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TiAl based alloy with excellent high temperature performance , study the TiAl alloy sheet preparation method has very important theoretical and practical value . In this paper, the boron carbide particles reinforced aluminum matrix composite plate (B 4 Cp / Al) and titanium (Ti) plates as raw material multilayer Ti -B 4 sub > Cp / Al plate pack rolling and heat treatment . By means of SEM, XRD and other studies of the phase composition of the reaction layer in the heat treatment process , reaction thermodynamics and kinetics . Were prepared by powder metallurgy method 5vol % 10vol % and 15vol % B . 4 < / sub> Cp / Al composites . Compare Ti and B 4 Cp / Al hot compression deformation rate , determine the multi-layer Ti-(5% B 4 Cp / Al) plate pressing and hot The rolling temperature are 500 ℃. After 80% of the amount of pressure rolling , Ti plate and B 4 < / sub > Cp / Al plates basically reached the deformation coordination . After 650 ° C low temperature heat treatment , the multilayer Ti -B 4 sub > Cp / Al plate reaction layer uniform of TiAl 3 sub > phase, there is a small amount of unreacted Ti and Al . Low-temperature heat treatment , 50 hours after 650 ℃ for multilayer Ti - ( B 4 < / sub > Cp / Al ) plate into a multilayer Ti -TiAl 3 < / sub > - ( B - Cp / Al) plate . Multilayer Ti-TiAl 3 - (B 4 Cp / Al) board in the high - temperature heat treatment process , the reaction layer , incubated at 950 ℃ Ti 3 sub > Al, TiAl, TiAl 2 , TiAl 3 phase composition , and there is a large composition gradient ; 1100 ℃ for each phase gradually transformed into Ti 3 Al, TiAl, TiAl 2 , the composition gradient decreases. High-temperature heat treatment after 1100 ℃ for 40 hours , multilayered Ti -TiAl 3 sub > - ( B 4 < / sub > Cp / Al ) plate into Ti 3 Al - TiAl -TiAl 2 sub > - ( the B 4 Cp / Al ) gradient plate . By studying the heat treatment kinetics obtained multilayer Ti -( B 4 < / sub> Cp / Al ) plate heat treatment the growth mechanism of the reaction layer is parabolic growth kinetics of the reaction-diffusion mechanism , control and get a multi-layer Ti-(B 4 Cp / Al) board the kinetic equation of the high-temperature heat treatment .
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