摘要
应用TEM对Ti 56Al单晶 [1 0 3]有序畴区位错结构进行研究 ,并提出修正的钉扎 -解钉模型以解释 1 /2 <1 1 0 ]普通位错不是长而直的纯螺位错及位错碎片不是沿纯螺方向排列等实验现象和反常屈服机制。认为 ,当TiAl合金中的Al含量较低时 ,1 /2 <1 1 0 ]普通位错控制的反常屈服行为可用Viguier的钉扎 -解钉模型解释 ;当TiAl合金中的Al含量较高时 ,1 /2 <1 1 0 ]普通位错控制的反常屈服行为可用本文提出的修正的钉扎 -解钉模型解释。
The dislocation struct ure in [103]ordered domain of Ti 56Al single crys tal was investigated by using transmissi on electron microscopy(TEM).A modified pinning unpinning model was presented to explain the mechanism of anomalous yiel d and the experimental phenomena that 1/ 2 [110] ordinary dislocations were not l ong and straight screw dislocations,and the dislocation debris did not tend to a lign along with the screw orientation.It was thought that the anomalous yield behavi or controlled by 1/2 [110] ordinary disl ocation could be explained by means of t he pinning unpinning mechanism suggested by Virguier when the TiAl alloy contain ing lower Al amount,but by this modified pinning unpinning mechanism when TiAl a lloy contained a higher Al amount.
出处
《上海金属》
CAS
2001年第3期10-15,共6页
Shanghai Metals
基金
国家自然科学基金资助项目
