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本文主要介绍了Ni-Al/Al2O3、Ti-Al/Al2O3和Fe-Al/Al2O3三种复合材料的最新研究进展情况,对它们的最新研究动态进行了综述。着重介绍了Fe-Al/Al2O3的研究进展,并认为Fe-Al/Al2O3是一种应用前景非常广阔的新型材料,添加合金元素是进一步提高其性能的重要途径。 相似文献
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采用SHS/PHIP工艺制备了致密的TiC-Al2O3-Fe系金属陶瓷,研究了延迟时间,高压特续时间,压力及Fe含量对合成TiC-Al2O3-Fe金属陶瓷实度的影响,结果表明,采用SHS/PHIP技术制备了TiC-Al2O3-Fe系金属陶瓷时,合成产物中气体的排放,液相的存在及组成相之间的润湿性是制备密实材料的关键。 相似文献
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掺杂聚苯胺磁化率的研究 总被引:6,自引:0,他引:6
分别研究了浓H2SO4掺杂本征态聚苯胺(PAn)、HCl掺杂PAn以及FeCl3掺杂这两种聚安在地的磁化率。通过研究磁化率的变化曲线,我们得到了一些有意义的结果:浓H2SO4掺杂PAa和HCl掺杂PAn的磁化率变化规律不同;FeCl3掺杂浓H2SO4-PAn材料可以获得比FeCl3掺杂HCl-PAn材料更高的磁化率;FeCl3在掺杂HCl-PAn材料和浓H2SO4-PAn材料时,FeCl3在这两种 相似文献
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Fe3Al基合金作为一种金属间化合物新型结构材料越来越引起人们的重视,极有可能在许多场合得到应用。但是Fe3Al合金室温时的低塑性和低的断裂抗力以及高于600℃时强度的急剧下降妨碍了它的工程应用,本文主要综述近几年来Fe3Al金属间化合物机械性能方面的研究情况。 相似文献
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Fe3Al金属间化合物强韧化研究进展 总被引:7,自引:0,他引:7
Fe3Al基合金作为一种金属间化合物新型结构材料越来越引起人们的重视,极有可能在施工场合得到应用。但是Fe3Al合金室温时的低塑性和低的断裂抗力以及高于600℃时强度的急下降妨碍了它的工程应用,本文主要综述近几年来Fe3Al金属间化合物机械性能方面的研究情况。 相似文献
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Qiang Li Sichuang Xue Jian Wang Shuai Shao Anthony H. Kwong Adenike Giwa Zhe Fan Yue Liu Zhimin Qi Jie Ding Han Wang Julia R. Greer Haiyan Wang Xinghang Zhang 《Advanced materials (Deerfield Beach, Fla.)》2018,30(11)
Light‐weight aluminum (Al) alloys have widespread applications. However, most Al alloys have inherently low mechanical strength. Nanotwins can induce high strength and ductility in metallic materials. Yet, introducing high‐density growth twins into Al remains difficult due to its ultrahigh stacking‐fault energy. In this study, it is shown that incorporating merely several atomic percent of Fe solutes into Al enables the formation of nanotwinned (nt) columnar grains with high‐density 9R phase in Al(Fe) solid solutions. The nt Al–Fe alloy coatings reach a maximum hardness of ≈5.5 GPa, one of the strongest binary Al alloys ever created. In situ uniaxial compressions show that the nt Al–Fe alloys populated with 9R phase have flow stress exceeding 1.5 GPa, comparable to high‐strength steels. Molecular dynamics simulations reveal that high strength and hardening ability of Al–Fe alloys arise mainly from the high‐density 9R phase and nanoscale grain sizes. 相似文献
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Impurity effects on the nucleation and growth of primary Al3(Sc,Zr) phase have been investigated in high purity Al alloys and commercial purity Al alloys, respectively. In the case of high purity Al alloys, primary Al3(Sc,Zr) phases were found to be pushed to grain boundaries ahead of the solidification front. Such type of primary Al3(Sc,Zr) phase did not contribute to the heterogeneous nucleation, and thereby the grain refinement of Al alloys. In the case of commercial purity Al alloys, the presence of Fe, Si, Cu, Mg, Ti, and other impurities significantly enhanced the heterogeneous nucleation of primary Al3(Sc,Zr) phase. Most primary Al3(Sc,Zr) phases were found to be located within the α-Al matrix, and kept an identical orientation relationship with the α-Al matrix. Furthermore, the presence of the impurities also changed the growth mode on the primary Al3(Sc,Zr) phase. In the case of commercial purity Al alloys, a peritectic to eutectic reaction was induced due to the presence of the impurities. A layered growth was observed leading to a narrow particle size distribution. In contrast, in the case of high purity Al alloys, a featureless structure was observed. This investigation demonstrates that impurities and their concentrations are important factors affecting the nucleation and growth of primary Al3(Sc,Zr) phases, and thereby for the successful grain refinement in Al-based alloys. 相似文献
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Environmental Embrittlement in A_3B-type Intermetallic Alloys 总被引:1,自引:0,他引:1
Environmental embrittlement in A3B-type intermetallics based on Ni3Al and Fe3Al has been studied in this paper. For the Ni3Al doped with 120 wt ppm B and Ni,(Al,Cr.Zr) doped with 80 wt ppm B,their elongation and ultimate tensile strength decreased in the sequence:of vacuum > air >hydrogen. while for Ni,(Al,Mn) doped with 400 wt ppm B no envifonmental degradation was ob served, although a -Ni3(Al,Mn) alloy without B showed a decrease in ductility when tested in air in stead of oxygen. It is supposed that boron and hydrogen compete for the occupation of interstitial sites near grain boundaries. If boron content is sufficiently low, hydrogen embrittlement occurs ;however, if its content is sufficiently high. boron addition is capable of eliminating envjronmental ef fect in Ni3Al-based alloysi As to the micromechanism of hydrogen embrittlement in Ni3Al+B. S EM in situ observations showed that both grain boundary decohesion and a high stress concentration con tributed to hydrogen-assisted jntergranu lar cracking in this alloy. For the Fe3Al and Fe3 (Al.Cr) alloys.their mechanical properties depended strongly on grain size / grain shape and testing environment. A strain rate effect on ductiIity and fracture strength was also observed in the Fe3Al and Fe,(Al,Cr)+B aIloys. Preoxidation increased the ductility of the Fe,(Al,Cr)+B alloy. All these results can be rationalized from a hypothesis that surface reaction is the controlling process in embrittling Fe3Al-based alloys. 相似文献
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Fe3Si基合金的制备及应用研究进展 总被引:17,自引:2,他引:15
Fe3Si基合金具有优异的软磁性能,不仅有希望硅钢片(在高频信息领域),而且还广泛用作音几视频磁头材料和卡片阅读器用磁头材料。本文综述了Fe3Si基合金的制备工艺及应用,并结合我们的研究工作,分析了其研究现状,简要论述了其发展前景。 相似文献
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Bo Lin Haoyu Li Rui Xu Ya Shi Huaqiang Xiao Weiwen Zhang 《Materials Science & Technology》2013,29(17):2145-2152
Effects of added Al–5Ti–B master alloys on precipitation of iron-rich intermetallics and mechanical properties of A356 cast alloys with high Fe content (1.5?wt-%) were investigated using image analysis, scanning electron microscopy, and tensile testing. Results show that added Al–5Ti–B has apparent refinement on α (Al) grain size of A356 alloys that have high Fe content. 12?wt-% Al–5Ti–B is beneficial for improving mechanical properties of A356 cast alloys with high Fe content. Improved mechanical properties can be attributed to refined microstructure, the proper amounts of TiB2 and Ti(AlSi)3, and decreased porosity. An excessive amount of Al–5Ti–B deteriorates mechanical properties of alloys because it leads to the formation of large secondary intermetallics and increased porosity. 相似文献
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Pedro R. Goulart José E. Spinelli Noé Cheung Amauri Garcia 《Materials Chemistry and Physics》2010,119(1-2):272-278
The aim of the present investigation was to contribute to provide a basis for understanding how to control solidification parameters, microstructure and mechanical strength of Al–Fe alloys. Upward directional solidification experiments have been carried-out with commercially pure Al and Al–0.5 wt.% Fe, Al–1.0 wt.% Fe and Al–1.5 wt.% Fe alloys. The tensile tests results have been correlated to cell spacing (λ1), since cellular growth has prevailed along all obtained Al–Fe castings. The used casting assembly was designed in such way that the heat was extracted only through the water-cooled system at the bottom of the casting. In order to investigate the nature of Al–Fe intermetallic fibers, they were extracted from the aluminum-rich matrix by using a dissolution technique. These fibers were then investigated by SEM-EDAX microscopy. It was found that the ultimate tensile strength, yield tensile strength and elongation increase with decreasing cell spacing. The highest ultimate tensile strength was that obtained for the most refined microstructure, i.e. for the Al–1.5 wt.% Fe alloy sample, where a higher density of eutectic fibers was found distributed in a more homogeneous way along the casting section due to lower cell spacings. In contrast, the elongation was found to decrease with increasing solute content. 相似文献
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基于合金化的改性原理,以调整材料的长程有序度为改性思想,采用真空电弧熔炼/热压退火制备了四种Cr/Al复合合金化Fe3Si基有序合金。通过XRD,SEM,EPMA等对合金进行了表征,并采用长程有序参数定量表征了退火得到的有序相的有序程度。结果表明:四种不同成分的有序合金,具有不同的显微组织。随着Si含量降低合金有序度下降,且Cr/Al的复合效应对这一趋势起到了促进作用,使得具有相同Si含量的Fe65Si25Cr5Al5有序合金的有序度低于Fe3Si,分别为0.658和0.796。 相似文献