GROWTH OF ISOTHERMAL MARTENSITE IN AN Fe-Ni-Mn ALLOY
Fe-Ni-Mn合金中等温马氏体的生长过程

The substructural development of martensite plates at different stage of the transformation for an Fe-21Ni-4Mn alloy has been investigated by using transmission electron microscope. Twinning was found in small thin platelets at the initial stage. Fine twins extend to the whole platelet. The dislocations and twins were found in the thick platelets at a later stage. Bending of the twins was also observed frequently at this stage. Finally, several platelets coalesce with each other to forma macroscopic (252)_f martensite "plate". The original habit plane of the individual platelet was measured to be close to (121)_f.