Methods and apparatuses for manufacturing are disclosed, including (a) providing an apparatus having: a laser; scanner; powder injection system; powder spreading system; dichroic filter; imager-and-processor; and computer; (b) programming the computer with specifications of a sample; (c) using the computer to set initial parameters based on the sample specifications; (d) adjusting a stage to position the sample; (e) focusing and scanning electromagnetic radiation onto the sample while powder is concurrently injected onto the sample in order to deposit a layer; (f) capturing two-dimensional images of the sample and probing the sample to determine whether the deposited layer was manufactured per the specifications; (g) use the computer to adjust the three-dimensional manufacturing parameters based on the determination made in step (f) prior to additively manufacturing a subsequent layer or making repairs; and (h) repeating steps (d), (e), (f), and (g) until the manufacture is complete. Other embodiments are described and claimed.

A three-dimensional printing system for fabricating a three-dimensional article includes a motorized build platform, a dispensing module, a pulsed light source, an imaging module, a movement mechanism, and a controller. The imaging module receives radiation from the pulsed light source and includes a two-dimensional mirror array. The movement mechanism imparts lateral motion between the imaging module and the build platform. The controller is configured to operate the motorized build platform and the dispensing module to form a layer of build material at a build plane, operate the movement mechanism to laterally scan the imaging module over the build plane, operate the pulsed light source to generate a sequence of radiation pulses that illuminate the mirror array, and operate the mirror array to selectively image the build material.

A three-dimensional printing system for fabricating a three-dimensional article includes a motorized build platform, a dispensing module, a pulsed light source, an imaging module, a movement mechanism, and a controller. The imaging module receives radiation from the pulsed light source and includes a two-dimensional mirror array. The movement mechanism imparts lateral motion between the imaging module and the build platform. The controller is configured to operate the motorized build platform and the dispensing module to form a layer of build material at a build plane, operate the movement mechanism to laterally scan the imaging module over the build plane, operate the pulsed light source to generate a sequence of radiation pulses that illuminate the mirror array, and operate the mirror array to selectively image the build material.

According to examples, an apparatus may include a build platform and a chamber. The chamber may support a layer forming station including a spreading component to spread a layer of build material particles onto the build platform and an agent delivery component to apply fusing agent onto selected locations on the spread layer of build material particles and a heating station including a heating component to apply energy onto the spread layer of build material particles and the applied fusing agent, in which the heating station is separated from the layer forming station. The apparatus may also include an actuator to move the chamber with respect to the build platform or vice versa while maintaining the separation between the layer forming station and the heating station.

According to examples, an apparatus may include a build platform and a chamber. The chamber may support a layer forming station including a spreading component to spread a layer of build material particles onto the build platform and an agent delivery component to apply fusing agent onto selected locations on the spread layer of build material particles and a heating station including a heating component to apply energy onto the spread layer of build material particles and the applied fusing agent, in which the heating station is separated from the layer forming station. The apparatus may also include an actuator to move the chamber with respect to the build platform or vice versa while maintaining the separation between the layer forming station and the heating station.

A method for prefabricating pore defects by controlling a SLM process, including performing laser scanning on a specified metal melt layer (LY) according to a first scan path (P1) and a second scan path. The first scan path (P1) and the second scan path (P2) have a path overlap zone (A0), the path overlap zone (A0) has a predetermined width, and laser energy input superimposed in the path overlap zone (A0) is controlled to reach a predetermined energy value, whereby keyholes are formed at a plurality of positions in a lengthwise direction of the path overlap zone (A0), the specified metal melt layer (LY) is taken as a defect layer, and the keyholes in the path overlap zone (A0) is taken as pore defects.

In one example in accordance with the present disclosure, a method is described. The example method determining parameters for a pulsed laser to generate a melt pool pattern in a three-dimensional (3D) object to produce different phases in the 3D object that vary according to the melt pool pattern. The example method also includes controlling the pulsed laser to form the 3D object in an additive manufacturing process based on the determined parameters and the melt pool pattern.

In one example in accordance with the present disclosure, a method is described. The example method determining parameters for a pulsed laser to generate a melt pool pattern in a three-dimensional (3D) object to produce different phases in the 3D object that vary according to the melt pool pattern. The example method also includes controlling the pulsed laser to form the 3D object in an additive manufacturing process based on the determined parameters and the melt pool pattern.

In example implementations, a minor assembly for a three dimensional printer is provided. The minor assembly includes a first side and a second side. The first side is symmetrical to the second side and enclose a cylindrical light source. The first side and the second side each include a first curved reflective surface and a second curved reflective surface. An end of the first curved reflective surface and a beginning of the second curved reflective surface form an edge along a surface formed by the first curved reflective surface and the second curved reflective surface.

A defect detection method includes: a step of irradiating an object with a pulsed laser beam to continuously generate ultrasonic waves in the object; and a step of detecting the presence or absence of an internal defect of the object on the basis of the presence or absence of resonance of the ultrasonic waves occurring between a surface of the object and the internal defect. In this method, the internal defect is detected on the basis of the presence or absence of resonance of the ultrasonic waves occurring between the surface of the object and the internal defect. The internal defect can be thus detected even when the internal defect is in a surface layer of the object. The detected internal defect is crack or void.