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非晶态合金焊接的研究进展 总被引:1,自引:0,他引:1
综述了近几年国内外非晶态合金在焊接方面的研究进展,简要分析了将大块非晶合金焊接成功的原因.目前可以成功焊接大块非晶合金的方法有:高压压实法、摩擦焊、闪光电阻焊、电子束焊、爆炸焊、激光焊.其中前两种焊接属于固相焊接,成功的原因主要是:块体非晶合金过冷液相区的热稳定性和超塑性.而其他几种属于液相焊接,成功的原因主要是:(1)非晶合金具有大的非晶形成能力;(2)焊接的能量高且集中,因而加热和冷却速度快于这些合金的临界冷却速度.大块非晶合金的焊接成功地推动了大块非晶合金在工程材料方面的应用. 相似文献
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非晶合金(又称金属玻璃)是一类新型的多组元合金材料,具有独特的无序原子结构。与原子处于平衡位置的晶体材料不同,亚稳态的非晶合金表现出许多优异的力学和物理化学特性,吸引了材料科学和凝聚态物理等多个领域的广泛关注。中国科学院物理研究所/北京凝聚态物理国家研究中心柳延辉、汪卫华团队近期在非晶合金领域引入材料基因工程理念,发展了独特的高通量实验方法,实现了非晶合金新材料的高效探索,成功研制出Ir-Ni-Ta高温非晶合金新材料体系。 相似文献
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近十年来块体非晶合金材料的研究现状及发展趋势 总被引:2,自引:0,他引:2
综述了现有的各种块体非晶合金(BMGs)体系及其主要性能特点、应用情况,分析了近十年来该领域的研究现状,认为当前的有关基础研究工作主要集中在新非晶合金体系的开发、不同变形方式下的变形行为及断裂机理、焊/连接工艺、复合强韧化、塑性成形及断裂过程的仿真模拟、微成形性能等几个方面;相关的应用研究,一是通过超塑性成型及各种连接技术实现常规尺寸非晶合金制件的加工;二是通过微塑性成型技术实现对微型器件的制造。最后,指出了实现非晶合金微型制件工业化、批量化生产所必须解决的几个关键问题。 相似文献
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块体非晶合金因其独特的原子结构而具有许多优异的力学性能,成为近年来材料领域的研究热点之一,但是由于其在变形过程中的室温脆性和应变软化等关键问题,一直制约其大规模工程应用。为解决此问题,块体非晶合金领域的研究者们提出了多种方案,其中利用"相变诱导塑性"概念制备块体非晶合金复合材料来韧塑化非晶合金成为卓有成效的方案之一,通过此方法成功地制备出同时具有拉伸塑性和加工硬化能力的非晶合金复合材料。然而,该类块体非晶合金复合材料要求的形成条件更严格,同时具有更复杂的多相协调变形过程和更独特的性能优化方案。从该类块体非晶合金复合材料的形成、性能特点、韧塑化机理及性能优化等方面进行综述,并对其未来发展进行了简要展望。 相似文献
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通过在Fe-Si-B-P合金体系中微合金化添加Mo元素,并提高铁含量,成功制备了具有较强非晶形成能力和优异软磁性能的非晶软磁合金。研究发现,Mo元素微合金化能有效提高合金的非晶形成能力,1%的Mo可以将该非晶合金体系的Fe含量极限提高到84%以上,从而得到了饱和磁感应强度(Bs)高达1.63 T的非晶合金。其中Fe80Si4.75B9.5P4.75Mo1非晶合金可以铸造形成非晶块体样品,临界直径达到1mm,饱和磁感应强度达到1.54 T,矫顽力为1.9 A/m。在整个成分范围内,该合金体系都具有1.9~5.1 A/m的低矫顽力和高于传统Fe-Si-B合金的饱和磁感应强度(Bs),具有较好的应用前景。 相似文献
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高熵非晶合金是一种新兴的合金材料,兼具高熵合金成分特征与非晶合金结构特征,因具有优异的机械物理性能与巨大的应用潜力而受到了广泛的关注.目前高熵非晶合金的研究处于起步阶段,本文介绍了高熵非晶合金成分设计的基本依据,着重分析了高熵非晶合金的关键物理参量(混合熵△Smix、混合焓△Hmix、原子错配度δ)等对高熵非晶材料组织结构的影响.当前已开发的高熵非晶合金材料体系有限,制备方法继承了非晶合金与高熵合金的制备特征,其制备手段大致可以分为:液相法、气相法以及固相法.由于其优异的热力学性能,高熵非晶合金有望通过热喷涂手段突破尺寸限制,实现大规模应用.高熵非晶合金性能的研究主要集中在力学性能、耐腐蚀性能、磁性能、非晶形成能力与热稳定性等方面.其中高熵效应对非晶形成能力的影响、高熵非晶合金的结构与热力学特性及高熵非晶合金的异常热稳定性等科学问题亟待解决.本文还展望了基于材料基因工程理念的高熵非晶合金材料体系研究及该类材料的应用前景. 相似文献
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铝基非晶合金因其独特的物理和化学性能在诸多领域具有广泛的应用前景,综述了铝基非晶合金的成分体系、制备方法、性能特点及应用研究进展。首先,介绍了铝基非晶合金的发展历史和成分体系,目前铝基非晶主要分为3大体系:二元、三元和多元体系,以及综合性能和形成能力2大方面,多元体系表现更佳,并逐渐向更多元化发展;其次,系统介绍了铝基非晶合金的制备方法,包括粉末状、薄带状、块体样品的制备,相较于非晶薄带的制备,块体和粉状的制备方法较为丰富,而粉状非晶通常作为铝基非晶涂层的预制材料;随后,详细介绍了铝基非晶合金的性能特点、应用现状及发展趋势,从性能上来看,铝基非晶在强度和硬度以及耐腐蚀性能上表现良好,目前主要以涂层的形式参与应用,除此之外,研究者们也开始对磁性和热塑性展开研究,由于玻璃形成能力的限制,作为结构材料的应用较少;最后,对其未来应用前景进行了展望,认为涂层是目前铝基非晶合金最具应用前景的工程化方式。 相似文献
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Nanoindentation studies on rapidly solidified Zr80Pt20 and Zr75Pd25 binary alloys with nanocrystalline, nanoquasicrystalline, and amorphous microstructures are reported. The results indicate that the hardness and elastic modulus are the highest for a mixture of amorphous and nanoquasicrystalline state among the various microstructures studied. Nanoquasicrystalline phase has high hardness and elastic modulus in comparison to amorphous and nanocrystalline phases. The hardness to modulus ratio is close to 0.1 in both the alloys, irrespective of the phase/phase mixture studied indicating that the bonding in these alloys is of covalent nature. In Zr80Pt20, all the phases/phase mixtures have higher hardness and modulus in comparison to similar microstructures in Zr75Pd25 due to higher bond energies caused by more negative heat of mixing in the former case. 相似文献
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Cold spraying (CS), a solid-state spraying technology, is expected to become an appropriate supplementary for traditional spraying methods owing to its plenty of merits such as high deposition efficiency, low temperature and little influence on the particles/substrate. The most reported researches are bulk alloys fabricated by CS. However, the systematic introduction and cold-sprayed metallic glass coatings have not been summarised. Therefore, in this paper, the international research status of CS including equipment structure, spraying process and parameters, advantages and disadvantages, deposit features and bonding mechanism were introduced. By using this technology, the successful researches about Fe-, Al-, Ni-, Cu- and Zr- based amorphous alloy coatings are reported. To overcome the limitations, further development and solutions were proposed. 相似文献
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LASER AND ELECTRON BEAM PROCESSING OF AMORPHOUS SURFACE ALLOYS ON CONVENTIONAL CRYSTALLINE METALS 总被引:2,自引:0,他引:2
K. Hashimoto N. Kumagai H. Yoshioka K. Asami 《Materials and Manufacturing Processes》1990,5(4):567-590
During last fifteen years various superior surface characteristics including extremely high corrosion resistance and unique electrocatalytic activity have been found for novel melt-spun ribbon-shaped amorphous alloys. Preparation of those amorphous alloys as surface alloys covering bulk conventional crystalline metals has been eagerly awaited for the purpose of utilizing their superior surface characteristics. This is a review of efforts devoted to developing methods for processing amorphous surface alloys by instantaneous melting of a very restricted volume of the surface by irradiation with a CO2 laser or electron beam and subsequent self quenching by the cold bulk substrates. Processing of a wide area by these high energy density beams requires heating the previously amorphized phase, which is easily crystallized by heating. Consequently, high energy density beam processing is most difficult among various methods for preparation of thermodynamically metastable amorphous alloys. Nevertheless, various amorphous surface alloys have been successfully prepared. The materials consisting of the amorphous surface alloys and bulk crystalline metals are quite suitable for corrosion resistant materials and electrodes for electrolysis of aqueous solutions. A comparison of CO2 laser and electron beam processing showed the superiority of the latter to the former because of a significantly shorter processing time. 相似文献
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Owing to their unique short- or medium-range ordered microstructures and excellent mechanical, physical, and chemical properties, amorphous alloys have attracted significant interest in recent years. For the application of amorphous alloys, clarifying their oxidation processes and mechanisms is necessary since many of the surface-related properties of amorphous alloys largely depend on the surface oxide layer. The aim of this paper is to review the recent research on the thermal oxidation behaviors of amorphous alloys under pure oxygen or air condition. The contents are divided into three categories according to the number of components the research considers, i.e., the oxidation of binary, ternary, and multi-component (>3) amorphous alloys. Each section discusses the thermal stability of the amorphous matrix, oxidation kinetics, and the oxide layer and amorphous substrate, which are strongly affected by internal factors (i.e., alloy elements and microstructure) and external factors (i.e., oxidation temperature, duration, and oxygen partial pressure, etc.). The general features of the oxidation of amorphous alloys – from simple binary to complex multi-component amorphous alloys – will be summarized. This overview of the current scientific understanding on the fundamentals of these materials may provide guidelines for the development of strongly corrosion-resistant amorphous alloys. 相似文献
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