摘要 |
Fine-grained polyether ketone powder, which has a grain size with a d50 value of less than or equal to 40 mu m and a grain size distribution range of less than or equal to 55 mu m, is obtained by cold grinding of coarse-grained polyether ketone in a fluidised-bed opposing-jet mill, which is provided with a grinding chamber (2) into which gas jets are admitted, a grinding material charging device, a sifter (5) for separating coarse material (11) and fine material (10) and a sump (3) underneath the grinding chamber for metered-in grinding material and coarse material flowing back from the sifter, the grinding material and the coarse material flowing back from the sifter being cooled by a cryogenic coolant. The powders obtained in this way are used for the preparation of surface coatings or composites. <IMAGE> |