Abstract: Useful thermoplastic polymer powders are formed by a method comprising: cooling a foam comprised of a thermoplastic foam below the brittleness temperature of the thermoplastic polymer, wherein the foam has an average strut dimension of 10 to 500 micrometers, and comminuting the cooled foam to form a thermoplastic polymer powder. The method allows for the efficient grinding of the thermoplastic polymer having improved morphology and desirable characteristics such as dry flow without flow aids.

Abstract: Useful thermoplastic polymer powders are formed by a method comprising: cooling a foam comprised of a thermoplastic foam below the brittleness temperature of the thermoplastic polymer, wherein the foam has an average strut dimension of 10 to 500 micrometers, and comminuting the cooled foam to form a thermoplastic polymer powder. The method allows for the efficient grinding of the thermoplastic polymer having improved morphology and desirable characteristics such as dry flow without flow aids.

Abstract: In one instance a semicrystalline polyketone powder useful for additive manufacturing is comprised of a bimodal melt peak determined by an initial differential scanning calorimetry (DSC) scan at 20° C./min and a D90 particle size of at most 300 micrometers and average particle size of 1 micrometer to 150 micrometers equivalent spherical diameter. In another instance, A composition is comprised of a semicrystalline polyketone powder having a melt peak and a recrystallization peak, wherein the melt peak and recrystallization peak fail to overlap.

Abstract: A semicrystalline polyketone powder useful for additive manufacturing may be made by dissolving a polyketone having differential scanning calorimetry (DSC) monomodal melt peak, at a temperature above 50° C. to below the melt temperature of the polyketone, precipitating the dissolved polyketone by cooling, addition of a nonsolvent or combination thereof. The method may be used to form polyketones having a DSC melt peak with an enthalpy greater than the starting polyketone.

Abstract: An example apparatus for producing a part from a powder using a powder sintering process can include a build chamber including one or more walls and a build piston configured to support the powder and the part. Additionally, the build chamber can enclose a build cylinder and a build surface, and the build piston can be arranged at least partially within the build cylinder. The apparatus can also include a plurality of heat sources distributed in the walls of the build chamber, the build cylinder and/or the build piston, an energy source arranged outside of the build chamber and configured to produce and direct an energy beam to the build surface, and a controller configured to control the heat sources.