等轴

Under the high frequency vibrating action, the crystal grain formed on the surface of the crystal nucleus eradiation equipment would be broken and peeled off, thereby ejected to zinc molten pool continuously and served as crystal nucleus source of equiaxed grain during solidification.

结果表明，当一种带有冷却结构且进行高频振动的晶核发射器插入锌液内时，锌液在晶核发射器表面迅速形核且长大，在高频振动作用下表面形成的晶粒将被折断剥离，从而连续不断地弹射到锌液中，成为凝固过程中形成大量等轴晶的晶核来源；采用带有水冷和气冷结构的晶核发射器对锌液进行振动激发形核处理后，锌凝固组织中的等轴晶率可分别提高到65%和80%。

One undercooling criterion of equi-nucleation is derived from analysis of Gaussian distribution model of heterogeneous nucleation.

通过对高斯异质形核公式的研究，给出了等轴晶开始形核的过冷度判据，更为准确的描述柱状晶向等轴晶的转变过程。

The main morphology of Fe3Si exhibited regular polygon equiaxial crystal and irregular equiaxial crystal.

Fe3Si相的形态主要呈现为规则的多边形等轴晶和不规则的等轴晶。

Moreover, the hot compressive deformation behavior of the RS/PM AZ91 magnesium alloy and AZ91 alloy matrix composite were also investigated, the conclusions are drawn as follows:1. The processing parameters of the atomization-twin rolls quenching technology were optimized as follows: the diameter of the nozzle 1mm, the wheel velocity 25m/s, the pressure of atomization gas 0.3MPa and Ar gas for melt injection 0.1MPa. The RS AZ91 alloy flakes exhibited fine and uniform microstructures. When the flakes were extruded at 673K, extruded velocity of 0.1mm/min and extrusion ratio of 25:1,the magnesium alloy rods with clean surface, uniform dimension and excellent mechanical properties were obtained.2. The RS AZ91 magnesium alloy powders prepared by atomization-twin rolls quenched technology exhibited fine equiaxed grains with the grain size of 1-3μm, the phase constituent included supersaturate solid solution phaseα-Mg and miner fineβ-Mg_(17)Al_(12) phase. The as-extruded materials also exhibited equiaxed grains with the size of 5-7μm and a large number of fineβ-Al_(12)Mg_(17) and fewer AlMg_2Zn phases were detected in the alloy.

本文还研究了快速凝固/粉末冶金AZ91镁合金热压缩变形流变应力行为，快速凝固/粉末冶金法原位生成Mg_2Si增强AZ91镁基复合材料，经过系统的研究，获得如下结论：1、雾化-双辊急冷法在下列工艺参数组合下：双辊线速度25m/s；喷嘴直径1mm；熔体压射压力0.1MPa；雾化气体压力0.3MPa。，可获得宏观尺寸细小、微观组织均匀细小、综合性能优良的的快速凝固AZ91镁合金细碎箔带，快速凝固箔带在挤压温度为673K、挤压速度为0.1mm/min，挤压比为25：1时，可获得的外表光洁、尺寸均匀、组织性能优异的镁合金棒材。2、雾化-双辊急冷法制备的AZ91镁合金粉末态为细小等轴晶组织，晶粒尺寸1-3μm，组织为α-Mg过饱和固溶体和微量的细小β-Mg_(17)Al_(12)相组成；粉末挤压棒材为等轴晶组织，晶粒尺寸5-7μm，组织中含有大量细小的β-Al_(12)Mg_(17)以及AlMg_2Zn析出相，室温力学性能，抗拉强度383MPa，屈服强度275MPa，断后伸长率7.5%。

The results show that the effect of addition or no-addition of degasser on grain refinement of Al-5.0%Si alloy ingot is...

结果表明，除气剂的添加与否对Al-5%Si合金铸锭组织的细化没有影响，铸锭由粗大的柱状晶组织构成；采用合适的超声波处理时间，Al-5%Si合金铸锭的等轴晶获得率大幅度提高，可使整个铸锭组织变为细化的等轴晶组织；超声波振动时间过长将导致铸锭内气孔的增加；根据克劳修斯-克拉柏龙方程，某一强度的超声波引起的压力冲击波作用，导致液相转变为固相，引起了超声波的细晶作用。

The integrated mathematic model of solidification is then established, which includes heat transfer, solute transfer, liquid flow and the movement of equiaxial crystals in solidification process.

本文通过两相流理论建立了等轴晶在对流金属液中移动的非稳态数学模型，推导了求解等轴晶在非稳态、非均匀液相流场中非稳态移动的数值表达式，并进一步推导了描述等轴晶在凝固过程中迁移、堆积规律的局部堆积方程式。

The microstructure of supercooling solidification is made up by four characteristic regions, from the sample bottom to top are: fine equiaxial dendrites, transition from fine equiaxial dendrites to columnar dendrites, columnar dendrites and coarse equiaxial dendrites.

5深过冷定向凝固的微观组织由四个特征区域组成，从试样底部到顶部依次为：细等轴晶区，细等轴晶→柱状枝晶的过渡区，柱状枝晶区和粗等轴晶区。

The influences of Ce on the microstructure and mechanics performances of Ti-Fe-Mo-Mn-Nb-Zr alloys were studied and presented in this paper. The microstructure of no-Ce Ti-Fe-Mo-Mn-Nb-Zr alloy was thick, long and dendritic,and the microstructure of alloy was fined by Ce. With the increase in Ce wt%, the microstructure became equiaxial gradually.

研究了稀土 Ce对 Ti- Fe- Mo- Mn- Nb- Zr合金组织与力学性能影响，结果表明：不含 Ce的为粗大的长枝晶组织，加入 Ce后组织有所细化，并随 Ce量增加而逐渐等轴化，直至形成等轴晶；硬度方面随 Ce的加入有所降低；在 Ce含量较少时随 Ce的增加压缩强度也增加，但当 Ce含量增大一定量时，Ce增加降低了压缩强度。

Solute diffusion controlled solidification model was employed to simulate the columnar to equiaxial transition of TiAl alloy casting. The simulation results show that solute shock wave occurs when the diffusion fields of columnar and equiaxial dendrites meet.

利用溶质扩散控制模型对TiAl合金柱状晶/等轴晶转变过程进行了数值模拟，结果表明，等轴晶在柱状晶前沿形核及生长过程中，当两个扩散场相遇时，观察到成分冲击波，它可能是导致柱状晶停止生长的一个主要原因。

Dense alloy coating without pore and inclusion is obtained which metallurgically bonded with steel but existing a few cracks. The results show that the cladding alloy coating is mainly composed of single-phase Fe3Al, and the microstructure is coarse equiaxed grain-groups that consist of large amount of fined slug like Fe3Al grains, between which some adjacent grains have the similar orientation.

试验获得了致密、无肉眼可见气孔、夹杂的合金层，合金层与基体间完全冶金结合，但存在裂纹现象；熔覆合金层主要由单相Fe3Al构成，覆层组织为粗大等轴状晶团，等轴状晶团由大量极细小的条状Fe3Al晶粒构成，一些相邻的条状晶粒之间具有基本一致的晶体学取向。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。