| Martensite transformation crystallography is mainly focused on the study of cyrstallograhic features between the matrix and the precipitates of a material which undergoes martensite transformation. It includes the orientation relationships (ORs), the habit planes (HP) and the interfacial structures as well as the dislocation type, the dislocation line and the spacing of dislocations. In this dissertation, the recent transformation crystallographic models are generalized, and the basic principles of each model are introduced, moreover, their advantages and disadvantage are compared. The Edge-to-edge model and O-lattice model, combined with theΔg parallel rule have been applied to predict the crystallographic features of HCP/FCC and FCC/BCC system for a given lattice parameter ratio. This work provides theoretical foundation and practical methods for the further research into the martensite/residual austensite and bainite/residual austensite interface structures. The primary results of the present work are as follows:(1) By adoption of the Edge-to-edge matching model, the possible orientation relationship with different range of a H /aF and cH /aH was predicted. Among them the most possible matching direction was the closest packed [1120]H //[110]F direction with the lowest misfit degree. This agrees with the general knowledge of materials science.(2) The orientation relationships between theγaustensite (FCC) and the precipitateε-martensite (BCC) in Fe-30Mn-6Si shape memory alloy were predicted to be [1120]H //[110]F and(0002) H //(111) F, which agreed well with the experimental results.(3) The ORs and the corresponding crystallographic features in martensite/austensite and bainite/austensite systems was carefully calculated and compared by using the O-line analytical method.(4) The variation of the crystallographic features in several OR types with the lattice parameter ratios was analyzed.
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