Sintering Rates in the Selective Laser Sintering Process

This paper presents. a procedure to determine rates of sintering as a function of temperature using an isothermaloven. The rate of height change of a powder sample in the oven at temperatures near the Tg or Tm is measured. From this information an activation energy is calculated. This activation energy is similar to activation energies calculated from viscosity versus ternp.erature curves for polymer melts. This similarity suggests that viscous sint~ring models such. as those by Frenkel and Scherer are appropriate. A comparison between sintering rates of polymer coated alumina powder and mixed powders of the polymer with alumina, suggest that better sintered products may result from the coated powders than from simple mixtures.