利用TEM及HREM研究了9Ni钢中马氏体与渗碳体的取向关系和相界结构观察表明多数马氏体与渗碳体之间满足Bagaryaskii关系，但也有例外观察到一种和已知的三种取向关系不同的情况：（110）θ／／（110）α；[111]θ／／[111]α棒状渗碳体与马氏体界面上存在台阶．颗粒状渗碳体和马氏体相界间存在失配位错 TEM and HREM were used to study the orientation relationship between martensite and cementite in 9Ni steel and the observation of the phase boundary structure showed that most of the martensite and cementite meet the Bagaryaskii relationship but there were also some exceptions and observed The three orientations are different: (110) θ // (110) α; [111] θ // [111] α There is a step on the interface between the rod-shaped cementite and the cementite. Miscible dislocations exist between the granular cementite and the martensite interface