| Formation behavior and characteristics of the interface which were in-situ formed between TiB₂ reactant powder and α-Ti matrix were investigated. Furthermore, the effect of a TiB growth on densification of Ti/TiB₂ mixture was also examined. Mixed powders of TiB₂ or B₄C powder with CP Ti powders were compacted and pre-sintered at 700℃ for 1 hr followed by sintering at 900, 1000. 1100, 1200. 1300℃ for 3hrs, respectively. In addition, another specimens were sintered at 1000℃ for various times in order to study the formation behavior of TiB reinforcement in-situ formed in the α-Ti matrix. TiB was formed through the different mechanisms - formation of fine TiB and formation of coarse TiB by Ostwald ripening or coalescence of fine TiB. There was no crystallographic relationship between TiB and matrix. There were voids at the interface between TiB reinforcement and α-Ti matrix because of the preferential growth of TiB without any crystallographic relationship with α-Ti matrix and the surface energy between Ti matrix and TiB reinforcements, and so densification of Ti/TiB₂ compacts was hindered by the coarse TiB growth. |
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