Texture and Microstructure of Ti-Ni Melt-Spun Shape Memory Alloy Ribbons
Texture and Microstructure of Ti-Ni Melt-Spun Shape Memory Alloy Ribbons
复制标题
钛镍熔纺形状记忆合金带的织构与显微结构
DOI：
10.2320/matertrans.45.214
复制
发表时间：
2004
影响因子：
1.2
通讯作者：
S. Miyazaki
中科院分区：
文献类型：
--
作者：
A. Khantachawana;H. Mizubayashi;S. Miyazaki
采用快淬法制备了Ni含量分别为49.0at%、50.0at%和51.0at%的Ti-Ni薄带，研究了薄带的形状记忆行为、织构和显微组织。通过X射线衍射极图确定了母相B2的织构。一个强大的h100 i纤维织构被发现在极图和取向分布函数（ODF）。TEM观察表明，所有条带均完全晶化，在B2相的{100}面上均匀分布着长约10 nm的盘状析出相。Ti-49.0 at%Ni和Ti-50.0 at%Ni两种薄带在不同恒定应力下的热循环试验表明，形变回复应变超过5%，塑性变形临界应力高于400 MPa。快淬薄带的这些优异的形状记忆特性是由于这些盘状析出物的形成。此外，在Ti-51.0 at%Ni的快淬薄带中，沿晶界沿着出现了直径约为25 nm的Ti 2 Ni沉淀相。由于基体中的Ni含量由于Ti 2Ni沉淀物的形成而被冷凝，因此在实验条件下在Ti-51.0 at%Ni的初生薄带中没有观察到形状记忆效应。
The shape memory behavior, texture and microstructure were studied for Ti-Ni ribbons fabricated by a melt-spinning method where the Ni contents were designed to be 49.0 at%, 50.0 at% and 51.0 at%. The texture of the parent B2 phase was determined by X-ray diffraction pole figures. A strong h100i fiber texture was found in both pole figures and orientation distribution functions (ODF). TEM observation revealed that all the ribbons are fully crystallized and that disk-type precipitates of about 10 nm in length locate on {100} of B2 phase uniformly. The thermal cyclic tests under various constant stresses showed shape recoverable strains exceeding 5% and critical stresses for plastic deformation being higher than 400 MPa for Ti-49.0 at%Ni and Ti-50.0 at%Ni as-spun ribbons. These excellent shape memory characteristics of the melt-spun ribbons are due to the formation of these disk-type precipitates. In addition, Ti2Ni precipitates of 25 nm in diameter appeared along grain boundaries of Ti-51.0 at%Ni as-spun ribbon. Since the Ni content of the matrix is condensed due to the formation of Ti2Ni precipitates, no shape memory effect was observed in Ti-51.0 at%Ni as-spun ribbon under the experimental conditions.