镁基非晶合金的研究进展

综述了大块镁基非品态合金的合金体系、介绍了镁基大块非晶态合金的生产和应用现状,领域有重大发展潜力。制备方法、各种独特性能及其最新研究进展。展望了镁基非晶态合金将在3C产品和生物医用     

非晶态合金的制备与研究进展

回顾了非晶态合金的发展历史,介绍了制备非晶态合金的方法,分析了非晶态合金形成过程的热力学与动力学机制,介绍了非晶态合金的性能及最新研究进展.最后对非晶态合金的研究前景进行了展望.     

块体非晶合金制备方法的研究进展

对大块非晶合金的制备方法进行了总结争归纳,阐述了不同制备方法的基本原理,并对各种制备方法的优缺点进行了讨论.最后根据对不同制备方法的分析及探讨,对大块非晶合金制备方法的研究方向进行了展望.     

Zr57Nb5Cu15.4Ni12.6Al10大块非晶合金的晶化动力学及显微硬度

采用铜模铸造法制备直径10 mm的圆柱状Zr57Nb5Cu15.4Ni12.6Al10大块非晶合金,并用X射线衍射(XRD)证明其为完全非晶态.应用示差扫描量热(DSC)分析方法测定该合金的玻璃转变的热学参量并分析其晶化过程.利用Kissinger法和Ozawa法计算了大块非晶合金表观晶化激活能.同时研究了退火温度对非晶合金显微硬度的影响.     

等离子弧喷涂法制备铁基非晶合金的研究

非晶态合金具有强度、韧性以及耐磨性能优于普通晶态金属材料,耐蚀性好,磁抗小等优点,倍受材料科学和工程技术人员的关注,但是非晶态材料只有在非平衡条件下才能形成,加工难度大,阻碍了非晶态材料的发展和应用.对此,采用等离子弧喷涂方法制备铁基非晶合金,制备了Fe79Si10B11非晶态合金.对制备的非晶合金进行了XRD和TEM分析,并研究了喷涂过程中粒子的飞行温度和速度,通过传热学方法计算了喷涂过程中的粉末冷却速度.结果表明,所制备的非晶合金组织均匀,喷涂过程冷却速度达4.16×107 K/s.     

Ti45Zr15Ni10Cu30大块非晶态合金的制备及热稳定性

直接用水冷快淬法成功制备直径２～５ｍｍ球状Ｔｉ４５Ｚｒ１５Ｎｉ１０Ｃｕ３０大块非晶态合金。Ｘ射线衍射（ＸＲＤ）实验检验证明样品完全为非晶态。Ｔｉ４５Ｚｒ１５Ｎｉ１０Ｃｕ３０非晶合金于不同温度进行１０ｍｉｎ等温热处理,采用Ｘ射线衍射分析了Ｔｉ４５Ｚｒ１５Ｎｉ１０Ｃｕ３０非晶合金的晶化过程。     

高压放电法制造非晶合金薄带高密度结合体

高压放电法制造非晶合金薄带高密度结合体非晶态合金具有优异的磁特性，耐蚀性和力学性能等特性，在利用其软磁特性的领域中已得到有效实用化，但是为了更广泛的工业应用，开发大块非晶态合金十分重要。在非晶态合金大块化方面，粉末的固化成形技术是有效的，但将非晶态合...     

Zr57Nb5Cul5．4Nil2．6Al10大块非晶合金的晶化动力学及显微硬度

采用铜模铸造法制备直径10mm的圆柱状Zr57Nb5Cu15.4Ni12.6Al10大块非晶合金，并用X射线衍射(XRD)证明其为完全非晶态。应用示差扫描量热(DSC)分析方法测定该合金的玻璃转变的热学参量并分析其晶化过程。利用Kissinger法和Ozawa法计算了大块非晶合金表观晶化激活能。同时研究了退火温度对非晶合金显微硬度的影响。     

大块非晶合金制备技术

结合作者近年来在喷射成型法和吸铸法制备大块非晶合金中的研究结果,概述了当今大块非晶合金制备领域的最新研究成果.采用图文并茂的形式,较为详细地介绍了目前国内外研究和应用较为集中的采用液态金属凝固法制备大块非晶合金的方法和原理,并简要分析和比较了常用的液态金属凝固法制备大块非晶合金工艺的优缺点和适用材料.为从事亚稳态金属研究提供了详实的参考.     

高耐蚀性大块非晶态Ni-(Co)-Nb-Ti-Zr合金

自从镧系金属基、镁基和锆基大块非晶态合金开发成功以来 ,近十年来又相继开发了一系列多元系大块非晶态合金 ,特别是锆基和钯 -铜基大块非晶合金已实际应用作为体育用品和电极材料。近来采用铜模铸造法成功地合成了Ｎｉ Ｎｂ Ｔｉ Ｚｒ基大块非晶合金 ,它不含类金属元素 ,具有高强度高韧性 ,而且耐蚀性好。日本东北大学的研究者新近系统地研究了Ｎｉ (Ｃｏ )Ｎｂ Ｔｉ Ｚｒ系合金的非晶形成能力以及大块非晶态合金的热稳定性和腐蚀行为。研究用的是具有Ｎｉ6 0 -ｘＣｏｘＮｂ2 0 Ｔｉ10 Ｚｒ10 (ｘ =0 ,5 ,10 ,15 ,2 0 ,30 ,4 0和 5 0 %原…     

块体非晶合金的应用与连接

综述了块体非晶合金在国内外的应用现状、前景,以及目前对块体非晶合金连接的研究现状.报导了采用液相焊接方法如爆炸焊、电子束焊、激光焊等和超冷液相焊接方法如摩擦焊成功实现同质、异质块体非晶合金以及块体非晶合金与晶态合金的连接.分析了实现液相焊接块体非晶合金的关键是采用高能量密度的焊接方法以及块体非晶合金具有强的玻璃形成能力;实现超冷液相焊接块体非晶合金的关键在于块体非晶合金处于过冷液态的热稳定性、超塑性和粘滞性.     

超高强钴基块体非晶合金的组成设计

块体非晶合金是一类具有高强度、高硬度和大弹性极限的无序金属材料,其优异的力学性能是目前先进金属材料领域研究热点之一,如何提高材料的强度是材料研究领域永恒的主题。系统地总结了已知具有超高强度的一类块体非晶合金材料——钴基块体非晶合金的成分、热学稳定性及力学性能;同时研究了不同非晶合金的断裂强度与其弹性常数、硬度和特征温度的关联。研究结果表明：在非晶合金体系中杨氏模量、维氏硬度、玻璃转变温度与断裂强度之间都存在较好的线性变化关系。基于以上结果,本课题组提出了超高强钴基块体非晶合金的组成设计方法,即选取具有强共价键特性的非金属元素和高模量、高熔点过渡金属元素与钴元素进行组合。     

An approach to modeling the S–N behavior of bulk-metallic glasses

Probability and statistics analyses are increasingly being used for reliability and durability assessments for life predictions of advanced material systems. Fatigue-life predictions have historically been based on crack-growth approaches, which are almost exclusively empirically based. Consequently, they often do not adequately reflect long-term operating conditions, which are well beyond laboratory test conditions. These models usually fail to identify the sources of the randomness and the extent of their contributions to the total variability. Using a simple crack-growth model, the variability inherent in the stress vs. fatigue-life (S–N) response for bulk-metallic glasses (BMGs) can be related to some of the key random variables that are readily identified in the models. The identification and quantification of these variables are paramount for predicting fatigue lives and reaching some understanding of the fundamental damage growth mechanisms in BMGs. The effectiveness of the modeling is shown through the analyses of a set of S–N data for BMGs where the variability associated with the material chemistry and structure and specimen preparation is considered.     

The fracture toughness of bulk metallic glasses

Stiffness, strength, and toughness are the three primary attributes of a material, in terms of its mechanical properties. Bulk metallic glasses (BMGs) are known to exhibit elastic moduli at a fraction lower than crystalline alloys and have extraordinary strength. However, the reported values of fracture toughness of BMGs are highly variable; some BMGs such as the Zr-based ones have toughness values that are comparable to some high strength steels and titanium alloys, whereas there are also BMGs that are almost as brittle as silicate glasses. Invariably, monolithic BMGs exhibit no or low crack growth resistance and tend to become brittle upon structural relaxation. Despite its critical importance for the use of BMGs as structural materials, the fracture toughness of BMGs is relatively poorly understood. In this paper, we review the available literature to summarize the current understanding of the mechanics and micromechanisms of BMG toughness and highlight the needs for future research in this important area.     

Fabrication of bulk metallic glasses at the region of multiple quasi-peritectic reactions

We report that Ca-Cu-Mg bulk metallic glasses (BMGs) can be fabricated at the region of multiple quasi-peritectic reactions by a conventional copper mold casting method, demonstrating that finding a deep eutectic composition is not the sole solution for the fabrication of BMGs. Unusual relationship between the glass transition temperature and the elastic constants of these BMGs were discussed in comparison with other BMGs. These results have implications for exploring new BMGs and understanding the glass formation mechanism.     

Heavy rare earth based bulk metallic glasses with high thermal stability

We report a family of ternary Gd–Al–Co alloys based on the heavy gadolinium rare earth element can be readily cast into fully glassy rod by a conventional casting method. It is found that the bulk metallic glasses (BMGs) have much high thermal stability (i.e. high glass transition temperature and crystallization temperature) and high moduli compared with those of other known rare-earth based BMGs. It is confirmed that, in addition to the strong chemical interaction among the components, the high bulk modulus of the base component in the BMGs is dominantly responsible for the high thermal stability. The thermal stability is correlated with the bulk modulus of the base element in the rare earth based BMGs.     

基于增材制造技术的非晶合金研究进展

近年来,为了满足具有大尺寸复杂结构的非晶合金构件的市场需求,具有高度柔性化成形、机加工量小和成形精度高等特点的增材制造技术被成功应用于制备块体非晶合金。本文基于国内外块体非晶合金增材制造成形领域的最新研究成果及作者们多年来在该领域的研究工作,系统介绍了现有非晶合金增材制造技术的研究现状,详细阐述了非晶合金在各类增材制造技术中的成形机理和性能方面的研究进展,深入探讨了现有非晶合金增材制造成形的技术难点,详细阐明了非晶合金增材制造成形工艺 - 组织结构 - 性能间内在联系,指出制备高质量高性能非晶构件将是块体非晶合金增材制造成形领域未来研究的重要方向。     

具有低脆性参数的Zr-Al-Ni-Cu玻璃形成合金

采用铜模铸造法制备出一系列Zr-Al-Ni-Cu块体非晶合金,其脆性参数值分别采用Arrhenius和Vogel-Fulcher-Tammann （VFT）方法进行计算。结果表明,这些非晶合金具有低的脆性参数值,其原因可能与网络状的微观结构有关。另外,Zr-Al-Ni-Cu合金的脆性参数值可以通过Zr含量进行调整,当Zr含量接近54%（摩尔分数）时,Zr-Al-Ni-Cu合金,即Zr 54 Al 13 Cu 18 Ni 15合金的脆性参数值最小,约为13。     

Effect of metalloid elements on magnetic properties of Fe-based bulk metallic glasses

In this work, we successfully prepare Fe₈₀(P, C, B)₂₀ bulk metallic glasses (BMGs) with the different content of P, C, B by combining fluxing treatment and J-quenching technique, and the effects of the metalloid elements (P, C, B) on the thermal stability and magnetic properties of the present Fe₈₀(P, C, B)₂₀ BMGs are investigated systematically. It is found that the replacements of P or B by C and P by B enhance the thermal stability of Fe₈₀(P, C, B)₂₀ BMGs. The substitutions of B for C or P and C for P result in the increase of both the saturation magnetization and the Curie temperature of Fe₈₀(P, C, B)₂₀ BMGs.     

Progress in studying the fatigue behavior of Zr-based bulk-metallic glasses and their composites

Zr-based amorphous alloys with a high glass-forming ability and thermal stability were discovered in 1990. In the following years, the alloy design increased the critical casting thickness to several centimeters, and a homogeneous dispersion of nanoscale particles was found to improve the ductility. Therefore, Zr-based bulk-metallic glasses (BMGs) are being studied widely because of their potential as structural materials. The fatigue behavior is an important characteristic of structural materials. The current review documents the fatigue studies of Zr-based BMGs and their composites. The fatigue characteristics of these alloys in different loading conditions and environments are summarized and compared in this paper. The factors affecting the fatigue behavior of the Zr-based BMGs and their composites are discussed. The mechanisms of fatigue-crack initiation and propagation in BMGs are addressed in this review. In order to broaden the scope of applications of BMGs, a fundamental understanding of the fatigue behavior is important for the design of new alloy systems and the development of the processing techniques.