Additive layer fabrication method

摘要

A selective layer melting or other additive layer fabrication method in which powdered material is fused by heating it with a pulsed laser, the pulses being modulated while the laser is traversing the substrate so as to control the thickness and/or width of the layer being formed. Initial layers of the fabrication structure may be formed more thickly than subsequent layers, e.g. by means of a CW laser, to reduce distortion. This aspect of the invention may be employed independently of the use of a pulsed laser to form the subsequent layers.

主权项

1. A method of fabricating an object, comprising:
applying heat by at least one laser beam to powdered material so as to fuse the material into a layer on a substantially flat substrate; and repeating the applying of heat by said at least one laser beam to said powdered material to build up a stack of layers one on top of the other, wherein an application of heat by said at least one laser beam is sufficient to create a local pool of molten material and wherein a layer or layers nearest to the substrate are formed to be thicker than those further from the substrate, whereby to reduce distortion in the substrate.