覆层

The cladding layers are composed by ternary boride based hard phase and binder phase of α-Fe.

四种硬质覆层材料的硬质覆层都是由硬质相三元硼化物和粘结相体心立方α铁组成。

Using Mo powder,Fe-B alloy powder,and Fe powder as raw materials,and adding Cr,Ni and C alloy and agent polyvinyl butyral,Mo_2FeB_2 hard alloy was clad on a Q235 steel substrate to form a new type of cladding material with excellent wear and cor- rosion resistance property by means of vacuum liquid phase sintering technique.

以Mo粉、Fe-B合金粉、Fe粉为基本原料，掺加适量合金元素Cr，Ni，C，以及有机粘结剂聚乙烯醇缩丁醛，采用真空液相烧结法在Q235钢基体表面制备Mo_2FeB_2硬质合金覆层，获得了力学性能良好且耐磨抗蚀的新型硬质合金覆层材料。

Results have theoretical significance to the design and optimization of cladding parts and to more applications of the cermet cladding material.

文中的研究结果对金属陶瓷硬质覆层零件的设计、优化以及金属陶瓷硬质覆层材料的进一步推广应用具有重要的理论指导意义。

The propagation of interface cracks, the chemical reaction and element diffusion at the interface zone has been studied.

研究了此种新型覆层材料硬质覆层和钢基体之间界面裂纹扩展的情况以及在界面区域的化学反应和元素的扩散。

There is bunchiness Eutectic under the cladding layer, there is lots of black block and columniation crystal structure, in the middle part of the cladding layer.

熔覆层底部近结合区呈束团状的共晶组织，熔覆层中部区域有大量的黑灰色的块状和柱状晶组织，整个熔覆区还存在着大量灰白色的条块状组织。

The theoretical results demonstrates that the mechanical transfer characteristics of double coating depend on the relative magnitude of elastic modulus between cladding and buffer under the small radius approximation compared with the model of single coating.

理论研究表明：在小半径近似条件下，双涂层光纤的力学传递特性决定于涂覆层和缓冲层的弹性模量的相对值；当缓冲层的弹性模量远大于涂覆层时，其作用可忽略。

The results prove that using the laser power P=1.7Kw, scanning velocity V=4mm/s, spot diameter D=3mm, cladding thickness T=0.6mm, 50%: 50% Ni60:Ni-Cr-Cr_3C_2 as laser cladding process can obtain the laser coating with lubricous tight surface, tiny dilution rate ,fining microstructure and higher micro hardness and fine metallurgical-bonding Interface.

试验结果最终证明，激光熔覆工艺参数对熔覆层的宏观形貌、微观组织及涂层性能有极大的影响，在激光熔覆工艺参数为功率P=7Kw，速度Vs=5mm/S光斑直径D=3mm，厚度T=0.6mm，50%；50%的Ni60；Ni-Cr-Cr_3C_2的条件下，所得到熔覆层表面光滑致密、组织细小均匀、稀释率小、硬度高且与基体实现了良好的冶金结合，证明这种方法是一种在提高热锻模寿命方面有前途的方法。

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。

Inorganic salts produced in combustion of pyrotechnically generating aerosol fire extinguishing agent are strongly hygroscopic and potentially corrosive to metal surfaces in humid circumstances.

针对固体微粒气溶胶灭火剂对金属材料表面产生腐蚀性的问题，在气溶胶发生装置的释放通路中，通过汽化的十八胺对气溶胶固体颗粒进行原位表面包覆，采用扫描电镜和光电子能谱表征了包覆效果，对包覆前后气溶胶粒子的吸湿性和腐蚀性进行测试，结果表明有机包覆层的存在有效抑制了气溶胶颗粒的吸湿，达到了降低灭火气溶胶对铜片腐蚀性的目的

One factor could be deposits of dust and black carbon upon the snow, which, up to an accumulation of 400 grams per square meter sharply raises the rate of melting. Between 400 and 600 grams, it has no further effect, but when it exceeds 600 grams, it acts as a shield against the sun, and slows down melting.

雪上尘埃和黑炭覆层可能是其中一个因素：当覆层的积累达到每平方米400克的时候，会急剧加快融化的速度；每平方米在400克至600克之间时，不再有进一步的影响；但是当每平方米超过600克时，覆层就起到遮挡阳光的作用，从而减缓融化的速度。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失