16 results about "Skutterudite" patented technology

The invention discloses a method for connecting a skutterudite thermoelectric material and an electrode by using a high-entropy alloy and low-expansion-coefficient particle composite barrier layer, and relates to a method for connecting the skutterudite thermoelectric material and the electrode. The method aims at solving the problems that an existing conductive connector for connecting a skutterudite thermoelectric material and an electrode through a barrier layer is large in thermal stress and prone to cracking. The method comprises the steps that composite powder of high-entropy alloy and low-expansion-coefficient particles is prepared through a mechanical mixing method; and preparing the high-entropy alloy and low-thermal-expansion-coefficient particle composite barrier layer by adopting a sintering method. And then the barrier layer, the skutterudite thermoelectric material and the electrode are connected into a conductive joint through a diffusion welding or brazing method. The materials of the low-expansion-coefficient reinforced particles comprise but are not limited to low-expansion metal particles, graphite and the like; the components of the high-entropy alloy matrix material comprise, but are not limited to, an Al-Co-Cr-Fe-Ni system, an Fe-Co-Ni-Cu system, an Hf-Nb-Ta-Ti-Zr system and the like. The skutterudite thermoelectric material and the electrode are connected through the composite barrier layer of the high-entropy alloy and the low-expansion-coefficient particles, and the obtained conductive connector has high mechanical strength, a low-resistance interface and excellent thermal stability at the same time. The method is suitable for connecting the skutterudite thermoelectric material and the electrode.

The application provides a method for preparing high-performance skutterudite compounds by carbon quantum dot composite modification. The method for preparing high-performance skutterudite compounds by carbon quantum dot composite modification can make carbon quantum dots quickly enter the mesoporous system of CoSb3-based skutterudite by adopting the method of rapidly ultrasonic oscillation of carbon dot solution to make carbon quantum dots enter CoSb3-based skutterudite, so that the carbon quantum dots are uniformly dispersed in the CoSb3-based skutterudite thermoelectric material, and the effect of uniform composite is achieved. Then, the CoSb3-based skutterudite thermoelectric material is prepared by combining SPS sintering. The method can meet the requirements of rapid and uniform composite, simplify the composite process, optimize the process, and obtain the CoSb3-based skutterudite thermoelectric composite material with good thermoelectric performance. The application breaks the traditional method for improving the thermoelectric performance of the existing CoSb3-based skutterudite thermoelectric material, such as doping, filling and composite metal nanophase.

The invention discloses a high-performance N-type skutterudite thermoelectric material barrier layer with a composite structure and a preparation method thereof, and belongs to the technical field of thermoelectric conversion. The preparation method comprises the following steps that a Mo target is installed at a radio frequency target position, a W target is installed at a direct current target position, a skutterudite wafer substrate is fixed to a substrate, and the substrate is heated and vacuumized; and the argon flow is set and introduced, bias voltage is started, radio frequency and direct current power supplies are synchronously started to pre-sputter the target material, then radio frequency sputtering of the Mo connecting layer and direct current sputtering of the W barrier layer are sequentially carried out, and the W-Mo composite barrier layer is prepared. The method is used for solving the technical problems that due to the limitation of the high melting point of refractory metal W, a compact tungsten barrier layer is difficult to prepare through a common sintering process, the diffusion capacity of barrier elements is reduced, mismatch of thermal expansion coefficients of the metal W and a skutterudite matrix is large, and the barrier layer is prone to failure in a thermal cycle service environment.

The application relates to a method for connecting a low-temperature and low-pressure fulling cobalt with a metal electrode based on nano-silver paper, and relates to the technical field of heterogeneous material connection. The application aims to solve the problems of high connection temperature of the existing fulling cobalt and metal electrode, serious interface chemical reaction, reduced connection strength of the joint, increased contact resistance and contact thermal resistance of the interface, and low conversion efficiency of a thermoelectric device. The application can effectively control the sintered silver organization structure, and then control the joint organization and performance by controlling the nano-silver paper connection temperature, holding time and sintering pressure. Compared with the commonly used brazing and diffusion welding method, the welding temperature is low, and the welding pressure is small. Compared with the nano-silver paste sintering, the sintering quality is high, and the cost is low. The application can obtain a method for connecting a low-temperature and low-pressure fulling cobalt with a metal electrode based on nano-silver paper.

A method for brazing skutterudites and copper electrodes using copper-tin-phosphorus solder relates to the technical field of brazing dissimilar materials. The purpose of the present invention is to solve the problem in the existing brazing process of skutterudites and copper electrodes that the solder reacts with the skutterudites due to the solder legs rising to the periphery of the skutterudites, thereby reducing the connection strength of the joint and the conversion efficiency of the thermoelectric device, resulting in the thermoelectric device being unusable. Method: First, the skutterudite thermoelectric material powder, the barrier layer and the copper powder are integrally hot-pressed and sintered, and then cut, ground, polished, ultrasonically cleaned and dried to obtain the skutterudite thermoelectric material to be welded; the surface to be welded of the copper electrode is ground, polished, ultrasonically cleaned and dried to obtain the copper electrode to be welded; the copper-tin-phosphorus solder is placed between the skutterudite thermoelectric material to be welded and the surface to be welded of the copper electrode to be welded, and the welding is carried out in a vacuum environment, and finally the temperature is lowered to room temperature. The present invention can obtain a method for brazing skutterudites and copper electrodes using copper-tin-phosphorus solder.

The invention relates to a method for preparing an iron-based filled skutterudite material through liquid-phase reaction sintering. The method comprises the following steps that S1, high-purity Ba sheets, In powder, Co powder, Fe powder and Sb powder are weighed according to a specific molar ratio and then mixed to be uniform; s2, putting the powder into a clean graphite crucible, and sealing the clean graphite crucible in a quartz tube under a vacuum condition; s3, the quartz tube is placed in a muffle furnace, the temperature is slowly increased to the quenching temperature, heat preservation is conducted for a certain time, then quenching is conducted in oil to obtain a cast ingot, and then the cast ingot is ground into powder and sieved; and S4, carrying out two-step plasma sintering on the sieved powder under vacuum by utilizing spark plasma sintering equipment to obtain the block iron-based filled skutterudite material. The method is low in preparation cost, short in preparation period and high in reliability, and fills the technical blank of low-cost and high-efficiency preparation of the iron-based skutterudite material at present.

The invention discloses a rapid preparation method of a CoSb3-based thermoelectric material and an induction melting and sintering device, and the preparation method comprises the steps: calculating an element ratio, weighing Cu powder, B powder, Co powder, Sb powder and Te powder obtained through calculation, mixing, and pressing into a columnar sample through a powder tablet press; putting the columnar sample into a metal cylinder mold, and then sealing the metal cylinder mold in a quartz glass tube; placing the quartz glass tube in an induction melting furnace, vacuumizing the quartz glass tube by using a vacuum pump, heating at certain induction heating power, taking out the metal cylinder mold from the quartz glass tube after heating for a period of time, quenching, taking out a sample, and grinding the prepared product to obtain a final finished product; according to the method, the skutterudite compound Cu < 0.1 > BCo < 4 > Sb < 11 >. 5 Te < 0.5 > is successfully prepared under the conditions of different heating powers and heating times by utilizing the rapid heating and electromagnetic stirring effects of electromagnetic induction smelting.

The present invention relates to the technical field of thermoelectric components, and specifically discloses a skutterudite thermoelectric component and its preparation method and application. The present invention develops two different types of anti-diffusion layer alloy compositions for N-type and P-type thermoelectric materials in thermoelectric components, respectively, so that their linear expansion coefficients match those of N-type and P-type thermoelectric materials, respectively, to reduce the thermal stress of the interface, thereby improving the reliability and service life of the thermoelectric device. Among them, the anti-diffusion layer composition for N-type thermoelectric material is Fe a Cr b V c , the composition of the anti-diffusion layer for P-type thermoelectric materials is Fe a’ Cr b’ Si c’ ; Wherein, a, b, c, a', b', c' represent the mass percentage of each component, a+b+c=100, a'+b'+c'=100; 70≤a≤90, 10≤b≤20, 0<c≤10; 70≤a'≤90, 10≤b'≤20, 0<c'≤10; a and a', b and b', c and c' may be the same or different.

The application discloses a high-thermal-stability welding method for a skutterudite thermoelectric material / electrode based on a metal ceramic composite barrier layer, and relates to a connecting method for a skutterudite-based thermoelectric material and a metal electrode. In order to solve the problem that there is a strong element diffusion between the skutterudite and the metal electrode, so that the strength and the interface resistance are increased, and the welding joint strength is low and the service life is reduced. The application uses a metal ceramic composite phase as a diffusion barrier layer, and has high connecting strength, low joint resistance and slow thickness growth of a reaction layer under long-term service, so that good mechanical properties and use performance are maintained. The application can control the composition and proportion of the overall barrier layer by selecting different refractory metals and ceramics, can control the type, thickness and distribution mode of the interface reaction layer by controlling the welding temperature and holding time, and then control the strength and thermal / electric transport performance of the welding joint.

The application relates to a method for connecting a skutterudite thermoelectric material and an electrode by using a surface-textured barrier layer, and relates to the technical field of connection of a skutterudite thermoelectric material and an electrode. The application aims to solve the problem that the existing welding method for the skutterudite thermoelectric material cannot obtain a joint with high mechanical performance and low contact resistance. The method comprises the following steps: etching a plurality of parallel grooves on the surface of the barrier layer to be welded by using a laser, integrating the skutterudite thermoelectric material and the barrier layer subjected to the texturing treatment by means of hot-pressing sintering, and making the surface of the barrier layer subjected to the texturing treatment face the skutterudite thermoelectric material; placing a filler between the skutterudite thermoelectric material and the electrode to be welded to obtain a workpiece A to be welded, and carrying out brazing on the workpiece A to be welded, or directly contacting the skutterudite thermoelectric material and the electrode to be welded to obtain a workpiece B to be welded, and carrying out diffusion welding on the workpiece B to be welded. The application can obtain a method for connecting a skutterudite thermoelectric material and an electrode by using a surface-textured barrier layer.

The invention relates to a filled skutterudite crystal and a preparation method thereof, and belongs to the technical field of skutterudite materials. The chemical formula of the crystal is TexRh4Sb12, wherein x ranges from 0.1 to 1; the crystal is a cubic system, the space group is Im-3 (NO.204), the lattice constant alpha = beta = gamma = 90 degrees, and the theoretical density of the primitive cell volume of the crystal is 8.1-8.5 g / cm < 3 >. The crystal is subjected to semiconductor-insulator conversion along with temperature reduction, has sensitivity and relatively high resistivity at low temperature, is a potential energy material, and has obvious application value in the fields of thermoelectric conversion, temperature sensing and the like.

Provided is a method for manufacturing a thermoelectric conversion element. If upsizing is performed for mass production, the pressure during pressure sintering is likely to be insufficient, and the relative density of the thermoelectric conversion element is likely to be insufficient, due to insufficient load and the like resulting from upsizing of the area of the pressure surface. As a solution, a method for manufacturing a thermoelectric conversion element is characterized by comprising: a step of mixing a powder of a skutterudite-type thermoelectric conversion material containing Sb and a sintering aid containing a compound composed of Mn and Sb to obtain a mixture; and a step of sintering the mixture.

A method for preparing a bimetallic stacked barrier layer with adjustable thermal expansion coefficient and improved stability is disclosed, relating to the field of thermoelectric device technology. The method includes the following steps: Nb and Cu metal foils are stacked alternately to form a multilayer stacked structure, and interfacial bonding is performed via diffusion bonding to obtain an Nb-Cu barrier layer; raw materials are weighed according to the atomic ratios of n-type and p-type cobaltite thermoelectric materials, and the prepared raw materials are vacuum melted to obtain n-type and p-type cobaltite ingots, respectively; the n-type and p-type cobaltite ingots are respectively subjected to melt spinning treatment to obtain corresponding n-type and p-type cobaltite powders; the obtained barrier layer and cobaltite powder are placed together in a mold, with the barrier layer located at the bottom of the mold and the n-type or p-type cobaltite powder placed on top of the barrier layer; after flattening, hot-pressing sintering is performed, followed by furnace cooling to obtain an n-type or p-type cobaltite thermoelectric material with a barrier layer on its surface.

The skutterudite thermoelectric device comprises an electrode layer, a brazing layer, a barrier layer, an adhesion layer and a skutterudite thermoelectric material layer, the electrode layer is made of a molybdenum-copper alloy material, the barrier layer is made of a tungsten material, the molybdenum-copper electrode layer and the tungsten barrier layer are in brazed connection, and the adhesion layer is made of an adhesion layer. The tungsten barrier layer and the skutterudite thermoelectric material layer are connected through an adhesion layer. According to the design scheme of the interface structure of the high-stability thermoelectric device provided by the invention, the problem of device failure caused by disconnection of the copper electrode in the service period is solved, and the performance and efficiency of the skutterudite thermoelectric device are greatly improved.

A method for improving the strength and long-term service performance of brazed joints in skutterudite thermoelectric devices using a cobalt-based barrier layer belongs to the technical field of thermoelectric material connection. In order to solve the problems of poor long-term service performance and low strength of brazed joints of the existing skutterudite and electrode, a cobalt-based barrier layer is added between the skutterudite and the electrode, which is cobalt and refractory metal. The refractory metal has high melting point, large bond energy and high diffusion activation energy, thereby inhibiting the diffusion of Sb element through the barrier layer to the electrode. Therefore, the composition of the cobalt-based barrier layer can be flexibly adjusted so that the thermal expansion coefficient of the barrier layer is easily matched with that of the skutterudite. Moreover, the barrier layer powder and the skutterudite powder are integrated by hot-pressing sintering, and a staggered interface is formed between the powder and the powder, which can well relieve the interface stress. The barrier layer of the present application can better inhibit the diffusion of Sb element because it contains fewer grain boundaries. The shear strength of the brazed joint of the skutterudite and the electrode obtained by the present application reaches 33.6 MPa.

The invention discloses a low-temperature solid-phase reaction preparation method of a skutterudite type thermoelectric material based on a magnetic field condition, and the method comprises the steps: calculating the element ratio of a Cu0. 1BCo4Sb11. 5Te0. 5 skutterudite compound, transferring Cu powder, Co powder, Sb powder, Te powder and B powder which are weighed according to the ratio into a ball milling tank to form a mixture, carrying out the vacuum pumping, carrying out the ball milling for 2 hours, and then taking out the mixture to prepare a grinding system; putting the grinding system into a tablet press for cold pressing to obtain tablets; putting the sheet-shaped object into a prepared sintering mold, carrying out vacuum atmosphere low-temperature sintering in a 0.5 T magnetic field environment, cooling to room temperature after sintering is finished, and taking out the sheet-shaped object; under the condition of a magnetic field, according to the trend that the absolute value of the Seebeck coefficient of the skutterudite type thermoelectric material prepared through a low-temperature solid-phase reaction is increased and the overall resistivity is reduced, the power factor is obviously increased, and under the magnetic field, a synthesized sample has small-size crystal grains, rich crystal boundaries and the characteristics of a small number of pores.