文章信息/Info

Title:

Phase field simulation of strain glass Transition

作者:

王棟; 任曉兵; 王云志

西安交通大學(xué)，前沿科學(xué)技術(shù)研究院

Author(s):

WANG Dong;  REN Xiaobing;  WANG Yunzhi

Frontier Institute of Science and Technology, Xi’an Jiaotong Universit

關(guān)鍵詞:

馬氏體相變; 應(yīng)變玻璃轉(zhuǎn)變*; 相場動力學(xué); 相變相圖; 點(diǎn)缺陷

DOI:

10.7502/j.issn.1674-3962.2016.06.02

文獻(xiàn)標(biāo)志碼:

A

摘要:

應(yīng)變玻璃轉(zhuǎn)變是在形狀記憶合金中最新發(fā)現(xiàn)的一種玻璃化轉(zhuǎn)變過程，這種玻璃化轉(zhuǎn)變過程有著不同于正常馬氏體轉(zhuǎn)變的一些特性。本文通過引入缺陷改變形狀記憶合金的平均馬氏體相的熱穩(wěn)定性和缺陷產(chǎn)生的局部畸變場這兩種缺陷的效應(yīng)建立了新的朗道勢能—缺陷模型。通過相場動力學(xué)的模擬，成功的預(yù)測了實(shí)驗(yàn)發(fā)現(xiàn)的應(yīng)變玻璃轉(zhuǎn)變現(xiàn)象及相關(guān)的奇異性質(zhì)。另外，通過相場模擬結(jié)果建立了與實(shí)驗(yàn)一致的完整的模擬相變相圖，成功的描述了形狀記憶合金中除了正常奧氏體態(tài)和馬氏體態(tài)之外的奇異應(yīng)變態(tài)，理論模擬為理解這些應(yīng)變態(tài)及其之間的相關(guān)性提供了基礎(chǔ)。通過耦合應(yīng)變玻璃模型和外加力場，模擬了應(yīng)變玻璃轉(zhuǎn)變的奇異力學(xué)特性；其中包括窄的應(yīng)力應(yīng)變遲滯回線，應(yīng)變玻璃成分的應(yīng)力—溫度相變相圖，以及在不同的加載情況下，體系在升降溫過程中的熱滯后性能。本文研究工作為進(jìn)一步通過模擬來指導(dǎo)和設(shè)計(jì)新型可應(yīng)用的應(yīng)變玻璃態(tài)材料打下了基礎(chǔ)。

Abstract:

Strain glass transition was recently discovered in shape memory alloys and show typical glass transition characteristic 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 rich the field of glass materials or disorder materials, but also open new application potential and promote 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 is introduced. Through the phase field dynamics simulation, the experimental results reported strain glass transition phenomenon and the related properties are 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 suggest a way to guide the design and development of new shape memory alloys through the application of strain glass transition.