A reset compound Mg-Si-Sn base thermal electric material and its making method

A mg-si-sn, in-situ composite technology, applied in the direction of thermoelectric device junction lead-out materials, thermoelectric device manufacturing/processing, etc., can solve the problem that the second phase of the thermoelectric material is not very good, the distribution of the second phase is not good Determining and difficult to control the distribution of two phases, etc., to achieve the effect of reducing interface pollution, reducing thermal conductivity, and improving thermoelectric performance

Inactive Publication Date: 2009-11-04
ZHEJIANG UNIV
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the two phases are generally synthesized first, and then the two phases are artificially mixed, which makes it difficult to control the distribution of the two phases, and will inevitably introduce interface contamination, which will affect the electrical properties of the material.
There are also some in-situ generated second phases, although they can reduce interface contamination, but they are all excessive metal phases and oxidized phases that appear during the synthesis process. The distribution of these second phases is also uncertain, and more importantly, these second phases Neither phase is a good thermoelectric material

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • A reset compound Mg-Si-Sn base thermal electric material and its making method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0019] Raw materials are stoichiometrically compared to Mg 2 Si 0.5 sn 0.5 After calculation and weighing, put it in a ceramic tube protected by Ar gas, heat it in a furnace at 1100°C and fully melt it, then quickly move the ceramic tube to a furnace at 860°C, and then cool it to 780°C at a cooling rate of 1°C / min. Annealed at 600°C for 100h, then mechanically ball-milled the material, then hot-pressed in vacuum at 600°C and 80MPa for 2h. The in-situ composite Mg-Si-Sn based thermoelectric material is obtained.

[0020] RigakuD / MAX-2550PC X-ray polycrystalline diffractometer (XRD) was used to analyze the phase of the sample prepared in this example, and the sample was obtained as a composite material of Si-rich phase and Sn-rich phase.

[0021] Using FEI Sirion Field Emission Scanning Electron Microscope (FESEM) to observe the microstructure of the material, such as figure 1 As shown, the surface of the sample is coated with a thin layer of 200nm. XRD and energy spectrum a...

Embodiment 2

[0024] Raw materials are stoichiometrically compared to Mg 1.992 La 0.008 Si 0.52 sn 0.48 After calculation and weighing, put it in a ceramic tube protected by Ar gas, heat it in a furnace at 1200°C and fully melt it, then quickly move the ceramic tube to a furnace at 900°C, and then cool it to 780°C at a cooling rate of 1°C / min. Annealed at 600°C for 150h, then mechanically ball-milled the material, and then vacuum hot-pressed at 600°C and 80MPa for 1h. Microstructure observation shows that the surface of the sample is covered with a 500nm thin layer. XRD and energy spectrum analysis show that the Si:Sn atomic content ratio of the Sn-rich phase is 0.35:0.65, and the Si-rich phase Si:Sn atomic content ratio is 0.7:0.3. The performance test shows that the thermal conductivity of the composite thermoelectric material is κ=1.9W·m at room temperature -1 K -1 , the Z value is 1000×10 at 800K -6 K -1 .

Embodiment 3

[0026] Raw materials are stoichiometrically compared to Mg 1.98 La 0.02 Si 0.55 sn 0.45 After calculation and weighing, put it in a ceramic tube protected by Ar gas, heat it in a furnace at 1150 °C and fully melt it, then quickly move the ceramic tube to a furnace at 900 °C, and then cool it to 780 °C at a cooling rate of 1 °C / min. Then anneal at 600°C for 100h, and then mechanically ball mill the material, then vacuum hot press at 700°C and 80MPa for 2h. Microstructure observation shows that the surface of the sample is covered with a 100nm thin layer. XRD and energy spectrum analysis show that the Si:Sn atomic content ratio of the Sn-rich phase is 0.4:0.6, and the Si-rich phase Si:Sn atomic content ratio is 0.7:0.3. The performance test shows that the thermal conductivity of the composite thermoelectric material is κ=2.0W·m at room temperature -1 K -1 , the Z value is 960×10 at 800K -6 K -1 .

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
thicknessaaaaaaaaaa
Login to view more

Abstract

The invention discloses an in-situ composite Mg-Si-Sn based thermoelectric material and a preparation method thereof. The chemical composition of the material is Mg 2-y La y Si 0.5+x Sn 0.5-x , x=0~0.08, y=0~0.1, and the structure is that the Si-rich crystal grains in the material are covered by the Sn-rich thin layer generated in situ. The composite thermoelectric material with a coating layer is obtained by in-situ reaction, the preparation method is simple, and the controllability is good. The in-situ composite Mg-Si-Sn based thermoelectric material of the present invention has better thermoelectric performance.

Description

technical field [0001] The invention relates to a semiconductor thermoelectric material and a preparation method thereof, in particular to an in-situ composite Mg-Si-Sn-based thermoelectric material and a preparation method thereof. Background technique [0002] A thermoelectric material is a semiconductor material that directly converts electrical energy and thermal energy through the movement of carriers (electrons or holes). When there is a temperature difference between the two ends of the thermoelectric material, the thermoelectric material can convert heat energy into electrical energy output; or conversely, when a current is passed through the thermoelectric material, the thermoelectric material can convert electrical energy into heat energy, and one end releases heat while the other end absorbs heat. Thermoelectric materials have a wide range of application backgrounds in refrigeration or power generation. Power generation devices made of thermoelectric materials ca...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): H01L35/14H01L35/34C22C1/04
Inventor 赵新兵张倩贺健张胜楠朱铁军T·.M·崔特
Owner ZHEJIANG UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products