Manufacture and use of annealed polymer powders suitable for selective laser sintering

Abstract

A three-dimensional object may be produced with improved dimensional control by laser sintering a polymer powder having a melting point and melting onset temperature, which has been annealed prior to sintering. The initial melting onset temperature of the polymer is between 50° C. and 170° C. The polymer powder is first annealed at a temperature which is below the polymer melting point, and from 5° C. above the melting onset temperature of the polymer powder to 10° C. below the melting onset temperature. Annealing may be carried out for a period of between 2 hours and 48 hours. A layer of the annealed polymer powder is applied to a carrier; and the layer is irradiated with a laser beam in areas of the layer which correspond to the three-dimensional object to be produced. The steps of applying the annealed polymer powder and irradiating the powder are repeated sequentially until the complete three-dimensional object is prepared. The irradiating step sinters the annealed polymer powder in areas of the layer which correspond to the three-dimensional object, without sintering the annealed polymer powder in other areas.

Dependencies are inferred from the claim text.