pressure inside the heat treating furnace to 1-20 MPa, and preserving the heat for 30-180 minutes; after heat preservation is finished, stopping heating, and after the sample is cooled, taking out. According to the invention, the growth of an RFe2 phase contained in the terbium-dysprosium-iron alloy can be inhibited through high-pressure heat treatment; the holes and microcracks can be decreased by regulating the diffusion and separation of a rare earth-rich phase; the coalescence of the microcracks of the material is promoted, so that the mechanical property of the giant magnetostrictive material can be improved, the waste, which is caused due to poor mechanical property, of the material is reduced, and the requirement for usage under the condition of more working conditions is met. The preparation method disclosed by the invention is easy to operate and suitable for industrialized production.

The invention discloses a laminated mold and a process method for microcellular foaming injection molding. The laminated mold includes at least two cavities with different volumes, the smaller one is the preform molding cavity, and the larger one is the final product molding cavity; the template participating in the preform molding is provided with gas for controlling the cavity pressure In and out of the pipeline, heating / cooling components for controlling the temperature of the mold are set in the template that participates in the molding cavity of the final product. In the present invention, a preform containing a foaming agent but without a cell structure is first molded, and then the preform is transferred into a molding cavity of a final product, and the preform is foamed and expanded by heating the mold until the entire cavity is filled. The laminated mold and its technology involved in the invention can obtain plastic parts with no bubble marks on the surface, dense inner bubbles and high expansion ratio without prolonging the injection molding production cycle.

The invention belongs to the field of aluminum alloy materials and discloses a high-strength weldable aluminum alloy. The high-strength weldable aluminum alloy includes the following components: 0.4-1.2% Mg, 0.7-1.4% Si, 0.2-0.7% Mn, 0.05-0.2% %Cu, 0.1‑0.5% Zn, 0.4‑0.6% Fe, 0.05‑0.15% Cr, 0.1‑0.3% other alloying elements, the balance is Al; other alloying elements include Ni, V, Ti, Zr, rare earth elements Combination, the ratio is 1.2-1.4: 0.6-0.8: 2.4-2.6: 0.4-0.6: 0.2; the rare earth elements include: Ce, La, Er, wherein Ce accounts for more than 60% of the total amount of rare earth elements. The aluminum alloy of the present invention improves the strength and mechanical properties through the improvement of the original formula, and can be used as aluminum alloy parts in the power battery of new energy vehicles, such as end plates, trays and the like.