Method of producing composite branch of thermoelement operating in range of temperatures from room to 900 °c
FIELD: power engineering.
SUBSTANCE: invention relates to thermoelectric energy conversion and can be used during manufacturing of thermoelectric composite thermoelement branches, meant for making electric power generators with high coefficient of conversion. Proposed method of making composite thermoelement branches connection sections of low-, medium- and high-temperature thermoelectric materials includes preliminary application of metal coatings on ends of joined sections, selected from: nickel, indium, iron, molybdenum, tungsten, forming binding layer between sections, installation of all sections in series at increasing operating temperature of butt joint so, that between low and medium temperature sections, as well as between medium- and high-temperature sections binding layers are formed of layer stack Ni/In/N. Assembled mold is placed in plant of spark plasma sintering and heated to temperature of 450–460 °C. It is kept at this temperature for 5–8 minutes at pressure of 3–5 Mpa, in vacuum, until dissolution of boundary part of nickel in molten indium. Then it is cooled to room temperature and isothermal annealing is made in electric furnace with controlled temperature in atmosphere containing 97 % of argon and 3 % of hydrogen, at temperature of 420±2 °C at pressure of 0.5–1.0 MPa for 6–10 hours to produce high-temperature intermetallic compound Ni2In3. After diffusion welding process mold is gradually cooled to room temperature.
EFFECT: technical result is reliable and strong connection of sections of composite thermoelement branches.
6 cl, 2 dwg, 1 tbl
FIELD: power industry.
SUBSTANCE: invention relates to thermoelectric energy conversion. Essence of the invention: the method of fabrication of the structure used for manufacture of the thermoelectric generator includes the joint formation of at least one strip from the material of n-type and at least one strip from p-type material in one process operation and formation of connections at least between one strip from n-type material and at least one strip from p-type material by means of strips from the conducting material. The structure doesn't contain polymeric substrates.
EFFECT: effective method of creation of high-quality thermoelectric generator with high energy density.
15 cl, 2 dwg
SUBSTANCE: method includes forming a film with thickness of not more than 200 nm from semiconductor nanoparticles of SnO2 with size of not more than 50 nm. The film of SnO2 nanoparticles is then annealed at temperature of 330±20 K or 500±20 K for at least 15 min in an oxygen-containing atmosphere, followed by cooling to room temperature at a rate of at least 10 K/s.
EFFECT: broader functional capabilities of the material.
2 cl, 4 dwg
SUBSTANCE: method includes mechanical-activation processing in a planetary ball mill of solid solutions, which contain bismuth and antimony tellurides with an addition of a grinding agent and further sintering of obtained powders. Mechanical-activation processing is carried out successively in two stages: first, with centrifugal acceleration of grinding bodies in the interval from 800 to 1000 m/sec2 for 10-30 min, then with centrifugal acceleration of the grinding bodies in the interval from 20 to 100 m/sec2 for 20-40 min. As the grinding agent used are compounds of a layered structure, selected from the group: MoS2, MoSe, WS2, WSe, BN or graphite. The grinding agent is taken in an amount of 0.1-1.5 wt % of weight of the solid solution of bismuth and antimony tellurides. The obtained thermoelectric material consists of particles of the triple solid solutions of bismuth and antimony tellurides with a size from 5 nm to 100 nm, between which from 1 to 10 nm thick layers of a compound, selected from the group: MoS2, MoSe, WS2, WSe, BN or graphire, are located.
EFFECT: increase of the thermoelectric figure of merit.
2 cl, 3 dwg
SUBSTANCE: invention relates to thermoelectric generators. A thermoelectric generator (2) has multiple modules (1), each having a first end (3) and a second end (4) and which consist of an internal pipe (5) and an external pipe (6) and thermoelectric elements (7) in between. The modules (1) at their first end (3) or second end (4) are attached by their internal pipe (5) or external pipe (6) to an electrical conductor (9). The electrical conductor (9) is laminated and has a first end face (14) and a second end face (15), as well as a lateral surface (16). The first end face (14) is connected to the second end face (15) by multiple openings (17). Each opening is designed to attach one corresponding module (1). The electrical conductor (9) has electroconductive contacts (18) for electrical connection with contacts (8) of separate modules (1).
EFFECT: providing versatile or universal application in cars, including in existing types and models, providing reliable separation of fluid media and electrical contact.
8 cl, 15 dwg
SUBSTANCE: thermoelectric materials include polyaniline doped with various chemical additives. Manufacturing of a polymer material with p- and n-conductivity is carried out by means of the process of electric polymerisation from aqueous solution of aniline and hydrochloric acid with chemical additives.
EFFECT: increased efficiency of thermal energy conversion into electric one.
1 dwg, 1 tbl
SUBSTANCE: invention relates to the field of thermal electricity. The invention concept is as follows: insulating substrate (12) is equipped with the first (18) and second (20) junction areas. At the substrate (12) there is the first formed assembly of conductor or semiconductor elements (14) passing in parallel and in the first direction from the first (18) junction area up to the second (20) one. At the other side of the substrate (12) there is the second assembly of or semiconductor elements (22) insulated electrically from the first assembly and passing in the direction opposite from the first direction, from the first junction area (18) up to the second (20) one. In the junction areas (18, 20) the electrical connecting elements (24) connect the elements (14) and (22) of the first and second assemblies. Two elements (14, 22) of the same assembly are separated in preset direction at the preset average distance (d1, d2) in the junction areas (18, 20). The average size (P) of the connecting elements (24) in the preset direction is bigger than a maximum value of average distances (d1, d2) between elements of the same assembly. The distance (E) in the preset direction between edges of two connecting elements (24) is less than minimum values of average distances (d1, d2) between elements of the same assembly.
EFFECT: simplifying the construction and improving reliability.
6 cl, 6 dwg
SUBSTANCE: as a material for a thermoelement used is a polymer material - polyaniline, doped with various chemical additives. Production of the polymer material with p- and n- conductivity is realised by a process of electropolymerisation from a water solution of aniline and hydrochloric acid with chemical additives.
EFFECT: increase of productivity coefficient.
SUBSTANCE: invention refers to thermoelectric devices. The invention concept is as follows: the method includes manufacturing of rods of thermoelectric material by hot extrusion. Thereafter lateral side of rods is treated. Water paint compound with fluorine rubber is applied to the rod lateral sides by means of cathodic or anodic electrodeposition in order to obtain a protective polymer coating. Then the rods are washed and cured thermally. The rods are cut in order to obtain semiconductor paths of the preset length. Antidiffusion metal coating is applied to butt ends of the obtained semiconductor paths so that the edge touches the protective polymer coating without crossing it. The single- or multi-cascade thermoelectric module contains semiconductor paths of N- and P-conductivity so that they are located in parallel and do not tough each other. Semiconductor paths of N- and P-conductivity are manufactured as per the method specified above.
EFFECT: improving chemical, thermal and mechanical resistivity, providing high adhesion and elasticity for polymer coating of thermoelectric paths.
9 cl, 11 dwg
SUBSTANCE: rods of thermoelectric material based on solid solutions of Bi2Te3-Bi2Se with n-type conductivity, effectiveness ZT>1.2 and mechanical strength of not less than 150 MPa are made through mechanical activation synthesis of a ternary solid solution of Bi2Te2.85Se0.15 with n-type conductivity from starting components. The donor alloy used is Bi11Sei2Cl9. The obtained material then undergoes preliminary cold pressing into a briquette and hot extrusion under pressure through a draw plate in two steps. First, the briquette enters the conical part of the draw plate at pressure of 250-350 MPa, where it undergoes plastic deformation at temperature of 350-420°C with elongation ratio of 8-11. At the same pressure, the formed rod enters the equal channel part of the draw plate, where it undergoes further plastic deformation by equal channel multi-angular pressing with deformation ratio ε<1 at temperature which is 50-70°C higher than temperature in the conical part of the draw plate. The thermoelectric rod then undergoes post-extrusion annealing at temperature of 300-350°C for 1-5 days.
EFFECT: improved method.
2 cl, 2 tbl, 1 dwg
SUBSTANCE: monocrystalline films of a solid bismuth-antimony solution are obtained using zonal recrystallisation of vacuum sputtered, uniform-composition polycrystalline films of a solid bismuth-antimony solution under a protective coating, the melting point of which is higher than that of the obtained film, at a higher rate of zone movement than when growing bulk monocrystals (for films of solid bismuth-antimony solutions higher than 1 cm/h versus 0.05 mm/h for bulk crystals).
EFFECT: invention enables to obtain monocrystalline films of a solid bismuth-antimony solution with uniform volume distribution of components.
FIELD: thermoelectric devices for manufacturing thermoelectric refrigerators and generators.
SUBSTANCE: proposed method for switching arms of thermocouples depending for their operation on Peltier effect includes formation of block of rectangular arms, covering of butt-ends of arms with switching layers, and their connection by soldering to metal buses. Nickel switching layers and nickel-copper alloy shielding coating having thickness of 0.1-0.2 and 0.3-0.5% of arm length, respectively, are applied by chemical method from aqueous solutions. Nickel and nickel-copper alloy are deposited from alkali and ammonia solutions at temperature of 97-99 °C and pH of 8.5-9.5. Nickel plating process is initiated by holding block in contact with aluminum or with metal of iron subgroup for 20-30 s which is broken in 4-5 s upon process initiation recognized by effervescence of gas bubbles.
EFFECT: facilitated procedure, enhanced reliability of arm switching.
1 cl, 1 dwg
FIELD: thermal electricity; thermopile manufacture.
SUBSTANCE: proposed method includes manufacture of n and p wafers by compressing powders of semiconductors at temperature not to exceed 150 0C and pressure of 1 to 2 t/cm2. Compression is made in direction of thermopile heat flux. Box-shaped magazine is made of plastic conducting material. Slits are made on opposing walls at distance equal to total thickness of wafers and their insulating shims. Box is filled with alternating n and p wafers. The latter are separated by insulating shims. Upon filling the box with shims workpiece obtained is additionally compressed at high pressure of 3 to 5 t/cm2 and temperature of 350 to 500 0C in direction parallel to contact surfaces of switching buses and wafers. Upon removal of solid walls of box workpiece obtained in this way is cut into thermopiles in direction perpendicular to that of slits.
EFFECT: enhanced productivity of method and reduced contact resistance.
FIELD: temperature measurements.
SUBSTANCE: proposed process includes laser welding to form thermopile with desired inherent resistance and generated thermal emf signal value; placement of thermopile in cylindrical case of desired size followed by its sealing; and electrical connection of thermopile leads to control unit. Optimal pre-selection of thermopile hot junctions and sectional area of heat electrode wire is effected by means of mathematical simulation of thermal process.
EFFECT: enhanced labor productivity in thermogenerator manufacture; enhanced operating reliability of the latter.
3 cl, 5 dwg
FIELD: thermoelectric instrumentation engineering.
SUBSTANCE: proposed method includes vibratory placement of components one after another into changeable magazine channels throughout their entire length followed by locking these components in horizontal and vertical planes. Filled-up magazines are assembled in stack so that smooth surface of one magazine is disposed on channels-bearing surface of other magazine. Stack with channel holes is disposed perpendicular to soldered board plane with clearance between them equal to height of single component. Then components are squeezed out of stack onto board from their closest series in series-by-series manner. Device for placing components has vibration cup with helical grooves, splitter, and component discharge chute, table with linear vibrator and stepping drive, as well as table-mounted changeable magazine with channels. One of magazine channels is disposed coaxially with respect to discharging chute. Facility for placing n and p components has stacked changeable magazines with longitudinal channels. Magazines are placed with their smooth surface disposed on channels-bearing surface of next magazine. Each magazine has lock in the form of spring plate with comb mounted on magazine for turning in vertical plane. Comb teeth are disposed in channels at points where components are discharged from channels. Comb-like pusher is installed in channels on lock mounting end.
EFFECT: enhanced productivity, reliability, and yield of manufacturing process; facilitated assembly and adjustment of module.
7 cl, 6 dwg
FIELD: thermoelectric circuits of instruments based on the zee-beck effect, applicable for suppression of interference at reception of signals on temperature with the aid of thermocouples.
SUBSTANCE: the free ends of homogeneous electrodes of a four-electrode thermocouple are directly or indirectly combined. The signals from the free ends of homogeneous electrodes are summed up. The figure formed by homogeneous electrodes of the first type including the electrodes proper and the space between them, even partially, are positioned in space between them, even partially, are positioned in space between the homogeneous electrodes of another type, mainly symmetrically. The circuits of the homogeneous electrodes are balanced, for example, according to their resistance. To this end, a device for balancing, for example, of their resistances is introduced in the circuit of homogeneous electrodes. At manufacture of a thermocouple the electrodes are combined in one working junction. The electrodes are positioned in four longitudinal guides, for example, holes or slots of an insulating, mainly ceramic, tube or bar.
EFFECT: reduced share of electromagnetic interference in the thermocouple signal.
6 cl, 3 dwg
FIELD: thermoelectric instrumentation engineering; running curve of thermal cell leg temperature as function of electric current.
SUBSTANCE: leg under investigation is placed in evacuated chamber. One of butt-end surfaces of leg contacts switching wafer whose temperature is controlled. Other end surface of leg contacts reference specimen in the form of flexible bus of high heat conductivity whose loose end contacts other switching wafer cooled by cooler of adjustable cold productivity. Two junctions of differential thermocouple electrically connected to compensating microvoltmeter or to null-element are installed at respective points of contact between leg under investigation and second switching wafer. Electric current is passed through circuit set up of first switching wafer, leg under investigation, reference specimen, and second switching wafer. Signal is picked off differential thermocouple and set to zero by varying temperature of second switching wafer by means of cooler. Temperature difference through leg height is recorded when this signal equals zero. Cold productivity of leg is found from equation Q0 = IU/2, where I and U are current and voltage drop across flexible bus additionally measured by microvoltmeter, respectively. Differential thermocouple used for running ΔT = f(I) curve at zero cold productivity is made in the form of three-layer switching wafer made of copper-constant-copper strips and placed between leg under investigation and reference specimen. Copper strips are connected through copper contact wires to compensating microvoltmeter.
EFFECT: ability of dispensing with measurements in legs already assembled in thermal cell; enhanced measurement accuracy.
1 cl, 2 dwg
FIELD: thermoelectric energy conversion; thermoelectric module quality evaluation.
SUBSTANCE: module is installed in measuring-temperature cabinet and connected to measuring circuit. Low ac current is supplied to module for resistance measurements and low dc current, for thermoelectric quality evaluation until steady state Seebeck voltage is set up; time constant of thermoelectric module is found by measuring time interval between low dc current supply to module and steady state Seebeck voltage set-up moment. Results obtained are compared with standard values. Comparison results are used for diagnosing thermoelectric module quality.
EFFECT: enhanced reliability and precision of control; enlarged functional capabilities for trouble shooting.
1 cl, 4 dwg, 4 tbl
FIELD: thermoelectric instrumentation engineering; electrochemical method for applying anti-diffusion barrier.
SUBSTANCE: proposed method includes chemical treatment of plates and electrochemical nickel-plating of plate surfaces. Chemical treatment is conducted in three steps: first plates are treated with alkali solution, then with solution incorporating mixture of sulfuric and nitric acids doped with iodine ions, and finally with solution incorporating mixture of hydrofluoric and sulfuric acids. Prior to electrochemical deposition of nickel surface layers of plates are subjected to electrochemical etching in electrolyte for nickel-plating by uniformly increasing cathodic current density to 10 - 50 mA/cm2 for 1.0 = 1.5 minutes.
EFFECT: enhanced adhesive properties of anti-diffusion barrier.
FIELD: thermoelectric generators, refrigerating plants, heat pumps.
SUBSTANCE: p and/or n circuits of apparatus designed for direct or inverse heat-to-power conversion are produced using compound that incorporates magnesium, silicon, lead, and barium. This compound also incorporates one or more doping materials.
EFFECT: enhanced efficiency of energy conversion.
22 cl, 2 dwg
FIELD: thermoelectric materials.
SUBSTANCE: source alloy material incorporating rare earth metal R which is one of elements chosen among La, Ce, Pr, Nb, Sm, Eu, and Yb, transition metal T which is one of elements chosen among Fe, Co, Ni, Os, Ru, Pb, Pt, and Ag, as well as metal antimony Sb are melted. Melt is quickly cooled down by way of strip casting at cooling rate of 102 to 104 °C per second as measured at melt temperature ranging up to 800 °C until hardened product is attained. This product is essentially skutterudite based interstitial alloy suited to use for thermoelectric component.
EFFECT: enlarged quantity of alloy of almost uniform metallographic structure produced without additional heat treatment, reduced cost of thermoelectric cell manufacture.
7 cl, 3 dwg