with a mixture of 50 ferrous silicon and 50 iron by weight fibrils were produced using optimal reactor operating parameters when using mts precursor gas there is generated significant quantities of hydrochloric acid in the off gas stream the acid destroys the vacuum system and the exhaust ducts in accordance with a further aspect of the present process the present inventor discovered that the mts liquid could be replaced with cvd4000 as the silicon carbide precursor in this embodiment the cvd4000 was reacted in nitrogen gas rather than the more dangerous hydrogen required by the mts liquid and gas silicon carbide fibrils made using the cvd4000 in nitrogen produced no acid in the offgas an unexpected advantage of the use of cvd4000 in the present invention is that fibrils grow at a temperature as low as 800 u00b0 c compared with required temperature of 1200 to 1300 u00b0 c for the mts reaction fibrils 5 to 15 u03bcm in diameter grown using the cvd4000 precursor are shown in fig7 and 8 melt growth balls were observed with the fibrils produced using cvd4000 indicating that they were vls with reference to fig1 as noted in the present process a semi continuous microware heated vacuum reactor 12 is employed as depicted in the fig1 the reactor includes a boat entry port 20 through which catalyst bearing reaction vessels 16 are introduced into a preheat chamber 22 of the reactor and wherein the reaction vessels are preheated employing resistance heat to a temperature of about 700 to 900 u00b0 c when using mts and between 501 to 800 u00b0 c when using cvd4000 the preheated reaction vessels are moved by.