| 摘要 |
Sintered boron carbide ceramic bodies are produced by (a) mixing boron carbide powder with an organosilicon polymer ceramic precursor (I) chosen from polysiloxanes, polysilazanes, polysilanes, metallopolysiloxanes and metallopolysilanes to form a homogeneous mixt. in which the (I) is present in such an amt. that the free carbon index of the mixt. is greater than 0.2 wt.% w.r.t. the total wt. of the boron carbide powder and the carbonisation prod. derived from the (I); (b) forming the homogeneous mixt. into the desired shape under press. and at a temp. below ca. 500 deg C to form a green body that can be further manipulated and (c) sintering the green body in an inert atmos. at a temp. above ca. 2200 deg C to form a sintered body with a density of above ca. 2.0.
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