Abstract: A three-dimensional modeling device models a three-dimensional object by irradiating a powdered material with an electron beam to melt and stack the powdered material. The three-dimensional modeling device includes a beam emitting unit that irradiates the powdered material with the electron beam by emitting the electron beam. The beam emitting unit irradiates the powdered material with the electron beam while scanning the electron beam in a direction orthogonal to a contour line of a modeling region in at least a contour portion of the modeling region that is a cross-section of the object.

Abstract: An additive manufacturing device is an additive manufacturing device manufacturing an additively manufactured article by melting or sintering layered powder by partially applying energy to the powder. The additive manufacturing device includes a powder holding unit holding the layered powder, a heating unit preheating the powder held by the powder holding unit, a reflection unit where a reflective film including a reflective surface is disposed, the reflective surface reflecting radiant heat radiated from an object including at least one of the powder and the additively manufactured article to the powder holding unit side, and a reflective surface update unit disposing a new reflective surface in the reflection unit by moving the reflective film.

Abstract: An additive manufacturing device is an additive manufacturing device manufacturing an additively manufactured article by melting or sintering layered powder by partially applying energy to the powder. The additive manufacturing device includes a powder holding unit holding the layered powder, a heating unit preheating the powder held by the powder holding unit, a reflection unit where a reflective film including a reflective surface is disposed, the reflective surface reflecting radiant heat radiated from an object including at least one of the powder and the additively manufactured article to the powder holding unit side, and a reflective surface update unit disposing a new reflective surface in the reflection unit by moving the reflective film.

Abstract: An additive manufacturing device performs manufacturing of an additively manufactured article by supplying a powder material to an irradiation region of an electron beam, laying and leveling the powder material, irradiating the powder material with the electron beam, and melting the powder material. The additive manufacturing device includes a beam emitting unit emitting the electron beam and irradiating the powder material with the electron beam, an accommodation tank capable of accommodating the powder material and supplying the powder material to the irradiation region of the electron beam, and a first heater attached to the accommodation tank and heating the powder material accommodated in the accommodation tank.

Abstract: An additive manufacturing device performs manufacturing of an additively manufactured article by supplying a powder material to an irradiation region of an electron beam, laying and leveling the powder material, irradiating the powder material with the electron beam, and melting the powder material. The additive manufacturing device determines whether or not the powder material has scattered during manufacturing of the article. When it is determined that the powder material has scattered, an irradiation region R is heated by a heater before a new powder material is supplied to the irradiation region R. Manufacturing of the article is restarted after the new powder material has been supplied to the heated irradiation region.

Abstract: In a method of arresting fatigue crack growth in a metal member, a hole is formed beside a tip portion of a fatigue crack with respect to a crack extension direction, in a metal member body, in which the fatigue crack occurs due to an action of applied cyclic tensile stress. Then, a press-fit object being higher in stiffness than the metal member body and larger in external size than the hole is press-fitted into the hole. Compressive stress is made to act on the tip portion of the fatigue crack from directions lateral to the crack extension direction.

Abstract: In a method of arresting fatigue crack growth in a metal member, a hole is formed beside a tip portion of a fatigue crack with respect to a crack extension direction, in a metal member body, in which the fatigue crack occurs due to an action of applied cyclic tensile stress. Then, a press-fit object being higher in stiffness than the metal member body and larger in external size than the hole is press-fitted into the hole. Compressive stress is made to act on the tip portion of the fatigue crack from directions lateral to the crack extension direction.