Pathways to Titanium Martensite
Pathways to Titanium Martensite
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DOI：
10.1007/s12666-022-02559-9
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发表时间：
2022-03
影响因子：
1.6
通讯作者：
Yufeng Zheng;R. Banerjee;Yunzhi Wang;H. Fraser;D. Banerjee
中科院分区：
文献类型：
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作者：
Yufeng Zheng;R. Banerjee;Yunzhi Wang;H. Fraser;D. Banerjee
描述了由母相β转变为马氏体时母相和产物相之间的结构关系。导致马氏体的原子运动是通过长程剪切{112}和< 111 >短波长位移或洗牌{110}来完成的，长程剪切{112}将母体转变为产物晶格，短波长位移或洗牌{110}< 110 >引起正确的堆叠。从这些路径中产生的微观结构取决于这些模式中的哪一个启动了转变。当剪切先于洗牌时，常规马氏体形成错位板条或内部孪晶板。一个签名的{110}< 110 >洗牌之后或伴随着剪切是目前在这两种情况下作为堆垛层错相关的域。随着β稳定剂添加量的增加，洗牌位移先于剪切位移，导致具有正交对称性的结构的纳米分散，我们将其指定为O′。Al、Sn、Zr和O的添加促进了洗牌。O′分散体在冷却或施加应力时作为纳米马氏体形成的胚胎。所得到的连续和受控的应变纳入晶格内的约束纳米晶胚的结果在非线性超弹性或因瓦和elinvar效应。体心立方母体的稳定性讨论的声子模式或相关的弹性常数软化。
The structural relationship between the parent and product phases in the martensitic transformation from the parent β phase is described. The atomic movements leading to the martensite are accomplished by a long-range shear {112} < 111 > that transforms the parent to the product lattice and a short-wavelength displacement or shuffle {110} < 110 > that induces the correct stacking. The microstructures arising out of these paths depend on which of these modes initiates the transformation. When the shear precedes the shuffle, conventional martensite forms as dislocated laths or internally twinned plates. A signature of the {110} < 110 > shuffle that follows or accompanies the shear is present in both cases as stacking fault-related domains. The shuffle displacement precedes the shear with increasing β stabilizer addition, resulting in a nanodispersion of a structure with orthorhombic symmetry, which we have designated as O′. Al, Sn, Zr and O additions promote the shuffle. The O′ dispersion acts as embryos for the formation of nanomartensite on cooling or with the application of stress. The resulting continuous and controlled strain incorporation into the lattice within the constrained nanoembryos results in nonlinear superelasticity or the invar and elinvar effects. The stability of the bcc parent is discussed in terms of phonon mode or related elastic constant softening.