PRINTING METHOD FOR PRODUCING THERMOMAGNETIC FORM BODIES FOR HEAT EXCHANGERS

• US 20120033002A1
• Filed: 03/22/2010
• Published: 02/09/2012
• Est. Priority Date: 03/24/2009
• Status: Active Grant

• Current Assignee: BASF SE
• Original Assignee: BASF SE
• Inventors: Seeler, Fabian, Degen, Georg, Reesink, Bennie, Kaczun, Jürgen
• Granted Patent: US 9,403,323 B2
• Time in Patent Office: Days
• US Class Current: 346/74.2
• CPC Class Codes: B22F 10/12 by photopolymerisation, e.g. stereolithography [SLA] or digital light processing [DLP]
• CPC Class Codes: B22F 10/14 by jetting of binder onto a bed of metal powder
• CPC Class Codes: B22F 10/28 Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM]
• CPC Class Codes: B22F 10/32 of the atmosphere, e.g. composition or pressure in a building chamber
• CPC Class Codes: B22F 10/34 of powder characteristics, e.g. density, oxidation or flowability
• CPC Class Codes: B22F 10/38 to achieve specific product aspects, e.g. surface smoothness, density, porosity or hollow structures
• CPC Class Codes: B22F 10/64 by thermal means control of energy beam parameters for post heating B22F10/364
• CPC Class Codes: B22F 3/105 by using electric current other than for infrared radiant energy, laser radiation or plasma B22F3/11 takes precedence; by ultrasonic bonding B22F3/115 takes precedence
• CPC Class Codes: B22F 5/10 of articles with cavities or holes, not otherwise provided for in the preceding subgroups
• CPC Class Codes: B29C 64/165 using a combination of solid and fluid materials, e.g. a powder selectively bound by a liquid binder, catalyst, inhibitor or energy absorber
• CPC Class Codes: B29L 2031/18 Heat-exchangers or parts thereof
• CPC Class Codes: C09K 3/18 for application to surfaces to minimize adherence of ice, mist or water thereto rendering particulate materials free flowing, in general, e.g. making them hydrophobic B01J2/30; Thawing or antifreeze materials for application to surfaces used in liquids for heat-transfer, heat-exchange or heat-storage or for the production of heat or cold other than by combustion, e.g. radiator liquids, C09K5/00
• CPC Class Codes: C09K 5/14 Solid materials, e.g. powdery or granular
• CPC Class Codes: C22C 1/047 comprising intermetallic compounds C22C1/0441 takes precedence
• CPC Class Codes: C22C 2202/02 Magnetic
• CPC Class Codes: H01F 1/015 Metals or alloys
• CPC Class Codes: H01F 1/017 Compounds
• CPC Class Codes: Y02P 10/25 Process efficiency

Abstract

In a method for producing form bodies for heat exchangers, comprising a thermomagnetic material, said form bodies having channels for passage of a fluid heat exchange medium, a powder of the thermomagnetic material is introduced into a binder, the resulting molding material is applied to a carrier by printing methods, and the binder and if appropriate a carrier are removed subsequently and the resulting green body is sintered.

Claims

1-13. -13. (canceled)

14. A method for producing form bodies for heat exchangers, comprising:

a thermomagnetic material selected from

(1) compounds of the general formula (I)

(A_yB_y-1)_2+δ

C_wD_xE_z  

 

(I)

where

A is Mn or Co,

B is Fe, Cr or Ni,

C, D and E at least two of C, D and E are different, have a non-vanishing concentration and are selected from P, B, Se, Ge, Ga, Si, Sn, N, As and Sb,

δ

is a number in the range from −

0.2 to 0.2,

w, x, y, z are numbers in the range from 0 to 1, where w+x+z=1,

(2) La- and Fe-based compounds of the general formulae (II) and/or (III) and/or (IV)

La(Fe_xAl<sub>1−

x</sub>)₁₃H_y or La(Fe_xSi<sub>1−

x</sub>)₁₃H_y  

 

(II)

where

x is a number from 0.7 to 0.95,

y is a number from 0 to 3;

La(Fe_xAl_yCo_z)₁₃ or La(Fe_xSi_yCo_z)₁₃  

 

(III)

where

x is a number from 0.7 to 0.95,

y is a number from 0.05 to 1−

x,

z is a number from 0.005 to 0.5;

LaMn_xFe_2-xGe  

 

(IV)

where

x is a number from 1.7 to 1.95 and

(3) Heusler alloys of the MnTP type where T is a transition metal and P is a p-doping metal having an electron count per atom e/a in the range from 7 to 8.5,

(4) Gd- and Si-based compounds of the general formula (V)

Gd₅(Si_xGe<sub>1−

x</sub>)₄  

 

(V)

where x is a number from 0.2 to 1,

(5) Fe₂P-based compounds,

(6) manganites of the perovskite type,

(7) compounds which comprise rare earth elements and are of the general formulae (VI) and (VII)

Tb₅(Si_4-xGe_x)  

 

(VI)

where x=0, 1, 2, 3, 4,

XTiGe  

 

(VII)

where X=Dy, Ho, Tm,

(8) Mn- and Sb- or As-based compounds of the general formulae (VIII) and (IX)

Mn_2-xZ_xSb  

 

(VIII)

Mn₂Z_xSb<sub>1−

x</sub>  

 

(IX)

where

Z is Cr, Cu, Zn, Co, V, As, Ge,

x is from 0.01 to 0.5,

where Sb may be replaced by As when Z is not As,

said form bodies having channels for passage of a fluid heat exchange medium, which comprises introducing a powder of the thermomagnetic material into a binder, applying the resulting molding material to a carrier by printing methods selected from screenprinting, inkjet printing and rapid prototyping/3D printing and subsequently removing the binder and if appropriate the carrier, and sintering the resulting green body and wherein a plurality of different thermomagnetic materials are printed alongside one another and/or one on top of another, such that different thermomagnetic materials which exhibit a magnetocaloric effect at different temperatures are present in the same form body.

15. The method according to claim 14, wherein the three-dimensional arrangement of different thermomagnetic materials along at least one spatial axis is effected such that the result is a quasicontinuous rise or decline in the temperature at which the magnetocaloric effect occurs in each case along this at least one spatial axis.

16. The method according to claim 14, wherein the powder of the thermomagnetic material has a mean particle size in the range from 0.1 to 100 μ

m.

17. The method according to claim 14, wherein the thermomagnetic material is selected from at least quaternary compounds of the general formula (I) which, as well as Mn, Fe, P and optionally Sb, additionally comprise Ge or Si or As or Fe and Si or Ge and As or Si and As, or Ge, Si and As.

18. The method according to claim 14, wherein the channels in the form body have a mean diameter in the range from 0.1 to 2000 μ

m.

19. The method according to claim 14, wherein the channels are configured so as to provide one or more inlet and outlet orifices for the fluid heat exchange medium, and the channels are arranged such that they allow substantially homogeneous temperature control of the form body.

20. The method according to claim 14, wherein the molding material comprises additional additives for improving the mechanical properties, a corrosion resistance and/or the conductivity.

21. The method according to claim 14, wherein the printing method is rapid prototyping/3D printing.