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 invention relates to powder, comprising composite particles comprising core particles completely or partially coated with a precipitated first polymer, where the core particles comprise a second polymer which differs from the precipitated first polymer, and where the ratio of the d50 median diameter of the composite particles to the d50 median diameter of the core particles is 1.15 or greater. The invention further relates to processes of using the powders of the present invention to making mouldings.
摘要:
A pulverulent composition that is a powder containing at least one polymer, and at least one flame retardant that contains ammonium polyphosphate, the powder having a maximum particle size of ≦150 μm and a median particle size of from 20 to 100 μm.
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:
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:
Composite particles comprising core particles completely or partially coated with a precipitated polymer, where the d50 median diameter of the core particles is 1 μm or greater and the ratio of the d50 median diameter of the composite particles to the d50 median diameter of the core particles is 1.15 or greater, are provided. A method to prepare the particles includes dissolution of a polymer in a solvent and reprecipitation 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:
A molding produced by a layer-by layer process of selectively melting regions of a respective pulverulent layer via unfocused introduction of electromagnetic energy, using a polymer powder, where the powder has at least one thermoplastic random copolymer with an ISO 1133 MFR value of from 12 to 1 g/10 min.
摘要:
A sinter powder containing a polyamide and metal soaps, in particular particles of a salt of an alkanemonocarboxylic acid. A process for laser sintering, and to moldings produced from the sinter powder. The moldings formed using the powder have advantages in appearance and in surface finish when recyclability in the selective laser sintering (SLS) process is taken into account. Moldings produced from recycled sinter powder have improved mechanical properties, in particular in the modulus of elasticity and tensile strain at break.
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 3 to 100 μm and wherein the glass core particle material is at least one selected from the group consisting of a solid glass bead, a hollow glass bead, a porous glass bead, and a foamed glass particle. 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 glass particles. Further provided is a layer by layer moulding process employing the composite particles and mouldings obtained therefrom.