Fe-30 wt% TiC composite powders are fabricated by in situ reaction synthesis after planetary ball milling of (Fe, TiH2, Carbon) powder mixture. Two sintering methods of a pressureless sintering and a spark-plasma sintering are tested to densify the Fe-30 wt% TiC composite powder compacts. Pressureless sintering is performed at 1100, 1200 and 1300°C for 1-3 hours in a tube furnace under flowing argon gas atmosphere. Spark-plasma sintering is carried out under the following condition: sintering temperature of 1050°C, soaking time of 10 min, sintering pressure of 50 MPa, heating rate of 50°C/min, and in a vacuum of 0.1 Pa. The curves of shrinkage and its derivative (shrinkage rate) are obtained from the data stored automatically during sintering process. The densification behaviors are investigated from the observation of fracture surface and cross-section of the sintered compacts. The pressureless-sintered powder compacts are not densified even after sintering at 1300°C for 3 h, which shows a relative denstiy of 66.9%. Spark-plasma sintering at 1050°C for 10 min exhibits nearly full densification of 99.6% relative density under the sintering pressure of 50 MPa.
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