Measurement of the lattice plane strain and phase fraction evolution during heating and cooling in shape memory NiTi
Measurement of the lattice plane strain and phase fraction evolution during heating and cooling in shape memory NiTi
复制标题
DOI：
10.1063/1.3245308
复制
发表时间：
2009-10
影响因子：
4
通讯作者：
S. Qiu;V. Krishnan;S. Padula;R. Noebe;D. Brown;B. Clausen;R. Vaidyanathan
中科院分区：
文献类型：
--
作者：
S. Qiu;V. Krishnan;S. Padula;R. Noebe;D. Brown;B. Clausen;R. Vaidyanathan
我们报告在原位中子衍射测量加热和冷却过程中通过形状记忆NiTi的相变。晶格面比应变随温度的变化保持线性关系，不受晶间应力的影响，从而确定了B19′ NiTi的热膨胀张量。的中子测量是一致的，与宏观衍射测量和30 000晶粒多晶自洽模型。B19′ NiTi的相变性质导致宏观形状变化从转变的开始和结束被抵消（随温度）。在没有偏置应力的情况下，织构不会演变。
We report on in situ neutron diffraction measurements during heating and cooling through the phase transformation in shape memory NiTi. The lattice plane specific strain evolution remains linear with temperature and is not influenced by intergranular stresses, enabling the determination of the thermal expansion tensor of B19′ NiTi. The neutron measurements are consistent with macroscopic dilatometric measurements and a 30 000 grain polycrystalline self-consistent model. The accommodative nature of B19′ NiTi results in macroscopic shape changes being offset (with temperature) from the start and finish of the transformation. The texture does not evolve in the absence of biasing stresses.