US 12,269,094 B2
Method for manufacturing turbomachine parts by MIM molding
Hugo Sistach, Moissy-Cramayel (FR); Cédric Pierre Jacques Colas, Moissy-Cramayel (FR); and Terence Grall, Moissy-Cramayel (FR)
Assigned to SAFRAN AIRCRAFT ENGINES, Paris (FR)
Appl. No. 17/616,927
Filed by SAFRAN AIRCRAFT ENGINES, Paris (FR)
PCT Filed Jun. 7, 2020, PCT No. PCT/FR2020/050966
§ 371(c)(1), (2) Date Dec. 6, 2021,
PCT Pub. No. WO2020/245551, PCT Pub. Date Dec. 10, 2020.
Claims priority of application No. 1906075 (FR), filed on Jun. 7, 2019.
Prior Publication US 2022/0314317 A1, Oct. 6, 2022
Int. Cl. B22F 3/22 (2006.01); B22F 3/10 (2006.01); B22F 5/04 (2006.01); B22F 7/06 (2006.01); B33Y 10/00 (2015.01); B33Y 30/00 (2015.01); B33Y 80/00 (2015.01); F01D 9/04 (2006.01)
CPC B22F 3/225 (2013.01) [B22F 3/1021 (2013.01); B22F 5/04 (2013.01); B22F 7/062 (2013.01); F01D 9/042 (2013.01); B22F 2007/066 (2013.01); B33Y 10/00 (2014.12); B33Y 30/00 (2014.12); B33Y 80/00 (2014.12); F05D 2230/21 (2013.01); F05D 2230/22 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A method for manufacturing an aircraft or turbomachine part for an aircraft, by injection molding of at least a first green element and a second green element of the said part, comprising:
a) preparing a mixture of a powder and a polymeric binder, which is liquid or molten, for each of the first and second elements, adapted to enable the powder grains to be bonded together,
b) injecting the prepared mixtures into molds adapted to the shape of the first and second elements, respectively, to obtain two green blanks of the first and second elements, respectively,
c) removing the two green blanks from the respective molds once the binder has become consistent,
d) heating an additional amount of binder, then heating at least one assembly area of at least one of the two green blanks by applying the additional amount of binder at the location of the said assembly area, the at least one assembly area being located at the interface between the said two green blanks to be assembled together, so that molten binder is present at the location of the said assembly area, the said assembly area of at least one of the green blanks to be assembled together is heated by supplying an additional quantity of binder at the location of the said assembly area, and then
e) assembling the two green blanks together through the said at least one assembly area to obtain an overall green blank of the said part, then
f) removing at least part of the binder from the overall green blank to obtain a debonded overall green blank, and
g) carrying out a sintering treatment on the debonded overall green blank, wherein the said part to be manufactured is a turbomachine compressor rectifier sector or a turbomachine turbine nozzle sector, and the said two green blanks, respectively, of the first element and the second element, are green blanks, respectively:
of at least one part of the rectifying vane of the said rectifier sector or nozzle sector, and
of a sector of an outer ring or a sector of an inner ring of the said rectifier sector or nozzle sector, with which one end of the said at least one part of the rectifying vane is to be assembled in step e).