B2 martensite

               

Parent phase of AuCd or TiNi. 

This crystal structure is sometimes called B2 type.  The crystal system is cubic.  It looks like body centered cubic structure, but not. 

               

g2' martensite structure.  The crystal structure is called B19, orthorhombic.  This crystal structure appears in AuCd or TiNi. 
z2' martensite structure, trigonal.  This crystal structure appears in z2' phase of AuCd or R phase of TiNi. 

Martensitic structure appeared in TiNi.  It is called B19' type structure, belonging to a monoclinic system.  

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