形核率

Nb、Zr复合添加可以明显促进非晶相形成，提高软、硬磁相的晶化温度，提高形核率，细化晶粒。

The combined Nb and Zr additions can promote forming amorphous phases , and increase crystallizing temperature and nucleation rate and thus refine grains .

表面活性元素Sr在凝固过程中富集于固液界面前沿，从而增大了实际过冷度，提高了形核率，阻碍了晶粒的生长。

The surface active element Sr enriched on the solid / liquid interface in the processing of solidification . This will reduce the latent heat and increase the undercooling , and so increase the nucleation rate , thereby block the growth of the grain .

Li显著地降低了铝液表面张力，大大提高了异质形核率和形核速率，是细晶层产生的必要条件；

Li reduces the surface tension of aluminum luquid obviously , increases the ratio and rate of heterogeneous nucleation , which is the necessary condition of the formation of fine grains .

MPCVD金刚石薄膜形核率研究

The Rate of Nuclear Formation of Diamond Film by MPCVD Method

溶液浓度则是通过形核率来控制临界晶核尺寸和晶粒长大。

Solution concentration controlled critical crystal size and crystal increasing .

对压力下结晶形核率的理论计算

An expression for nucleation rate of crystallization under pressure

分析了不经划痕处理的基材形核率低的原因。

The reason why the nucleation rate is slow on the unscratched surface is discussed .

定量观察表明高的形核率是纳米准晶形成的原因。

The formation of nano quasicrystals is attributed to the high nucleation density and nucleation rate .

确定了超过冷条件下晶体组织的骤然细化起因于大过冷度下的高形核率。

The sudden refinement of crystal structure is determined by the high nucleation rate under large undercooling .

由此发现脉冲电流对金属凝固组织的细化作用是极大地提高了金属的形核率。

These verify that refining effect of ECP on structure of metal is promoting the nucleation rate .

且随着温度的升高，其成核速率不断降低，最终趋向于零形核率。

The increasing of the crystallization leads to the reduce of nucleation rate , ultimately to zero .

阐述了挤压铸造比压对形核率及成长线速度的影响。

Effects of the specific pressure on nucleation rate and linear growth velocity were expounded in squeeze casting .

通过形核率的计算进一步分析了三个共晶相之间的竞争形核机制。

By means of calculating nucleation rates , the competitive nucleation among the three eutectic phases is analyzed .

针对不同类型的球墨铸铁的凝固过程，建立了亚共晶、共晶和过共晶球墨铸铁的形核率计算模型。

The nucleation model of the hypoeutectic , eutectic and hypereutectic spheroidal graphite iron is developed considered with their solidification process respectively .

结果表明，弯折压平交替变形后，随热处理温度的升高，再结晶形核率增加。

The results show that after alternate deformation , with the increase of heat treatment temperature , the nucleation ratio of recrystallization rises .

采用定量金相分析技术和冷却曲线热分析法，定量的研究了不同碳当量、孕育量和冷却速度的球墨铸铁件的石墨球的形核率。

The graphite nucleation density of the spheroidal graphite iron is studied with samples which has different carbon equivalent , inoculation and cooling rate .

结果表明，超高冷却速率使过冷度变大，形核率升高，新相形核主要以晶内形核为主。

It was demonstrated that condensate depression and nucleation rate increase with increasing cooling velocity and intracrystalline nucleation is main nucleation form of the new phase .

在观测和计算的基础上，对微空洞的形核率和长大率与塑性应变的关系进行了分析和讨论。

Based on these observations and computations , some analytical results have been made to show strain dependency of voids nucleation rate and voids growth rate .

而对于大直径试样，包晶相所占体积分数以及形核率的不同将导致形成离散带状、岛屿带状和耦合生长组织。

But to the big sample , the differences of the volume fraction of peritectic phase and the nucleation rate cause to form the discrete band , island band and coupled-growth structures .

复合电刷镀过程中纳米颗粒的作用及脉冲换向电流，能进一步提高镀层的形核率及抑制晶粒的生长，从而减小纳米晶的尺寸。

In composite brush plating process , the existence of nano particles and pulse reverse current increase the nucleation rate and restrain the grain growth , which results in the refinement of nanocrystalline .

建立了模拟多晶金属材料动态再结晶过程的二维元胞自动机模型，模型考虑了动态回复、位错密度及形核率等因素对动态再结晶的影响。

A two-dimensional cellular automaton model was developed to simulate dynamic recrystallization process of polycrystalline metals . The model considered the effects of dynamic recovery , dislocation density and nucleation rate on dynamic recrystallization .

表面超细组织是因为撞击应变、快速加热等效应变、快速加热和冷却形核率提高及位错和空位的增加联合作用引起的。

Extra-fine-structure resulted from comprehensive factors , such as bumping strain , fast heating equivalence strain , increase of new phase nucleation rate owing to high speed heating and cooling , increase of dislocations and vacancies .

等温内耗的变化规律可根据相变理论和局部软化理论，通过孕育期内形核率J~的变化作出解释。

Based upon the theory of phase transformation and the theory of local softening mode , a rule of the change in isothermal internal friction can be interpreted through the change of the nucleation rate within the incubation period .

当粒子直径较大时，晶体生长方向性很强，形成柱状晶组织；当粒子直径较小时，熔体形核率高，凝固组织以均匀细小的等轴晶为特征。

Crystal growth exhibits apparent growth orientation and forms columnar crystallites , while particle diameter is large . With the decrease of particle diameter , the nucleation increases , the microstructure is characterized by uniform and fine equiaxed crystallites .

与未施加脉冲电流相比，晶粒得到细化、等轴化。脉冲电流作用下剧烈的强迫对流促进晶粒从型壁上游离，增加金属熔体的形核率，晶粒得到细化。

Comparing with the solidified sample in the absence of pulse electric current , the grain is refined and equiaxed with pulse electric current because compelling convection can promote the grain dissociate from mold wall , and increase nucleation rate .

本文建立了电流密度与渗碳体分解速率和石墨形核率的理论关系式，表明脉冲电流密度增加，渗碳体的石墨化进程加快。

In the paper , the theoretical relationship between the dissolution rate of cementite , nucleation rate of graphite and the pulse current density was established . With the increase of pulse current density , the graphitization of cementite was accelerated .

对再结晶动力学的理论研究表明，脉冲电流提高再结晶形核率，降低再结晶核心的长大速度。首次建立了脉冲电流作用下的再结晶动力学方程。

The theoretical studies on recrystallization kinetics suggested that current pulses increase the rate of recrystallization nucleation and decrease the growth rate of recrystallized nucleus , upon which , the kinetics equation for recrystallization under the action of current pulses is first established .

当降低最终形变温度至铁素体区时，能够引入大量的晶体缺陷和形变储能，提高第二相的形核率，促进微合金元素的沉淀析出。

When the final deformation is in the ferrite region , a large number of crystal defects and deformation energy will be introduced . Then , the nucleation rate of the second phase will be improved , promoting the precipitation of micro-allying elements .

结果表明，随着脉冲频率的升高，浓差极化减小，晶核的形核率高，增长速率慢，复合镀层的组织得到细化，形成结晶细致、颗粒分散均匀的纳米复合镀层。

The results showed that texture of the composite coatings could be more refined and particles distributed more uniformly in the coatings as pulse frequency increased . Because nucleation rate of crystal nucleus increased and propagation rate of crystal nucleus was slow as pulse frequency raised and concentration polarization reduced .

同时也可以通过改变这些参数来增加反应的驱动力，增大非均匀形核的成核率。

And the driving force of chemical reaction and the heterogeneous nucleation rate can also be increased by adjusting these parameters .