TC21钛合金时效析出α相的长大动力学

摘要

为研究 TC21钛合金时效时析出α相的长大动力学，采用 JMatPro 软件模拟计算得到了钛合金时效相平衡时α相和β相的化学成分与时效温度的关系，计算得到了在500~900℃下等温时效时析出α相的长大速率与温度的关系式，并进行了试验验证。结果表明：在750℃以下等温时效时，析出α相的长大速率较慢，时效温度高于800℃时，长大速率随温度升高而迅速增加，这是由合金元素的扩散系数随温度的变化而决定的；试验得到的 TC21钛合金在900℃等温时效时析出α相的长大速率与模拟计算得到的结果一致，析出α相的生长速率随温度升高不断增大。%In order to study the growth kinetics ofαphase precipitation in TC21 titanium alloy during ageing treatment,the relationship between the elemental composition ofβandαphase and aging temperature was obtained using JMatPro software.The equation between the αphase growth rate and aging temperature of 500-900 ℃ was also obtained by calculation and verified by experiment.The results show that when the aging temperature was below 750 ℃,the αphase growth rate increased slowly,while the temperature higher than 800 ℃,the growth rate increased rapidly with temperature rising,as the element diffusion coefficient increased with the aging temperature rising.The α phase growth rate obtained by observing the microstructure of TC21 titanium alloy after isothermal aged at 900 ℃ was consistent with the simulated result.Theαphase growth rate increased with the increase of aging temperature.