【摘要】 本文通过三维相场模型,模拟了孪晶结构马氏体的生长,计算了马氏体生长过程中的能量变化.结果表明,在马氏体变体长大阶段,随演变时间的延长,对于2个变体马氏体组成的体系,其总弹性应变能增加;而对于3个马氏体变体组成的体系,其总弹性应变能降低.本文的相场模拟揭示了3个马氏体变体具有最佳的的应变自协调效应.更多还原

【Abstract】 The number of martensitic variants depends on the grain size and orientation of parent phase.Although the growth of polytwin structure with the combination of different martensitic variants was studied by in situ dynamic observation,the energy change during the growth of martensite cannot be revealed,and in turn the strain self-accommodation of martensitic transformation(MT)cannot be confirmed.Based on the recent study of the phase field model,describing proper martensitic transformation for a single-crystal system under a fully constrained boundary,a three-dimensional (3D)phase field simulation is performed to demonstrate the microstructure evolution of plolytwin structure in this paper,meanwhile,the energy change during the growth of martensite is calculated. The results indicate that during the growth of two martensitic variants the total strain energy increases with prolonging microstructural evolution time,however,the opposite change occurs during the growth of three martensite variants.The 3D phase field simulation reveals that the growth of three martensitic variants possesses the best strain self-accommodation effect.更多还原