In Situ Formation of Titanium diboride/Copper Composite
Dong Shijie£¬Lei Yongping£¬Shi Yaowu
(Xi'an Jiaotong University, Xi'an 710049, China)

Abstract:  Thermodynamics and kinetics are applied to study the in situ formation of titanium diboride in Cu-B-Ti during sintering. Structural transformation of Cu-B-Ti mixed powders occurs during themechanical alloying process and sintering. A microª²mechanism model is developed for analyzing the in situ formation of titanium diboride. It can be shown that the titanium triboride phase is formed at the late stage of ball milling of Cu-B-Ti powders and at the initial stage of sintering of Cu(B, Ti) powders. With prolonged milling time, the starting temperature and the tempetature range for the formation of titanium triboride phase shift to low temperature. The formation of titanium diboride depends mainly on the diffusion and chemical reaction of the B rich phase arising from the formation of titanium triboride and the Tirich phase due to melting of titanium triboride£®
Keywords: composite;copper alloy;in situ formation;titanium diboride

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