摘要:
A molding, produced by a layer-by-layer process in which regions of respective polymer pulverulent layers are selectively melted via introduction of electromagnetic energy, where the process employs a powder which comprises at least one homopolyamide prepared via polycondensation of diamines and dicarboxylic acids, wherein the homopolyamide has an enthalpy of fusion of at least 125 J/g and a recrystallization temperature of at least 148° C.
摘要:
The present invention relates to a polymer powder composed of polyamide or of copolyamides, which also comprises flame retardant, in particular phosphonates, to a layer-by-layer process which selectively melts regions or selectively binds them, and also to moldings produced from this polymer powder. Compared with conventional products, the moldings constructed using the powder of the invention exhibit marked advantages in flammability and combustibility and drop behavior, particularly with respect to UL® (Underwriters Laboratories) classification. Furthermore, moldings produced from polymer powder of the invention have adequately good mechanical properties when compared with moldings based on polymer powders without flame retardant, in particular in terms of modulus of elasticity and tensile strain at break. In addition, these moldings also have a density close to that of injection moldings.
摘要:
A powder which is capable of being used in a layer-by-layer process in which regions of the respective pulverulent layer are selectively melted and, after cooling, are fixed, contains a mixture of diacid-regulated polyamide and diamine-regulated polyamide and/or diacid-regulated copolyamide and diamine-regulated copolyamide.
摘要:
The present invention relates to a polymer powder which comprises nylon-11, and to the use of this powder for shaping processes, and also to moldings produced from this polymer powder. The moldings constructed using the inventive powder exhibit marked advantages in terms of component properties, particularly surface finish. There are also improvements here in processing and in recycling capability when comparison is made with conventional polyamide powders.
摘要:
Composite particles comprising core particles completely or partially coated with a precipitated polymer, where the d50 median diameter of the core particles is from 1 to 70 μm and wherein the core particle is an inorganic material which does not include titanium dioxide are provided. A method to prepare the particles includes dissolution of a polymer in a solvent and precipitation of the polymer in the presence of a suspension of the core particles. Further provided is a layer by layer moulding process employing the composite particles and mouldings obtained therefrom.
摘要:
The present invention relates to a process for the bonding of material for the production of three-dimensional objects by selective heating via a laser of wavelength from 100 to 3000 nm. The beam spot may be a focused or unfocused beam spot, or may indeed be spread, as is the case with the diode laser, where the bars may have a stacked arrangement. The selectivity of the melting process is achieved via the application of an absorber to certain subregions of a layer composed of a pulverulent substrate, and then heating of the absorber by laser radiation of wavelength from 100 to 3000 nm. The heated absorber transfers the energy present therein to its surrounding pulverulent substrate, which is melted thereby and, after cooling, has firm cohesive bonding.
摘要:
The present invention relates to a polymer powder which comprises nylon-11, and to the use of this powder for shaping processes, and also to moldings produced from this polymer powder.The shaping processes are layer-by-layer processes which use powders, where regions of the respective layer are selectively melted via introduction of electromagnetic energy. The selectivity may—with no intention of restricting the invention thereto—be achieved via masks, application of inhibitors, of absorbers, or of susceptors, or via focusing of the energy introduced. After cooling, the regions then solidified can be removed in the form of moldings from the powder bed.Compared with moldings composed of conventional powders, the moldings constructed using the inventive powder by one of the inventive processes exhibit marked advantages in terms of component properties, particularly surface finish. There are also improvements here in processing and in recycling capability when comparison is made with conventional polyamide powders.
摘要:
The present invention relates to a powder which, in addition to a polymer, comprises a flame retardant based on ammonium polyphosphate, to the use of this powder for the layer-by-layer production of moldings, and also to moldings produced from this powder. The moldings constructed using the inventive powder have marked advantages with regard to their flammability, when comparison is made with conventional products, and this permits use in aircraft, for example.
摘要:
Moldings can be produced from a polymer powder containing at least one block polyetheramide containing an oligoamide dicarboxylic acid and a polyetheramine; wherein the powder is suitable for use in a layer-by-layer process in which regions of a powder layer are selectively melted via introduction of electromagnetic energy.
摘要:
A sintering powder containing polyamide polymer and titanium dioxide particles, a process for laser sintering, and moldings produced from the sintering powder. The moldings formed using the powder of the invention have improved surface quality due to the powders having increased yellowing resistance when exposed to thermal stress during laser sintering. Moldings produced from the sintering powder have improved mechanical properties, in particular modulus of elasticity.