| 摘要 |
The invention relates to a process for the manufacture of an aluminium nitride ceramic body having a composition defined and enclosed by the polygon FJDSR, but not including the line RF, of Figure 4, and having a porosity of less than 10 per cent by volume and a thermal conductivity greater than 1.00 W/cm.K at 25 DEG C, in which a mixture consisting of oxygen-containing aluminium nitride powder, yttrium oxide and free carbon is prepared, the mixture is moulded to give a pressing, the mixture and the pressing having a composition in which the equivalent percentages of yttrium and aluminium lie between point D and point F in Figure 4 and the pressing having an equivalent percentage composition of Y, Al, O and N outside the composition as defined and enclosed by the polygon FJDSR of Figure 4, the pressing is heated to a temperature at which its pores remain open, the free carbon is reacted with the oxygen contained in the aluminium nitride and a deoxidised pressing is produced, the deoxidised pressing having a composition in which the equivalent percentages of Al, Y, O and N are defined and enclosed by the polygon FJDSR, but not including the line RF, of Figure 4, and the deoxidised pressing is sintered at a temperature of at least about 1840 DEG C to form the ceramic body. <IMAGE>
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