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51.
52.
将铁水用75FeSi孕育后液淬,终止其溶解过程,在溶解区中出现已经生长石墨相的非金属夹杂物,它们随后又溶回铁水中去.但已经复盖有石墨相的晶核能存在较长的时间孕育剂的作用是提供一个碳的过冷溶液,使位于其中的非金属夹杂物活化成为晶核 相似文献
53.
The pressing bonding of steel plate to QTi3.5-3.5graphite slurry was studied. The bonding conditions were 620℃ for preheating temperature of steel plate, 530℃ for preheating temperature of dies, 50 MPa for pressure and 2 min for pressing time. The relationship between the solid fraction of QTi3.5-3.5graphite slurry and the interracial mechanical property of bonding plate was obtained. The results show that when the solid fraction of QTi3.5-3.5graphite slurry is smaller than 45.8%, the interracial shear strength of bonding plate increases with the increasing of solid fraction. When the solid fraction is larger than 45.8%, the interracial shear strength decreases with the increasing of solid fraction. When the solid fraction is 45.8%, the largest interracial shear strength of bonding plate 127 MPa can be got, and the interface is made up of Fe-Cu solid solution. 相似文献
54.
从国外引进的低液位组合结晶器,内置水套,石墨环镶嵌在结晶器四周内壁上,分上下两级水道。在铸造中,由于水质原因会造成喷水水眼堵塞,人为因素也会造成石墨环损坏,结晶器缺陷会造成铸造缺陷,严重时会生产不合格产品。从生产实践出发,对结晶器故障诊断、排除及日常维护技术进行了研究。 相似文献
55.
SiC陶瓷高温真空电阻炉的试验研究 总被引:1,自引:0,他引:1
SiC工程陶瓷是一种新型高性能材料。本文介绍了SiC陶瓷烧结用的高温真空电阻炉的结构及优化的电气控制系统,并进行了高温烧成试验。该炉采用高纯石墨发热体,运行中采用低真空和充入氩气保护(未达到高温前),以减少石墨发热体的蒸发。采用阶梯式升温。试验结果表明,该设备可稳定运行在2500℃,短时可达2800℃性能良好。发热体使用寿命长。 相似文献
56.
Different batches of natural graphite powders and electrographite powders were characterized by impurity, degree of graphitization, particle size distribution, specific surface area, and shape characteristics. The graphite balls consist of proper mix-ratio of natural graphite, electrographite and phenolic resin were manufactured and characterized by thermal conductivity, anisotropy of thermal expansion, crush strength, and drop strength. Results show that some types of graphite powders possess very high purity, degree of graphitization, and sound size distribution and apparent density, which can serve for matrix graphite of HTR-PM. The graphite balls manufactured with reasonable mix-ratio of graphite powders and process method show very good properties. It is indicated that the properties of graphite balls can meet the design criterion of HTR-PM. We can provide a powerful candidate material for the future manufacture of HTR-PM fuel elements. 相似文献
57.
Laser-assisted machining of compacted graphite iron 总被引:2,自引:0,他引:2
Compacted graphite iron (CGI) is a material currently under study for the new generation of engines, including blocks, cylinder liners, and cylinder heads. Its unique graphite structure yields desirable high strength, but makes it difficult to machine, thus resulting in a machining cost. Laser-assisted machining (LAM) is adopted to improve its machinability and hence machining economics. The machinability of CGI is studied by varying depth of cut, feed, and material removal temperature and then evaluating resultant cutting forces, specific cutting energy, surface roughness, and tool wear. At a material removal temperature of 400 °C and a feed of 0.150 mm/rev at a cutting speed of 1.7 m/s, it is shown that tool life is 60% greater than conventional conditions at a feed of 0.100 mm/rev. Surface roughness is improved 5% as compared to conventional machining at a feed of 0.150 mm/rev. CGI microstructure evaluated post machining by sectioning and polishing shows no change. An economic analysis shows that LAM can offer an approximately 20% cost savings for the machining of an engine cylinder liner. 相似文献
58.
郑思孝 《核技术(英文版)》1994,(2)
ACOMPLEX-TYPEFOCUSSEDMAGNETRONFORSPUTTERING¥ZhengSixiao(郑思孝)(InstituteofNuclearScienceandTechnology,SichuanUniversity,Chengdu... 相似文献
59.
Panpan Xu Darren H. S. Tan Binglei Jiao Hongpeng Gao Xiaolu Yu Zheng Chen 《Advanced functional materials》2023,33(14):2213168
As the dominant means of energy storage technology today, the widespread deployment of lithium-ion batteries (LIBs) would inevitably generate countless spent batteries at their end of life. From the perspectives of environmental protection and resource sustainability, recycling is a necessary strategy to manage end-of-life LIBs. Compared with traditional hydrometallurgical and pyrometallurgical recycling methods, the emerging direct recycling technology, rejuvenating spent electrode materials via a non-destructive way, has attracted rising attention due to its energy efficient processes along with increased economic return and reduced CO2 footprint. This review investigates the state-of-the-art direct recycling technologies based on effective relithiation through solid-state, aqueous, eutectic solution and ionic liquid mediums and thoroughly discusses the underlying regeneration mechanism of each method regarding different battery chemistries. It is concluded that direct regeneration can be a more energy-efficient, cost-effective, and sustainable way to recycle spent LIBs compared with traditional approaches. Additionally, it is also identified that the direct recycling technology is still in its infancy with several fundamental and technological hurdles such as efficient separation, binder removal and electrolyte recovery. In addressing these remaining challenges, this review proposes an outlook on potential technical avenues to accelerate the development of direct recycling toward industrial applications. 相似文献
60.
Qin Guo Cui Luo Wei Xiong Tianzi Yang Shuiqing Quan 《Fullerenes, Nanotubes and Carbon Nanostructures》2017,25(2):79-85
A stable dispersion in mixed solvent of water and N,N-dimethyl formamide (DMF) of graphene was synthesized by one-step electrochemical approach. Here we demonstrate about electrochemical stripping graphite to prepare graphene influence by different electrolytes. The physical and chemical properties of the stripping product had been characterized by using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), UV-Vis spectrophotometer (UV-Vis), Scanning electron microscopy (SEM), Transmission Electron Microscope (TEM) . The characteristic results of XRD showed that it could improve the efficiency of graphite stripping when H2SO4 was used as electrolyte mother liquid and amount of HNO3 was doped in electrolyte; XPS and FTIR results indicate that the electrochemical stripping products preserve the intrinsic structure of graphene. The results of SEM and TEM shown that the surface morphology of the as-prepared graphene was folded lamellar structure and have good transparency;its thickness varies from 0.8 nm to a few nanometers. 相似文献