US 11,926,091 B2
In situ partially degradable separation interface for fabrication of complex near net shape objects by pressure assisted sintering
Eugene Olevsky, San Diego, CA (US); and Charles Maniere, Toulouse (FR)
Assigned to UNITED STATES OF AMERICA has certain rights in the invention from DOE Grant No. DE-SC0008581, Washington, DC (US); and San Diego State University, San Diego, CA (US)
Appl. No. 17/042,176
Filed by Eugene Olevsky, San Diego, CA (US); and Charles Maniere, Toulouse (FR)
PCT Filed Mar. 27, 2019, PCT No. PCT/US2019/024382
§ 371(c)(1), (2) Date Sep. 27, 2020,
PCT Pub. No. WO2019/191299, PCT Pub. Date Oct. 3, 2019.
Claims priority of provisional application 62/648,433, filed on Mar. 27, 2018.
Prior Publication US 2021/0016499 A1, Jan. 21, 2021
Int. Cl. B29C 64/153 (2017.01); B22F 10/00 (2021.01)
CPC B29C 64/153 (2017.08) [B22F 10/00 (2021.01)] 6 Claims
OG exemplary drawing
 
1. A process for producing a sintered powder manufactured item, comprising the steps:
STEP 1-performing 3D printing of a polymer shell model, of a manufactured item, the polymer shell model prepared using an organic material selected from the group consisting of acrylonitrile butadiene styrene (ABS), polycarbonate (PC), polylactic acid (PLA), high-density polyethylene (HDPE), PC/ABS, polyphenylsulfone (PPSU) and high impact polystyrene (HIPS);
STEP 2-placing the polymer shell model in a die chamber having a tool punch;
STEP 3-loading powder sintering material into the die chamber on the polymer shell model to create a powder-encased polymer shell model, the powder sintering material selected from the group consisting of stainless steel powder, titanium alloy powder, chromium alloy powder, nickel alloy powder, aluminum alloy powder, mixed metal powder, and ceramic powder, the powder sintering material having a particle size of 20-200 microns;
STEP 4-vacuum or oxygen/hydrogen free atmosphere heating of the powder-encased polymer shell model to decompose the polymer shell model creating a graphite interface layer, said heating at 600-1000° C. for metal powder sintering material and 1000-2200° C. for ceramic powder sintering material;
STEP 5-sintering of the powder-encased polymer shell model; and
STEP 6-releasing a sinter-powder cast manufactured item from the die chamber using the tool punch.