| The objective of this paper is to investigate study the variation in microstructures at high temperature of TiC films deposited on the SKH9 tool steels by PECVD. We performed vacuum annealing of SKH9/TiC samples in the temperature range of 700∼1000℃, and studied on the microsturctures of TiC films by using the XRD, SEM, TEM and AES. TiC films as coated had (220) preferred orientation and it changed into (200) at 800℃ and (220) at 1000℃, respectively. The lattice parameter of TiC films decreased with vacuum annealing. At 900℃, it increased by the diffusion of carbon from the substrate into the films. At 1000℃, TiC films changed into zone 2 structure with dense columnar grains. Above 900℃, Fe and Cr diffused into TiC films and formed complex carbides of (Fe, Cr, Ti)_xC type. TiC films as coated had fine micrograins with 10∼100㎚ size. At 800℃, the growth of micrograins occurred and the size of micrograins increased to 50∼300㎚. Also at 1000℃, TiC films had very fine grain size(10∼70㎚). This is thought due to the Ac₁ transformation of substrates. |
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