US 12,247,275 B2
Method for the additive manufacturing of an object from a maraging steel powder
Harald Leitner, Kindberg (AT); Klaus Sammt, Spielberg (AT); and Horst Zunko, Langenwang (AT)
Assigned to voestalpine BOHLER Edelstahl GmbH & Co. KG, Kapfenberg (AT)
Appl. No. 16/956,731
Filed by voestalpine BOHLER Edelstahl GmbH & Co. KG, Kapfenberg (AT)
PCT Filed Dec. 19, 2018, PCT No. PCT/EP2018/085788
§ 371(c)(1), (2) Date Jun. 22, 2020,
PCT Pub. No. WO2019/121879, PCT Pub. Date Jun. 27, 2019.
Claims priority of application No. 10 2017 131 218.8 (DE), filed on Dec. 22, 2017.
Prior Publication US 2023/0220527 A1, Jul. 13, 2023
Prior Publication US 2023/0392243 A2, Dec. 7, 2023
Int. Cl. C22C 38/50 (2006.01); B22F 10/14 (2021.01); B22F 10/28 (2021.01); B22F 10/64 (2021.01); B33Y 10/00 (2015.01); B33Y 70/00 (2020.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/06 (2006.01); C22C 38/42 (2006.01); C22C 38/44 (2006.01)
CPC C22C 38/50 (2013.01) [B22F 10/14 (2021.01); B22F 10/28 (2021.01); B22F 10/64 (2021.01); B33Y 70/00 (2014.12); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C22C 38/42 (2013.01); C22C 38/44 (2013.01); B33Y 10/00 (2014.12)] 25 Claims
OG exemplary drawing
 
1. A method for producing an article out of a maraging steel, comprising the steps of:
providing a steel powder having the following composition in M-%:
C=0.01-0.05
Si=0.4-0.8
Mn=0.1-0.5
Cr=12.0-13.0
Ni=9.5-10.5
Mo=0.5-1.5
Ti=0.5-1.5
Al=0.5-1.5
Cu=0.01-0.05
Residual consisting of iron and smelting-induced impurities;
forming an article from the steel powder using a powder additive production process;
optionally solution annealing the article at a temperature exceeding 875° C.; and
subjecting the article to an aging heat treatment to yield a hardness greater than 50 HRC and a retransformed austenite content of 4% to 8% by volume;
wherein the hardness greater than 50 HRC is achieved both without the solution annealing, and with the solution annealing at a temperature exceeding 875° C.