【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 Ti₃X 析出的影响。结果表明,Nd 主要以脱氧产物 Nd₂O₃的颗粒弥散分布于基体中,颗粒尺寸约为100-200nm,Nd₂O₃为 bcc 结构。稀土 Nd 对合金的强化作用主要是 Nd₂O₃颗粒与位错作用引起的强化及 Nd₂O₃周围形成的位错亚结构的强化。Nd 对 Ti₃X 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。更多还原

【Abstract】 The existance form of RE element Nd and its effect on the precipitation ofTi₃X 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 mainlyNd₂O₃ particles,which is the product of internal oxidation during melting and casting.The re-sults also show that the size of Nd₂O₃ particles is about 100-200nm and its structure is bcc.Thestrengthening role of Nd in titanium alloy is the combined interaction of Nd₂O₃ particles withdislocations.The depression effect of Nd on the Ti₃X phase formation is attributed to its low-ering the oxgyen concentration by internal oxidation and then lowing the average electron con-centration.更多还原