摘要
用透射电镜,X 射线衍射技术研究了 Ti-Al-Nd 合金中稀土 Nd 的存在形态及其对 Ti_3X 析出的影响。结果表明,Nd 主要以脱氧产物 Nd_2O_3的颗粒弥散分布于基体中,颗粒尺寸约为100-200nm,Nd_2O_3为 bcc 结构。稀土 Nd 对合金的强化作用主要是 Nd_2O_3颗粒与位错作用引起的强化及 Nd_2O_3周围形成的位错亚结构的强化。Nd 对 Ti_3X 相析出有较好的抑制作用,其机理是稀土 Nd 的脱氧反应促使基体中氧的贫化,从而降低了合金的平均电子浓度所致。
The existance form of RE element Nd and its effect on the precipitation ofTi_3X phase in Ti-Al-Nd alloy were investigated by TEM and X-ray diffraction techniques.The results show that the existance form of RE element Nd in Ti alloy is mainlyNd_2O_3 particles,which is the product of internal oxidation during melting and casting.The re-sults also show that the size of Nd_2O_3 particles is about 100-200nm and its structure is bcc.Thestrengthening role of Nd in titanium alloy is the combined interaction of Nd_2O_3 particles withdislocations.The depression effect of Nd on the Ti_3X phase formation is attributed to its low-ering the oxgyen concentration by internal oxidation and then lowing the average electron con-centration.
基金
国家自然科学基金
5870013
关键词
钛合金
稀土元素
ND
Ti3X相
Rare-earth element
Ti_3X phase
particles strengthening
