Laminate shaped article, method for manufacturing the same, and metal powder for laminate shaping

A method for manufacturing laminate shaped article forming an article by a laminate shaping step in which an operation of spreading a metal powder made of a maraging steel on a stage and an operation of scanning and irradiating a heat source on the metal powder spread on the stage are repeatedly performed, the maraging steel is made of a component composition as following by mass %:

• C:
• 0.1% or less, Ni:
• 14-22%, Co:
• 0-20%, Mo:
• 0.1-15.0%, Ti:
• 0.1-5.0%, Al:
• 3.0% or less, and the balance comprising Fe and impurities, wherein
• a heat source output is 250-330 W and a scanning speed is 480-3000 mm/sec when the heat source is scanned and irradiated on the metal powder.

A metal powder for laminate shaping, which is made of a maraging steel and has a median diameter D50 of 200 μm or less, the maraging steel is made of a component composition as following by mass %:

• C:
• 0.1% or less, Ni:
• 14-22%, Co:
• 0-5%, Mo:
• 0.1-15.0%, Ti:
• 0.1-5.0%, Al:
• 3.0% or less, and the balance comprising Fe and impurities.