85results about How to "Controllable porosity" patented technology

Porous bioabsorbable, bioactive and load-bearing composite medical device structure includes a plurality of regular textile planar layers (1a, 1b . . . ) formed of continuous bioabsorbable polymer matrix and bioceramic fibers acting as reinforcements, both included in continuous fibrous elements (3) forming the textile layers. The layers are placed on top of each other to form a structure having two dimensions (x, y) at right angles to each other according to the two dimensions of the textile layer and a third dimension (z) perpendicular to them and resulting from the piling of the layers. A plurality of passages extend through the layers as a result of the openings (2) defined by portions of the continuous fibrous elements (3) extending substantially in the direction of the plane. The continuous fibrous elements (3) comprise both bioactive ceramic reinforcing fibers which form a reinforcing structure and a bioabsorbable polymer matrix material which forms a matrix which binds the layers together and also binds the portions of continuous fibers defining the openings together, thereby forming the passages and stiffening the structure. This bioactive and bioabsorbable composite structure is suitable to be used as a basic structure in medical devices, especially in osteochondral applications where the load-bearing properties of implant are required.

The invention relates to a solid oxide fuel cell and a preparation method thereof. The cell is formed by sequentially depositing a porous anode functional layer, a dense electrolyte layer and a porous cathode functional layer on a porous anode supporting body with perovskite type oxide serving as an anode material, a porous cathode layer is deposited on the reduced porous cathode functional layer, nanometer-doped cerium oxide is deposited in the porous perovskite anode supporting body and the porous anode functional layer, and nanometer-doped cerium oxide and a nanometer cathode material are sequentially deposited in the porous cathode functional layer. The prepared solid oxide fuel cell is stable in structure for a long time and can endure oxidization-reduction circulation multiple times, carbon deposition is resisted, and the sulfur-resistant performance is achieved.

The invention discloses a preparation method for a porous tungsten bulk material with uniform and controllable pores. The preparation method is characterized by comprising the following steps of: by taking tungsten powder as a raw material, obtaining spherical tungsten powder through plasma balling treatment and electric vibrating and screening treatment; and then, obtaining the porous tungsten bulk material by discharge plasma sintering. According to the preparation method, the porous tungsten bulk material with uniform and controllable pores is obtained by combining a plasma balling technology, an electric vibrating and screening technology and a discharge plasma sintering technology; the preparation method is simple and liable to realize; the control on pores of the product can be realized by regulating the process parameters, so that the porous tungsten bulk material with porosity of 17%-22.5% and pore size of 2-5 mum; the prepared porous tungsten bulk material can be used for remarkably improving the infiltration performance of the material, so that the launch stability of a barium-tungsten cathode is greatly improved, and the service life of the barium-tungsten cathode is prolonged.

The invention discloses a preparation method of a pore-controllable porous nickel-titanium shape memory alloy, and the preparation method comprises the following steps: uniformly mixing an additive solution and nickel-titanium alloy powder to obtain nickel-titanium alloy slurry; filling a porous template with the nickel-titanium alloy slurry to obtain a porous template containing nickel-titanium alloy slurry; performing vacuum drying on the porous template containing nickel-titanium alloy slurry to obtain a biscuit; in a protective gas atmosphere, heating the biscuit to 400-500 DEG C and performing degreasing treatment to obtain degreased biscuit; in a vacuum condition, sintering the degreased biscuit at 1,000-1,200 DEG C for 120-240 minutes so as to obtain the pore-controllable porous nickel-titanium shape memory alloy. In the preparation method, the preparation process is simple, the equipment is simple, the cost is low, the pore performance of the porous nickel-titanium shape memory alloy can be adjusted, and the prepared pore-controllable porous nickel-titanium shape memory alloy has high porosity and uniform pores and a three-dimensional communication structure.

The invention discloses a low-temperature dynamic constraint loading-sintering method for preparing metal porous materials. A preparation process is as follows: to-be-sintered metal blank or powder is directly put into a sintering mold; a heat-resistant loading weight with a limiting stopper is placed on the to-be-sintered metal blank or powder; the gravity of the loading weight is utilized to apply pressure to the to-be-sintered metal blank or powder; then the sintering mold is placed in a vacuum sintering furnace; and low-temperature dynamic constraint loading-sintering is performed under the condition lower than a common metal porous material sintering temperature, so as to prepare the metal porous materials. The low-temperature dynamic constraint loading-sintering method adopted by the invention comprises the following steps of adopting a loading mold with simple structure in a common powder-metallurgy vacuum sintering furnace, utilizing the deadweight phenomenon of the mold to mutually bond metal particles thermally softened and finishing sintering the metal porous materials at a low temperature, which avoids the phenomenon that metal high-temperature grains grow up. The metal porous materials are adjustable in size and controllable in porosity. The method has the advantage of greatly reducing production cost, along with simple process.

The invention discloses a slurry direct writing forming method of a diamond tool, which comprises the following steps: (1) fully mixing nano ceramic powder, PMMA (polymethyl methacrylate) and diamond microparticles to obtain mixed powder; (2) fully dispersing xanthan gum in deionized water to obtain a xanthan gum solution; (3) uniformly mixing the mixed powder prepared in the step (1) with the xanthan gum solution obtained in the step (2) to obtain slurry; (4) adding the slurry prepared in the step (3) into a needle cylinder of slurry direct writing forming equipment, and printing into a designed shape in a layer-by-layer overlapping manner to obtain a green body; and (5) drying the green body prepared in the step (4) to constant weight, and then sintering to obtain the diamond tool. The diamond tool with a complex structure can be manufactured at a time through slurry direct writing forming, and the diamond tool has high consistency, proper mechanical property, controllable porosity and high shape precision.

The invention discloses a method for preparing porous ceramic by coating beta-Si3N4 particles with a composite oxide CaO-SiO2-B2O3, which is a porous body preparation technology comprising the following steps: the beta-Si3N4 particles are put into a CaO-SiO2-B2O3 sol made from tetraethoxysilane, boric acid, calcium nitrate, citric acid, absolute ethyl alcohol and deionized water, and the vacuum filtration method is adopted to form the porous body by self porous structure of the columnar beta-Si3N4 crystalline particles. The surface of the sintered beta-Si3N4 particles is coated with a modification layer of CaO-SiO2-B2O3 oxide interface, and the modification layer effectively connects the beta-Si3N4 particles and prevents the beta-Si3N4 particles from oxidation at high temperature. The porous ceramic prepared by the method can be used as a radome and a catalyst carrier material.

The invention relates to a low-VOC lubricating agent doped with self-assembly core-shell inorganic particles and used for polyolefin and a preparation method of the low-VOC lubricating agent and belongs to the field of production and processing of novel high polymer materials. The preparation method aims to solve the problems that high-shear friction occurs and volatile pollutants are easily decomposed due to high-temperature heating during the high-temperature forming process of the lubricating agent for the polyolefin and is characterized in that the electrostatic layer-by-layer self-assembly technique is used to prepare the core-shell inorganic particles with high adsorption performance, shell layer thickness and shell layer particle pores can be controlled, and the core-shell inorganic particles are compounded with other auxiliaries to prepare the low-VOC efficient lubricating agent. The lubricating agent prepared by the method has the advantages that the lubricating agent can greatly improve processing rheological properties and lubricating properties during the high-temperature forming of polymer polyolefin materials, and VOC content can be lowered to below 120 microgram C / g.

The invention discloses a porous titanium-aluminum-based alloy material, a preparation method and application thereof. According to the porous titanium-aluminum-based alloy material, titanium powder and aluminum powder are adopted as raw materials, and the porous titanium-aluminum-based alloy material is prepared and acquired by adopting a metal powder injection molding technology. No pore formingagent is added in the preparation process of the porous material; instead, difference of the diffusion coefficient between aluminum and titanium is utilized; and aluminum diffuses in titanium, and ahigh-porosity material is acquired. The porous titanium-aluminum-based alloy material prepared by adopting the method is molded in a near-net manner; the interior of pores is clean and environment-protective; and the material can be applied to fields such as medical implantation and the like as an implanted material.