中文摘要：

研究了具有Co-20Ti成分的L12-Co3Ti金属间化合物的硬度随时效时间的变化,同时测定了时效处理后含析出相的L12-Co3Ti金属间化合物的屈服强度随温度的变化.通过透射电镜观察揭示出由于析出相为单纯的面心立方结构的γ-Co相,虽然硬度低于基体的Co3Ti金属间化合物,仍然可使Co3Ti相得到有效硬化.γ-Co析出相在时效初期与Co3Ti基体保持共格关系.γ-Co析出相呈片状形态,平行于有序基体的{100}晶面析出.透射电镜观察结果表明,γ-Co析出相与变形位错的交互作用为引力型交互作用,这种引力型交互作用对材料的强化起了主要贡献.同时还讨论了由于软析出相而引起的强化机理.

英文摘要：

The variation in hardness of 80Co-20Ti intermetallic compounds with aging time was investigated, and the change in yield strength of aged 80Co-20Ti intermetallic compounds undergoing aging and containing precipitates with temperature was tested. Transmission electron microscope （TEM） observations reveal that the precipitates are γ-Co precipitates with simple fee crystal structure. Although the hardness of the precipitates is less than that of Co3Ti matrix phase, the Co3Ti hardens appreciably by fine precipitation of disordered fee Co-rich phase. The precipitates are perfectly coherent with the matrix lattice at the beginning of aging. The shape of the precipitates is platelet and is nearly parallel to the [ 100]planes of the L12-ordered matrix. It is indicated that the interaction between γ-Co precipitates and deformation dislocations is attractive interaction and this type of interaction plays an important contribution to the hardening. The strengthening mechanism deduced from the attractive interaction between the soft precipitation and hard matrix was also discussed.