摘要
用(EHT)紧束缚能带计算方法计算了g -TiAl及其掺杂合金的原子间成键强度,并依据键强度建立了判断掺杂原子取代位置的模型。掺杂原子的位置应根据取代前后的键强度相近的取代方式进行确定。模型预测的结果与场理论方法的结果是一致的,也与实验结果基本相符,据此能够定性判断掺杂原子的取代位置。
The bonding (overlap populations) between atoms in g -TiAl and its substitute alloys has been calculated by EHT band method, and a model was proposed to judge the site occupation of ternary element substitution by means of the bonding intensity. It is concluded that the sites of doping atoms should be determined according to the manner which can give closer bonding intensity before and after the substitution.The result of the model prediction is consistent with the field theory method, and also with the experimental observations.