Screening method for diffusion barrier layer of thermoelectric component

Abstract

The invention relates to a screening method for a diffusion barrier layer of a thermoelectric component. The method comprises the steps of (1) determining a candidate barrier layer material of the thermoelectric component, (2) uniformly mixing candidate barrier layer material powder and thermoelectric material powder as a matrix according to a certain ratio to obtain mixed powder, (3) densifying the obtained mixed powder to obtain a dense body, (4) performing heat persistence treatment on the dense body, and (5) observing the interface diffusion between each barrier layer material particle ina sample which is subjected to the heat persistence treatment and a matrix material and screening out a barrier layer material that is stable to the interface of the matrix material.

Description

technical field

[0001] The invention belongs to the technical field of thermoelectric components, and in particular relates to a screening method for diffusion barrier layer materials of thermoelectric components. Background technique

[0002] During the service process of thermoelectric components, there is often obvious interdiffusion and reaction at the interface between the high-temperature terminal electrode of the device and the thermoelectric material, and various interfacial diffusion layers are formed. Compared with electrode materials, the thermal and electrical properties of the diffusion layer itself are usually poor, and the growth process of the interface diffusion layer is often accompanied by volume effects, which not only reduces the density of the diffusion layer, but also aggravates the formation of microscopic pores and cracks at the interface , resulting in a decrease in the stability of the component interface and deterioration in service performance. ...

Examples

Embodiment 1

[0054] Take the component as Yb 0.3 co 4 Sb 12 n-type skutterudite powder (n-SKD) 2.5g, take Ti(4N, 45um), Zr(3N, 75um), Hf(3N, 75um), V(3N, 75um), Nb(4N, 45um) , Ta, Cr (3N5, 150um), Mo (3N, 75um), W (3N, 75um) powders, each 0.02g, mixed with n-SKD powder evenly. Put the mixed powder into a graphite mold with a diameter of 12.7mm, put the mold into an SPS sintering system, and conduct spark plasma rapid sintering under vacuum: the chamber pressure is <10Pa, the sintering pressure is 64MPa, the heating rate is 80°C / min, and the sintering temperature is 620°C , the holding time is 10 min, the cooling rate is 60 °C / min, and the temperature is lowered to 200 °C and then cooled in the furnace to obtain a densified co-sintered sample, which contains the interface between the above nine candidate barrier particles and the n-SKD matrix material. The above-mentioned co-sintered samples were sealed in a vacuum quartz tube and heated at 650°C for 2 days. The surface of the heat-dura...

Embodiment 2

[0058] Take the component as Yb 0.3 co 4 Sb 12 Put 4g of n-type skutterudite powder (n-SKD) into a graphite mold with a diameter of 12.7mm, put the mold into an SPS sintering system, and perform discharge plasma rapid sintering under vacuum: chamber pressure -3 Pa, continue pumping, and start to heat up at the same time. After 30 minutes, the chamber temperature reaches 200°C, keep it warm for half an hour, then feed high-purity Ar, and sputter the Mo target with 1.5kW power for 40 minutes under the chamber pressure of 1.1Pa. After the sputtering is over, the equipment is turned off, the sample is cooled with the furnace, and the chamber temperature is lower than 70°C, then the cabin is opened and the sample is taken out. The sample was cut by wire cutting to obtain the structure Mo / Yb 0.3 co 4 sb 12 The thermoelectric element and the corresponding macroscopic interface. The above-mentioned components were sealed in a vacuum quartz tube, and heated at 650°C for 2 days. T...

technical field

[0001] The invention belongs to the technical field of thermoelectric components, and in particular relates to a screening method for diffusion barrier layer materials of thermoelectric components. Background technique

[0002] During the service process of thermoelectric components, there is often obvious interdiffusion and reaction at the interface between the high-temperature terminal electrode of the device and the thermoelectric material, and various interfacial diffusion layers are formed. Compared with electrode materials, the thermal and electrical properties of the diffusion layer itself are usually poor, and the growth process of the interface diffusion layer is often accompanied by volume effects, which not only reduces the density of the diffusion layer, but also aggravates the formation of microscopic pores and cracks at the interface , resulting in a decrease in the stability of the component interface and deterioration in service performance. ...

Examples

Embodiment 1

[0054] Take the component as Yb 0.3 co 4 Sb 12 n-type skutterudite powder (n-SKD) 2.5g, take Ti(4N, 45um), Zr(3N, 75um), Hf(3N, 75um), V(3N, 75um), Nb(4N, 45um) , Ta, Cr (3N5, 150um), Mo (3N, 75um), W (3N, 75um) powders, each 0.02g, mixed with n-SKD powder evenly. Put the mixed powder into a graphite mold with a diameter of 12.7mm, put the mold into an SPS sintering system, and conduct spark plasma rapid sintering under vacuum: the chamber pressure is <10Pa, the sintering pressure is 64MPa, the heating rate is 80°C / min, and the sintering temperature is 620°C , the holding time is 10 min, the cooling rate is 60 °C / min, and the temperature is lowered to 200 °C and then cooled in the furnace to obtain a densified co-sintered sample, which contains the interface between the above nine candidate barrier particles and the n-SKD matrix material. The above-mentioned co-sintered samples were sealed in a vacuum quartz tube and heated at 650°C for 2 days. The surface of the heat-dura...

Embodiment 2

[0058] Take the component as Yb 0.3 co 4 Sb 12 Put 4g of n-type skutterudite powder (n-SKD) into a graphite mold with a diameter of 12.7mm, put the mold into an SPS sintering system, and perform discharge plasma rapid sintering under vacuum: chamber pressure -3 Pa, continue pumping, and start to heat up at the same time. After 30 minutes, the chamber temperature reaches 200°C, keep it warm for half an hour, then feed high-purity Ar, and sputter the Mo target with 1.5kW power for 40 minutes under the chamber pressure of 1.1Pa. After the sputtering is over, the equipment is turned off, the sample is cooled with the furnace, and the chamber temperature is lower than 70°C, then the cabin is opened and the sample is taken out. The sample was cut by wire cutting to obtain the structure Mo / Yb 0.3 co 4 sb 12 The thermoelectric element and the corresponding macroscopic interface. The above-mentioned components were sealed in a vacuum quartz tube, and heated at 650°C for 2 days. T...

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