排序方式: 共有102条查询结果,搜索用时 31 毫秒
1.
研究了充有不同温度退火Fe基纳米晶粉芯LC回路的磁致频移特性(MFS),发现充有不同温度退火Fe基纳米晶粉芯LC回路的磁致频移不同,充有经600℃退火Fe基纳米晶粉芯LC回路的磁致频移最灵敏。 相似文献
2.
The laser cladding of Fe-based alloys on a medium carbon steel substrate was performed using a CO2 laser and Ar shielding gas that was blown into a molten pool. The microstructure and cracking susceptibility of the laser-clad layers were studied in terms of carbon additions. Results show that the small change of the carbon content in the alloy powders can obviously change the microstructure and properties of the layers. When the carbon content is in the range of 0.3–0.4 wt.%, the decrease of the carbon content in alloy powders will increase the hardness and toughness of the layers simultaneously under the same process parameters. As a result, crack-free coatings with high hardness can be obtained. As the carbon content increases from 0.2 wt.% to 0.4 wt.%, the segregation ratio of chromium increases, while the segregation ratios of nickel, manganese, and silicon first decrease and then increase. At the same time, a new designing principle concerning the composition and microstructure has been put forward, and the principal mechanisms of strengthening and toughening of the layers are fine-grain strengthening and low carbon martensitic phase transformation strengthening. 相似文献
3.
Role of compositional changes on thermal,magnetic,and mechanical properties of Fe-P-C-based amorphous alloys 下载免费PDF全文
Indah Raya Supat Chupradit Mustafa M Kadhim Mustafa Z Mahmoud Abduladheem Turki Jalil Aravindhan Surendar Sukaina Tuama Ghafel Yasser Fakri Mustafa Alexander N Bochvar 《中国物理 B》2022,31(1):16401-016401
This work aimed to tune the comprehensive properties of Fe-P-C-based amorphous system through investigating the role of microalloying process on the crystallization behavior,glass forming ability(GFA),soft magnetic features,and mechanical properties.Considering minor addition of elements into the system,it was found that the simultaneous microalloying of Ni and Co leads to the highest GFA,which was due to the optimization of compositional heterogeneity and creation of near-eutectic composition.Moreover,the FeCoNiCuPC amorphous alloy exhibited the best anelastic/viscoplastic behavior under the nanoindentation test,which was owing to the intensified structural fluctuations in the system.However,the improved plasticity by the extra Cu addition comes at the expense of magnetic properties,so that the saturation magnetization of this alloying system is significantly decreased compared to the FeCoPC amorphous alloy with the highest soft magnetic properties.In total,the results indicated that a combination of added elemental constitutes,i.e.,Fe69Co5Ni5Cu1P13C7 composition,provides an optimized state for the comprehensive properties in the alloying system. 相似文献
4.
中国需要自主发展煤炭间接液化工业化技术,以缓解油品供应的紧张局面,保障经济的可持续发展.近年来中国成功地进行了煤炭间接液化示范厂的运行,掌握了成熟可靠的费托合成催化剂技术和大型合成反应器技术,正在设计和建设百万吨级合成油商业厂.本文简要介绍了国内外煤炭间接液化技术发展状态,评述了我国煤炭间接液化技术在费托合成反应机理、催化剂研制、反应动力学、反应器设计、系统工艺集成、油品加工等方面从基础到工程技术的研究进展,分析了我国建设百万吨级煤炭间接液化商业厂需要解决的关键基础和工程技术问题,并对我国未来煤制油产业化发展的前景以及所面临的挑战与对策进行了展望. 相似文献
5.
Fe-based compounds with good environmental friendliness and high reversible capacity have attracted considerable attention as anode for lithium-ion batteries.But,similar to other transition metal oxides(TMOs),it is also affected by large volume changes and inferior kinetics during redox reactions,resulting in the destruction of the crystal structure and poor electrochemical performance.Here,Fe_3O_4/C nanospheres anchored on the two-dimensional graphene oxide as precursors are phosphated and sintered to build the multiphasic nanocomposite.XRD results confirmed the multiphasic nanocomposite composed of Fe_2O_3,Fe_3O_4 and Fe_3PO_7,which will facilitate the Li~+ diffusion.And the carbonaceous matrix will buffer the volume changes and enhance electron conduction.Consequently,the multiphasic Febased anode delivers a large specific capacity of 1086 mAh/g with a high initial Coulombic efficiency of 87% at 0.1 C.It also has excellent cycling stability and rate property,maintaining a capacity retention of~87% after 300 cycles and a high reversible capacity of 632 mAh/g at 10 C.The proposed multiphasic structure offers a new insight into improving the electrochemical properties of TMO-based anodes for advanced alkali-ion batteries. 相似文献
6.
Renato S. Gonnelli Mauro Tortello Dario Daghero Giovanni Alberto Ummarino Valeri A. Stepanov Jun S. Kim 《Central European Journal of Physics》2009,7(2):251-256
Point-contact Andreev-reflection (PCAR) experiments were performed in the Fe-1111 layered superconductor LaFeAsO0.9F0.1 with resistive T
c
on
∼ 27 K. The observation of two pairs of peaks in the low-temperature Andreev-reflection spectra clearly indicates the presence
of two order parameters. The behavior of the two gaps as a function of temperature, obtained by fitting the conductance curves
by means of the generalized two-band Blonder-Tinkham-Klapwijk model, shows some anomalies. A theoretical analysis performed
within the two-band Eliashberg theory with a generic electron-boson coupling can reproduce the low-temperature value of the
two gaps but generally fails in giving a satisfactory fit of their overall temperature dependence, indicating the rich and
complex physics of these newly discovered superconductors.
相似文献
7.
The thermodynamics structural relaxation of Fe73Cu1.5Nd3Si13.5B9 amorphous alloy from room temperature to 400°C has been investigated by measuring the structure factor with in situ X-ray diffraction. The structural information of the atomic configuration such as radial distribution function (RDF) and
neighbor atomic distance was gained by Fourier transformation. The research result shows that the amorphous structure remains
stable in the temperature range of 30 to 400°C but exhibits distinct changes in local atomic configuration with the increase
of temperature. The quantitative determination of the neighbor atomic distance suggests that the degree of short-range order
changes by the temperature altering the second nearest neighbor local atomic configuration of the amorphous when structural
relaxation occurs.
Supported by the Natural Science Foundation of Hebei Province of China (Grant No. A2007000296), the National Natural Science
Foundation of China (Grant No. 50731005), SKPBRC (Grant Nos. 2007CB616915 and 2006CB605201), and PCSIRT (Grant No. IRT0650) 相似文献
8.
9.
稀土对Fe基合金激光熔覆层抗磨性能的影响 总被引:17,自引:5,他引:17
在Fe基合金粉末中引入La2O3,通过激光熔覆得到了同基材结合良好的熔覆层,用扫描电子显微镜观察了稀土含量对熔覆层组织形貌的影响,用显微硬度计测量了熔覆层的硬度分布,并采用MM-200型摩擦磨损试验机考察了不同熔覆层在干摩擦条件下的摩擦磨损性能.结果表明,引入稀土有利于促进晶粒细化,提高熔覆层的组织均匀性及表面硬度,从而改善熔覆层的摩擦磨损性能. 相似文献
10.
The circular permeability μ′=μ′−jμ″ of two Fe-based soft magnetic wires with axial and transverse domains, has been determined from the measurements of impedance Z=R+jX as functions of frequency (f=10-105 Hz) and AC current amplitude (I=0.1-100 mA). From the magnetic spectra of μ′−f and μ″−f for a few circular fields (Hφ=0.4, 1.2, 4, 12, 40 A/m), we found that the sample with axial domain structure exhibits a relaxational feature, while for the one with transverse domain resonance-like spectra were observed when the circular field Hφ≥4 A/m. These results have been discussed in terms of domain structure and circular magnetization processes. 相似文献