Method for producing thermoelectric components by powder metallurgy

Patent metadata

Field	Value
Publication number	US-9553249-B2
Application number	US-201415025162-A
Country	US
Kind code	B2
Filing date	Aug 14, 2014
Priority date	Sep 27, 2013
Publication date	Jan 24, 2017
Grant date	Jan 24, 2017

Abstract

The invention relates to a method for producing a thermoelectric component or at least one semi-finished product of same, in which a multiplicity of thermolegs made of a thermoelectrically active material are introduced into an essentially planar substrate made of an electrically and thermally insulating substrate material such that the thermolegs extend through the substrate essentially perpendicular to the substrate plane, and in which the active material is provided in pulverulent form, is pressed to give green bodies and is then sintered within the substrate to give thermolegs. It is based on the object of refining the method of the generic type mentioned in the introduction so as to increase the freedom of choice of the thermally and electrically insulating substrate material. The object is achieved in that the pulverulent active material is pressed, in a mould arranged outside the substrate, to give green bodies, the green bodies are pushed out of the mould and into holes provided in the substrate, where they are sintered to give thermolegs.

First claim

What is claimed is:

1. A method for producing a thermoelectric component or at least one semi-finished product of same, in which a multiplicity of thermolegs made of a thermoelectrically active active material are introduced into an essentially planar substrate made of an electrically and thermally insulating substrate material such that the thermolegs extend through the substrate essentially perpendicular to the substrate plane, and in which the active material is provided in pulverulent form, is pressed to give green bodies and is then sintered within the substrate to give thermolegs, characterized in that the pulverulent active material is pressed, in a mould arranged outside the substrate, to give green bodies, the green bodies are pushed out of the mould and into holes provided in the substrate, where they are sintered to give thermolegs.

2. The method according to claim 1 , characterized in that pressing the pulverulent active material to give green bodies and pushing the green bodies into the holes in the substrate is performed with the aid of the same tools.

3. The method according to claim 2 , characterized in that the tools are at least one pair of punches which are inserted from both sides into the mould and of which one engages through the hole provided in the substrate for the respective green body.

4. The method according to claim 3 , characterized in that a plurality of moulds are combined to give a planar template, and in that, at least during pressing of the active material and insertion of the green bodies, the template lies areally on the substrate such that holes and moulds are in line with each other.

5. The method according to claim 1 , wherein the holes and the mould are of circular cylindrical shape and have essentially the same diameter.

6. The method according to claim 1 , wherein the holes are introduced into the substrate in a chip-removing manner, in particular by drilling and without the aid of cooling lubricants.

7. The method according to claim 6 , wherein the holes are blown clean after chip-removing machining, in particular using an inert gas.

8. The method according to claim 6 , wherein the substrate is held on both sides, in particular a really, by planar clamping means during introduction of the holes.

9. The method according to claim 4 , wherein one of the two clamping means is used as a template after introduction of the holes.

10. The method according to any claim 1 , wherein the substrate material is a composite material made of inorganic raw materials and binders.

11. The method according to claim 10 , wherein the composite material is constructed as a laminate, in that the inorganic raw materials are selected from the group comprising mica, perlite, phlogopite, muscovite and in that the binders are silicone or silicone resin.

12. The method according to claim 10 , wherein the thickness of the substrate is between 1 and 10 mm, preferably that it is between 1.5 and 4 mm and very preferably that the thickness is between 2 and 3 mm.

13. The method according to claim 1 , wherein the active material is an alloy which is chosen from the class of bismuth tellurides, zinc antimonides, silicides, semi-Heusler materials, and in that the particle size distribution—determined by means of laser diffraction methods—of the active material has an average particle size d 50 of between 1 and 50 μm, and in that, to set this particle size distribution, the active material is ground at a maximum temperature of between 30° C. and 50° C.

14. The method according to claim 1 , wherein the pulverulent active material is acted upon with vibration within the mould prior to pressing.

15. The method according to claims 1 , wherein the substrate, with introduced green bodies, is placed for sintering into an autoclave in which the sintering process takes place at elevated pressure and elevated temperature in an inert atmosphere, wherein in particular the gas pressure within the autoclave is lower than the pressure exerted on the pulverulent active material during pressing of the green bodies.

Assignees

• Evonik Degussa Gmbh

Inventors

• Busse Jens
• Hoch Sascha
• Kern Magdalena
• Giesseler Mareike
• Schultz Thorsten
• Stenner Patrik
• Mortensen Paw V
• Enkeshafi Ali Asghar

Classifications

• H01L35/16

  Electricity · mapped topic

• H01L35/04

  Electricity · mapped topic

• H01L35/12

  Electricity · mapped topic

• H01L35/34 Primary

  Electricity · mapped topic

• H01L35/08

  Electricity · mapped topic