摘要 |
A process is disclosed for producing wax microspheres from molten wax. Hot water or other motive liquid in which molten wax is immiscible, is flowed under pressure through an orifice zone into which the molten wax is drawn to form a dispersion of molten wax. The dispersion is discharged into a liquid in which the wax is also immiscible, so that the wax solidifies. The liquid is maintained at a controlled temperature below the melting point of the wax. Essentially spherical wax microspheres are formed in the size range from 1 mu to about 350 mu in a two-tier weight distribution. A mass of these wax microspheres are recovered from the surface of the liquid, and dried to yield a mass of free-flowing individual wax microspheres which are used to produce a sintered porous body having a void fraction in the range from about 0.1 to 0.5. Enough smaller microspheres are lodged in the interstitial spaces between larger microspheres, resulting in a densified powder; the densified powder, in turn, when sintered, is further "autogenously" densified, forming a denser sintered body than is formed with wax powder of uniform microspheres of either the larger size only, or the smaller size only, when either of such uniform sizes are sintered by the requisite amount of laser energy.
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