| 摘要 |
A powder mixture comprising 5 to 20% of polytetrafluoroethylene with a particle size less than 2 microns and 95 to 80% of a filler such as iron powder of particle size less than 20 microns is mixed with a high boiling silicone based oil and a heat resistant silicone based varnished, compacted or extruded and sintered in air, preferably above 650 DEG C. The iron powder may by phosphated and a wetting agent such as methyl ethyl ketone and a lubricant such as naphtha may be added to the mixture.ALSO:A mixture comprising by weight 5% to 20% polytetrafluoroethylene with a particle size less than 2 microns, 95% to 80% of a filler such as iron powder with a particle size less than 20 microns, a high boiling silicone based oil and a heat resistant silicone based varnish is sintered, preferably above 650 DEG C. to form an article with improved electrical properties. The iron powder may be phosphated and a wetting agent such as methyl ethyl ketone and a lubricant such as naphtha may be added to the mixture which is extruded or compacted and sintered in air. The varnish may be incorporated by coating the dried extruded mixture and the oil may be impregnated into the compacted mixture. |
