But the tetragonal phase in the surface region transforms easily to monoclinic phase when the samples are exposed to air.
尽管惰性气氛和还原气氛下焙烧样品有利于四方相的稳定，但样品暴露于空气中后，表面四方相较易转变为单斜相。
It is found that the increase of oxygen vacancy content can increase the instability of the metastable tetragonal phase and accelerate the transformation to monoclinic zirconia.
结果表明：氧空位的存在与变化不仅影响着氧化锆相结构的稳定性，而且影响着氧化锆的低温相变过程。
Titanium nitride was synthesized by ammonia reduction and nitridation under flowing ammonia atmosphere while the content and tetragonal phase structure of zirconia was unchanged.
采用氨气还原氮化法，在流动的氨气氛下原位反应生成氮化钛，同时保持四方相氧化锆含量和结构不变。
The results show that the content of tetragonal phase is increasing in BNBT ceramics by direct reaction sintering method but still exhibiting a single phase of perovskite structure.
结果表明，直接反应烧结法不影响BNBT陶瓷的钙钛矿相结构，但可使准同型相界处组成的四方相含量增加；
These disadvantages cannot be overcome by addition of tetragonal zirconia resulting in phase transition toughening, because of the low elastic module of the ceramic artificial bone materials.
由于生物陶瓷材料的弹性模量较小，很难采用添加氧化锆引起的相变增韧来解决上述缺点。
The major phase constituent obviously transforms from cubic paraelectric phase to tetragonal ferroelectric phase after sintering, in which the ferroelectric domains exist.
烧结前后陶瓷相结构明显改变，由原来的立方顺电相为主转变为四方铁电相为主，并存在铁电畴亚结构；
It is possible that oxygen vacancies formed in the surface region in the absence of oxygen can prevent the transformation from the tetragonal to the monoclinic phase.
这可能是由于在缺氧条件下样品表面形成了一种具有氧空位的扭曲结构，这种结构可以阻止四方相到单斜相的转变。
We also study the relation between the dielectric constant and lattice distortion of the PT tetragonal and cubic phase region.
我们还研究了PT四方相区和立方相区介电常数与晶格畸变的关系。
When the sample is exposed to air, the elimination of these vacancies by the incorporation of oxygen facilitates the transformation from the tetragonal to the monoclinic phase.
当暴露于空气中时，表面氧空位能够捕获空气中的氧，有利于表面四方相转变为单斜相。
We comprehensively investigate and discuss the relation in the tetragonal, rhombohedral and coexistence phase region of PZT.
我们对PZT四方相区、三角相区和混合相区介电常数与晶格畸变的关系进行了全面研究和探讨。
The results indicate that the coating is mainly composed of tetragonal and cubic phase and a small amount of monoclinic zirconia.
结果表明，涂层主要以四方相和立方相构成，并含有少量的单斜相。
The results of XRD and SEM show that the main crystal phase is the non-full-filled tetragonal tungsten bronze structure.
SEM结构分析可知，主晶相为非填满型钨青铜结构四方晶相。
X-ray Diffraction(XRD)was applied to study crystalline properties of PLT films, and XRD patterns of PLT thin films show that there appeared(111)preferred-oriented tetragonal perovskite phase.
用X射线衍射技术（XRD）研究了PLT薄膜结晶性能，结果表明PLT薄膜为（111）择优取向钙钛矿相织构。
X-ray Diffraction(XRD)was applied to study crystalline properties of PLT films, and XRD patterns of PLT thin films show that there appeared(111)preferred-oriented tetragonal perovskite phase.
用X射线衍射技术（XRD）研究了PLT薄膜结晶性能，结果表明PLT薄膜为（111）择优取向钙钛矿相织构。
应用推荐