应变玻璃转变是在形状记忆合金中发现的一种玻璃化转变过程，这种玻璃化转变过程有着不同于正常马氏体转变的一些特性。通过引入缺陷进而改变形状记忆合金的平均马氏体相的热稳定性和缺陷产生的局部畸变场这两种缺陷的效应，作者课题组建立了新的朗道势能—缺陷模型。通过相场动力学的模拟，成功地预测了实验发现的应变玻璃转变现象及相关的奇异性质。另外，通过相场模拟结果建立了与实验一致的、完整的模拟相变相图，成功地描述了形状记忆合金中除了正常奥氏体态和马氏体态之外的奇异应变态，理论模拟为理解这些应变态及其之间的相关性提供了基础。通过耦合应变玻璃模型和外加力场，模拟了应变玻璃转变的奇异力学特性；其中包括窄的应力应变迟滞回线，应变玻璃成分的应力－温度相变相图，以及在不同的加载情况下，体系在升降温过程中的热滞后性能。本研究工作为进一步通过模拟来指导和设计新型可应用的应变玻璃态材料打下了基础。%Strain glass transition was recently discovered in shape memory alloys and showed typical glass transition char⁃acteristic and abnormal properties from that of normal martensitic transition. Special applications were found based on the abnormal “strain glass” state, such as shape memory, superelasticity and good internal friction. The discovery of strain glass transition not only riches the field of glass materials or disorder materials, but also opens new application potential and promotes the finding and study of abnormal strain states in shape memory alloys. In this paper, the effect of defects on the thermal stability of martensite and the local distortion in the shape memory alloy were introduced. Through the phase field dynamics simulation, the experimental results reported strain glass transition phenomenon and the related properties were successfully predicted. Phase field simulations establish the full transformation phase diagram which is consistent with the experimental results. The phase field simulations provide a basis for understanding the origin of strain glass. Through the coupling of strain glass model and external field, this paper simulated the abnormal mechanical properties of strain glass transition, including narrow stress strain hysteresis loops, thermal hysteresis and temperature⁃stress phase diagram in strain glass composition. This work suggested a way to guide the design and development of new shape memory alloys through the application of strain glass transition.
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