过熔

With rising of Si concentration in the alloy melt, small Si-Si peaks were found in Gaussian separation of RDF of the melts, implying Si-Si clusters with covalence bond in the melt, whose area firstly reduce in low temperature range (below 875℃) and secondly increase in high temperature (over 875℃).

分解结果表明，在共晶与过共晶熔体结构中，存在着Si-Si共价键的小峰，该峰对应着熔体的Si原子集团，其数量随着温度的升高，在测量温度范围内先降低后升高。

The relationships of cleanness , undercooling and grain size of low carbon steel have been investigated by using of vacuum glass encasement levitation melting.

利用玻璃包熔真空悬浮熔炼等手段研究低碳钢的纯净度、过冷度与晶粒度之间的关系研究表明：随着包熔次数增加，钢中夹杂物含量减少，纯净度提高。

The sloping plate can provide sufficiently the under-cooling for nucleation and lay a foundation for heterogeneous nucleation to form lots of nuclei of crystal internally and on the sloping plate surface, thus causing the melt to nucleates eruptively. Under the action of both metal flow and vibration, the nuclei formed on the sloping plate surface can move freely and disperse into the melt, and they are able to maintain the direct growth in spherical shape in the homogeneous composition and temperature fields.

倾斜板为形核提供足够大的过冷度和异质形核基础，大量晶核在斜板表面和内部形成，使熔体爆发形核，在流动和振动作用下斜板表面形成的晶核游离，弥散到熔体内部，晶核在均匀的成分场与温度场条件下，可以保持直接球状生长。

Both the experimental results and theoretical analyses indicate that the remelting and breakup of the primary dendrites are induced by the chemical superheating of solid during recalescence rather than by the solid-liquid interface tension.

4实验结果和理论分析说明，初始枝晶组织的重熔瓦解是体系再辉过程中固相的化学过热引起的，固液界面张力作用下的重熔对组织形态的影响相对较小。

Micstructure and properties were investigated and dertermined. The results show that carbide structural inheritance of high chromium cast iron is obvious after remelt; carbide struc- tural inheritance was reduced with remelt times increasing; insulation can improve the carbide structural inheritance, but the longer insulation time was, the thicker ...

结果表明：高铬白口铸铁中的碳化物经过重熔仍存在明显的遗传现象；随着重熔次数的增加，碳化物组织遗传效应减弱，力学性能下降；保温处理可以改善碳化物的组织遗传性；过长的保温时间导致碳化物变得粗大，高铬白口铸铁的力学性能下降。

The results showed that the enhanced stirring action of the liquid metals in weld pool due to peak-current fluctuating periodically under single-wire synergic pulsed MIG welding decreased temperature gradients and increased heterogeneous nuclei within the region of constitutional supercool...

试验结果表明，单丝复合脉冲焊接时，峰值电流周期性变化引起的熔池液体强烈的搅拌作用，使熔池的温度梯度降低，固液界面前沿成分过冷区中的形核核心增加，促进了焊缝组织的细化，提高了焊缝的强度和塑性。

For supercooling directional solidification, ideal directional microstructure can be obtained only within the supercooling range 63～83K and 127～170K. These two supercooling ranges just corresponds to the supercooling for developed equiaxial dendrites in ordinary supercooling solidification.

6对于深过冷定向凝固来说，只有在63～83K的低过冷度范围和127～170K的中过冷度范围才能获得理想的定向生长组织，而这两个过冷度范围正好对应于深过冷熔体凝固组织为发达的等轴枝晶的过冷度范围，这种组织的相似性似乎与过冷度一样具有遗传性。

Evolution pattern of solidification microstructure in the monophase Cu Ni alloy in the range of thermo dynamically supercooling of 63～292 K is investigated, and both the condition of supercooling degree and orientation mechanism and control method of directional crystalline growth in the melt under negative temperature gradient are analyzed.

研究了 6 3～ 2 92K热力学过冷度范围内，Cu Ni单相合金的凝固组织演化规律，分析了负温度梯度熔体中晶体定向生长的过冷度条件以及晶体生长取向机制与控制方法。结果表明：(1)在临界过冷度ΔT (≈ 10 6K)附近，晶粒细化过程受溶质扩散控制，在临界过冷度ΔT (≈ 2 0 0K)附近，晶粒细化过程受热扩散控制；(2 )在 6 3～ΔT K范围内，晶体的生长方向是 [10 0 ]，在 12 7～ΔT K范围内，晶体的生长方向可以是 [10 0 ]，也可以是

Viscosities of the alloy in cooling are greater than those in heating.Viscosities in cooling with 100℃ superheating are lower than those in cooling without superheating.

熔体在降温过程中的粘度高于升温过程中，在过热100℃后的降温过程中熔体的粘度较之无过热的降温过程中要低。

During the course of experimentation the order of charging、the superheating temperature of aluminum melt、the temperature of holding、stirring and etc will be researched, who will affect the absorptivity of the elements in the master alloy Al-Ti-B-Re, and who will affect the shape、size and the distribution of the second phase; It will also be researched that the effect of the rear-earth to the declining of refiner、to the remelting property and to the refining property.

在实验中主要探讨了加料次序、熔体过热温度、静置温度、搅拌等工艺参数对Al-Ti-B-Re中间合金中各种元素吸收率的影响，对Al-Ti-B-Re中间合金组织中第二相形态、尺寸、分布及细化效果的影响；稀土元素对细化剂抗衰减性的影响，对细化剂重熔性能和重熔后细化性能的影响。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。