An additive manufacturing apparatus utilizing combined electron beam selective melting and electron beam cutting. One electron beam emitting, focusing, and scanning device (6) is capable of emitting electron beams (67, 68) in three modes of heating, selective melting, and electron beam cutting. The electron beam in the heating mode is emitted to scan and preheat a powder bed (7). The electron beam (67) in the selective melting mode is emitted to scan and melt powder (71) in a section outline to form a section layer of a component. The electron beam (68) in the electron beam cutting mode is emitted to perform one or more cutting scans on inner and outer outlines (74, 75) of a section of the component to obtain accurate and smooth inner and outer outlines of the section. The heating, melting deposition, and outline cutting processes are repeated to obtain a required three-dimensional physical component.

An additive manufacturing apparatus utilizing combined electron beam selective melting and electron beam cutting. One electron beam emitting, focusing, and scanning device (6) is capable of emitting electron beams (67, 68) in three modes of heating, selective melting, and electron beam cutting. The electron beam in the heating mode is emitted to scan and preheat a powder bed (7). The electron beam (67) in the selective melting mode is emitted to scan and melt powder (71) in a section outline to form a section layer of a component. The electron beam (68) in the electron beam cutting mode is emitted to perform one or more cutting scans on inner and outer outlines (74, 75) of a section of the component to obtain accurate and smooth inner and outer outlines of the section. The heating, melting deposition, and outline cutting processes are repeated to obtain a required three-dimensional physical component.

Methods, apparatus, and systems for fabricating diffractive structures on gemstones for high optical performance are provided. In one aspect, a method includes obtaining a plurality of gemstone characteristics of a gemstone, determining that the gemstone exhibits each of the plurality of gemstone characteristics within a respective predetermined range, identifying a diffractive structure setting associated with a combination of the respective predetermined ranges for the plurality of gemstone characteristics, and fabricating diffractive structures on the gemstone according to the diffractive structure setting.

The present application relates to the technical field of 3D printing apparatus, and discloses an electron beam melting and cutting composite 3D printing apparatus which comprises a box and an electron beam gun, in which the box has a cavity formed therein, the cavity is provided therein with a cutting structure, a first Y-direction guide rail and a Y-direction movable platform, the electron beam gun has an emitting head formed in the cavity, the Y-direction movable platform is provided thereon with a Z-direction movable platform, the Z-direction movable platform is provided thereon with a powder spreading structure, the cutting structure has a cutting head, a shielding case is arranged between the emitting head and the Z-direction movable platform, the emitting head of the electron beam gun is inserted in an upper opening of the shielding case, and a lower opening of the shielding case is aligned with the Z-direction movable platform.

The present application relates to the technical field of 3D printing apparatus, and discloses an electron beam melting and cutting composite 3D printing apparatus which comprises a box and an electron beam gun, in which the box has a cavity formed therein, the cavity is provided therein with a cutting structure, a first Y-direction guide rail and a Y-direction movable platform, the electron beam gun has an emitting head formed in the cavity, the Y-direction movable platform is provided thereon with a Z-direction movable platform, the Z-direction movable platform is provided thereon with a powder spreading structure, the cutting structure has a cutting head, a shielding case is arranged between the emitting head and the Z-direction movable platform, the emitting head of the electron beam gun is inserted in an upper opening of the shielding case, and a lower opening of the shielding case is aligned with the Z-direction movable platform.

A method of raster scanning a surface of an object using a particle beam comprises determining a basic set of raster points within a surface; determining a surface portion of the surface of the object, wherein the surface portion is to be raster scanned; ordering a set of raster points of the basic set located within the surface portion; and scanning of the surface portion by directing the particle beam onto the raster points of the ordered set in an order corresponding to an order of the raster points in the ordered set from the outside to the inside, i.e. starting from the boundary of the surface portion towards its center, or in the reverse order, i.e. from the inside to the outside.

A method of raster scanning a surface of an object using a particle beam comprises determining a basic set of raster points within a surface; determining a surface portion of the surface of the object, wherein the surface portion is to be raster scanned; ordering a set of raster points of the basic set located within the surface portion; and scanning of the surface portion by directing the particle beam onto the raster points of the ordered set in an order corresponding to an order of the raster points in the ordered set from the outside to the inside, i.e. starting from the boundary of the surface portion towards its center, or in the reverse order, i.e. from the inside to the outside.

A medical implant such as a self-expanding shape memory alloy stent with a strut matrix formed by cut patterns in a wall of a tubular workpiece can be enhanced by arranging for the line of the laser beam when cutting the struts to be one that does not pass through the longitudinal rotational axis of the tubular workpiece. Such off-axis cutting can modify the cross-sectional shape and area of each strut, along its length. Such modulation can enhance the fatigue resistance of the stent matrix, or increase the radial force that the stent matrix is capable of exerting on bodily tissue within which it is implanted.

A medical implant such as a self-expanding shape memory alloy stent with a strut matrix formed by cut patterns in a wall of a tubular workpiece can be enhanced by arranging for the line of the laser beam when cutting the struts to be one that does not pass through the longitudinal rotational axis of the tubular workpiece. Such off-axis cutting can modify the cross-sectional shape and area of each strut, along its length. Such modulation can enhance the fatigue resistance of the stent matrix, or increase the radial force that the stent matrix is capable of exerting on bodily tissue within which it is implanted.

There is provided a shield plate fabrication apparatus capable of fabricating a shield plate easily. The shield plate is included in a sample milling apparatus which mills a sample by shielding a part of the sample with the shield plate and irradiating the sample with a charged particle beam. The fabrication apparatus includes: a base plate holding shaft for rotatably holding a base plate and winding tape around the base plate; and a tension mechanism for applying tension to the tape while it is being wound around the base plate.