Technology & Engineering
Bulk Metallic Glasses
Bulk Metallic Glasses (BMGs) are a type of amorphous metal that exhibit unique mechanical, physical, and chemical properties. They are formed by cooling molten metal at a rate that prevents the atoms from arranging themselves in a crystalline structure. BMGs have potential applications in various fields, including aerospace, biomedical, and consumer electronics.
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eBook - PDFBulk Metallic Glasses and Their Composites
Additive Manufacturing and Modeling and Simulation
- Muhammad Musaddique Ali Rafique(Author)
- 2021(Publication Date)
- De Gruyter(Publisher)
Section 2 Bulk Metallic Glasses (BMGs) and bulk metallic glass matrix composites (BMGMCs) 2.1 Metallic glasses (MG) and Bulk Metallic Glasses (BMGs)/monoliths Metallic glasses (MG) [5] may be defined as “ disordered atomic-scale structural ar-rangement of atoms formed as a result of rapid cooling of complex alloy systems directly from their melt state to below room temperature with a large undercooling and a suppressed kinetics in such a way that the supercooled state is retained/fro-zen ” [113 – 116]. This results in the formation of a “ glassy structure. ” The process is very much similar to inorganic/oxide glass formation in which large oxide mole-cules (silicates/borides/aluminates/sulfides and sulfates) form a regular network re-tained in its frozen/supercooled liquid state [117], the only difference being MG are comprised of metallic atoms rather than inorganic metallic compounds. Their atomic arrangement is governed by mismatch of atomic size and quantity (minimally three) [118] (described in the next section) and is based on short-range order (SRO) [119 – 121] to medium-range order (MRO) [122 – 124] or long-range disorder [4] (unlike metals – well-defined long-range order) and can be explained by other advanced theories/ mechanisms (frustration [125], order in disorder [123, 125, 126] and confusion [127]). Important features characterizing them are their amorphous microstructure and unique mechanical properties. Owing to absence of dislocations, no plasticity is exhibited by BMGs. This results in very high yield strength and elastic strain limits as there is no plane for material to flow (by conventional deformation mecha-nisms). From a fundamental definition point of view, MG are typically different from bulk metallic glass (BMG) in that the former has fully glassy (monolithic) structure for thicknesses less than 1 mm, while the later is glassy (monolithic) is greater than 1 mm [6, 7].
eBook - ePubBulk Metallic Glasses and Their Composites
Additive Manufacturing and Modeling and Simulation
- Muhammad Musaddique Ali Rafique(Author)
- 2021(Publication Date)
- De Gruyter(Publisher)
Section 2 Bulk Metallic Glasses (BMGs) and bulk metallic glass matrix composites (BMGMCs)2.1 Metallic glasses (MG) and Bulk Metallic Glasses (BMGs)/monoliths
Metallic glasses (MG) [5 ] may be defined as “disordered atomic-scale structural arrangement of atoms formed as a result of rapid cooling of complex alloy systems directly from their melt state to below room temperature with a large undercooling and a suppressed kinetics in such a way that the supercooled state is retained/frozen” [113 , 114 , 115 , 116 ]. This results in the formation of a “glassy structure.” The process is very much similar to inorganic/oxide glass formation in which large oxide molecules (silicates/borides/aluminates/sulfides and sulfates) form a regular network retained in its frozen/supercooled liquid state [117 ], the only difference being MG are comprised of metallic atoms rather than inorganic metallic compounds. Their atomic arrangement is governed by mismatch of atomic size and quantity (minimally three) [118 ] (described in the next section) and is based on short-range order (SRO) [119 , 120 , 121 ] to medium-range order (MRO) [122 , 123 , 124 ] or long-range disorder [4 ] (unlike metals – well-defined long-range order) and can be explained by other advanced theories/mechanisms (frustration [125 ], order in disorder [123 , 125 , 126 ] and confusion [127 ]). Important features characterizing them are their amorphous microstructure and unique mechanical properties. Owing to absence of dislocations, no plasticity is exhibited by BMGs. This results in very high yield strength and elastic strain limits as there is no plane for material to flow (by conventional deformation mechanisms). From a fundamental definition point of view, MG are typically different from bulk metallic glass (BMG) in that the former has fully glassy (monolithic) structure for thicknesses less than 1 mm, while the later is glassy (monolithic) is greater than 1 mm [6 , 7 ]. To date the largest BMG made in “as-cast” condition is 80 mm diameter and 85 mm in length [45 ]. There are reports of making large thin castings as casing of smart phones, but they are typically less than 1 mm [10
eBook - PDF- Subbarayan Sivasankaran, Pramoda Kumar Nayak, Ezgi Günay, Subbarayan Sivasankaran, Pramoda Kumar Nayak, Ezgi Günay(Authors)
- 2020(Publication Date)
- IntechOpen(Publisher)
61 Chapter 5 Insight into Bulk Metallic Glass Technology Development Trajectory: Mapping from Patent Information Analysis Chih-Yuan Chen Abstract Bulk Metallic Glasses (BMGs) having a completely amorphous structure possess many attractive properties, and several groups from academia and industry have conducted research to expand their application in the market. Although many efforts have focused on investigating scientific issues related to the mechanical and chemical properties of these amorphous alloys, very few studies have assessed the development trends of these amorphous materials, especially from the viewpoint of market application and R&D directions. Therefore, in this chapter, the develop-ment trajectory of BMG materials is summarized based on data extracted from patent bibliometric information. These data were used because the information on patent documents obtained from a commercial patent database, World Intellectual Property Service (WIPS 2.0), can provide the most comprehensive information on valuable R&D activities and market issues. The results summarize advances in technology based on various alloy categories and processing routes. Furthermore, the research interests are also analyzed according to different countries, companies, and research institutions. The patent information provided in this chapter can provide a clear direction to assist metallurgist/metallurgy engineers in further technology development forecasting and R&D plan management. Keywords: metastable material, bulk glass metal, bibliometrics, patent analysis, technological forecasting 1. Introduction Discovered by Klement et al. in the early 1960s, amorphous metallic glasses have attracted much attention for several decades due to their outstanding properties, such as excellent mechanical properties, good corrosion resistance, and unique physical and chemical characteristics. These metallic materials are suitable for application as a new class of advanced materials [1–3].
eBook - ePub- C. Suryanarayana, A. Inoue(Authors)
- 2017(Publication Date)
- CRC Press(Publisher)
It is probably not just one single property that is likely to be important in selecting a material (whether crystalline or glassy) for any specific application; more often than not it is a combination of a few properties. Added to this, the continuous availability and constant supply of the material, and its compatibility with the environment and the human body (if it is to be used as a replacement in the body) are also important. But, the most important aspect that a manufacturer looks for in any material is the cost involved (the cost of the material and the cost of fabrication). Unless it is less expensive than the existing competing material, it is unlikely to replace it, irrespective of the enhanced properties and performance. The only exception to this could be in some critical applications where a material is not available or an application where the cost does not play an important role, for example, in military, space, or life-saving medical applications. Succinct summaries of some of the potential applications of BMGs have recently been presented [9,10].Ashby and Greer [11] have summarized the attractive and unattractive attributes of metallic glasses and suggested that a useful starting point [12] to search for applications for these materials could be to1.Identify the attributes of the new material that are better than those of existing materials. 2.Identify the attributes that are worse. 3.Explore applications that exploit (1) and are insensitive to (2).Based on a wide-ranging comparison with conventional engineering materials, they have shown that, currently, metallic glasses are restricted to niche applications. But, due to their outstanding properties, there could be many more future applications awaiting, for example, in MEMS devices.Liquidmetal Technologies in the United States (http://www.liquidmetal.com) has already commercialized some of the BMG products [13]. Another company is BMG Corporation in Japan (http://www.bmg-japan.co.jp), which is currently manufacturing BMG samples for testing purposes.Let us now look at some of the existing and potential applications of BMG materials. These are grouped under the categories of structural, chemical, magnetic, and miscellaneous applications. 10.3Structural ApplicationsThe high yield (or fracture) strength, low Young’s modulus, large elastic strain limit, and easy formability in the supercooled liquid region are the main attributes of BMGs that make them attractive for structural applications. We will now discuss the different possible applications in this group. As mentioned earlier, the large supercooled liquid region in BMG alloys offers an excellent opportunity to form complex shapes easily. This is mainly because the plastic flow of the material in this temperature regime is Newtonian in nature (i.e., the strain rate is proportional to the applied stress). This attribute of BMG alloys has been extensively exploited to produce different types of parts with complex shapes, such as gears, coiled springs, and others. The sizes of these parts are much smaller than have been achieved using conventional crystalline alloys.
eBook - PDF- Dragica Mini?, Milica Vasi?, Dragica Minić, Milica Vasić, Dragica Minić, Milica Vasić(Authors)
- 2020(Publication Date)
- IntechOpen(Publisher)
The basic properties of different LTM-based BMGs [8]. 15 Metallic Glasses: A Revolution in Material Science DOI: http://dx.doi.org/10.5772/intechopen.90165 3. Structure, properties and applications Structure of material defines its property. BMGs do not exhibit a long-range order structure, as they solidify from liquid without reaching the crystalline ground state. However, short to medium-range structural order does develop to a consid-erable extent under the given kinetic constraints. This happens because the atoms strive to find comfortable configurations to lower their energy. The structure of the bulk metallic liquids was first observed by Bernal [9] and it was described as dense random packing. Structural features of metallic glasses are discussed by Michael et al. where the concept of efficient filling of space is supported [10]. The rational-ization of the good glass forming compositions can be possible by the analysis of dense packing. An example of simple binary metallic glass is shown in Figure 4 [10].
eBook - ePubBulk Metallic Glasses and Their Composites
Additive Manufacturing and Modeling and Simulation
- Muhammad Musaddique Ali Rafique(Author)
- 2018(Publication Date)
- Momentum Press(Publisher)
SECTION 1 B ULK M ETALLIC G LASSES AND B ULK M ETALLIC G LASS M ATRIX C OMPOSITES 1.1 METALLIC GLASSES AND Bulk Metallic Glasses/MONOLITHS Metallic glasses (MG) (Chen 1974) may be defined as “disordered atomic-scale structural arrangement of atoms formed as a result of rapid cooling of complex alloy systems directly from their melt state to below room temperature with a large undercooling and a suppressed kinetics in such a way that the supercooled state is retained/frozen” (Güntherodt 1977; Greer 1995; Inoue 1995; Johnson 1999). This results in the formation of “glassy structure.” The process is very much similar to inorganic/oxide glass formation in which large oxide molecules (silicates/borides/aluminates/sulfides and sulfates) form a regular network retained in its frozen/supercooled liquid state (Matthieu 2016). The only difference is that MGs are comprised of metallic atoms rather than inorganic metallic compounds. Their atomic arrangement is based on a mismatch of atomic size and quantity (minimally three) (Hofmann and Johnson 2010) (described in the next section), is based on short-range order (Shi and Falk 2006; Mattern et al. 2009; Jiang and Dai 2010) to medium-range order (Sheng et al. 2006; Cheng et al. 2009; Zhang et al. 2014a) or long-range disorder (Inoue and Takeuchi 2011) (unlike metals—well-defined long-range order), and can be explained by other advanced theories/mechanisms (frustration [Nelson 1983], order in disorder [Nelson 1983; Sheng et al. 2006; Ma 2015], and confusion [Greer 1993]). Important features characterizing them are their amorphous microstructure and unique mechanical properties. Owing to the absence of dislocations, no plasticity is exhibited by Bulk Metallic Glasses (BMGs). This results in very high yield strength and elastic strain limits as there is no plane for material to flow (by conventional deformation mechanisms)
- Esther Belin-ferre(Author)
- 2009(Publication Date)
- World Scientific(Publisher)
413 CHAPTER 12 DISCOVERING AND DESIGNING Bulk Metallic Glasses Srinivasa Ranganathan a , Tripti Biswas a and Anandh Subramaniam b a Department of Materials Engineering Indian Institute of Science, Bangalore, 560012, India b Department of Materials and Metallurgical Engineering Indian Institute of Technology, Kanpur, 208016 85, India E-mail: [email protected] The discovery of metallic glasses and Bulk Metallic Glasses (BMG) were important landmarks in materials research in recent times. Starting with an overview of the techniques for the synthesis of BMG, this paper will critically review the literature on glass forming criteria, glass forming compositions and structural and thermodynamic models describing glasses. With an explosion in the number of compositions forming BMG, their classification becomes important, which will help understand the relationship amongst the various BMG. Following the standard classification scheme based on compositions, Pettifor’s approach using Mendeleev number and the importance of bond orbitals in the classification of BMG is highlighted. 1. Introduction The first metallic glass alloy (Au- 25 at.% Si) was produced by Pol Duwez, 1 while developing rapid quenching techniques for chilling metallic liquids at very high rates of 10 6 K/s. Due to rapid solidification the thickness of the sample was limited to micron dimensions. Chen and Turnbull 2 showed that the samples demonstrated glass transition and thus were true glasses. The challenge of producing thick metallic glasses was met, when Kui et al . 3 produced cm thick bulk metallic glass (BMG) in Pd 40 Ni 40 P 20 alloy. Even though their paper carried the word bulk, it did not cause the excitement that came with the production of metallic glasses in bulk 414 Srinivasa Ranganathan, Tripti Biswas and Anandh Subramaniam form that came in 1988 with the discovery of Mg-Cu-Y BMG by Inoue et al .
eBook - ePub- K.H.J. Buschow(Author)
- 2013(Publication Date)
- North Holland(Publisher)
http://www.scopus.com ) also shows a large number of research papers on the subject, which indicates the intensive research activity related to such materials.Almost every year, vital papers containing scientific reports related to BMG alloys are published reporting unusual general physical, mechanical, and chemical properties. Gradual success in understanding their structure, formation mechanism, mechanical behavior, and properties leads to the creation of BMG alloys with higher performance compared to early works on this subject. For example, as a result of substantial research efforts, GFA and plasticity of BMGs have been drastically improved, increasing interest in such materials among the industrial circles. Magnetic BMG alloys developed since the mid-1990s are at present being used in various applications and this field is still expanding. BMG alloys have also become important materials for micro and nanomolding. Success achieved in the field of BMGs provides new insights in materials science offering the opportunity for further studies of these novel materials and promotes their applications.Structural materials should have high strength, fracture toughness, impact fracture toughness, and stiffness. At present, polymeric composites have started to compete in a big way with metallic crystalline alloys with regard to specific strength (the strength/mass ratio). Here, metallic glasses have a great advantage because of their high strength and specific strength. Recent achievements related to ductile Zr–Ti–Be-based crystal-glassy composites (Hofmann et al., 2008a ,b ) and the invention of Pd79 Ag3.5 P6 Si9.5 Ge2 BMG alloys with high fracture toughness (Demetriou et al., 2011 ) have inspired another set of optimistic viewpoints on metallic glasses. Moreover, although Zr–Ti–Nb–Cu–Be βZr-BMG composites show necking owing to stress-softening of the glassy phase, it was reported that Cu–Zr–Al–Co (Hofmann, 2010 ; Wu et al., 2010 ) and Cu–Zr–Al composites (Pauly et al., 2010
eBook - ePub- Sabu Thomas, Preetha Balakrishnan, M.S. Sreekala, Sreekala Meyyarappallil Sadasivan(Authors)
- 2018(Publication Date)
- Woodhead Publishing(Publisher)
Due to their superior mechanical properties, load-bearing capacity, and formability, metals are the better choice as implant materials than polymers and ceramics. However, the elastic modulus of these metals is very high compared to human bone or hard tissues. Due to this mismatch of elasticity between implant material and adjacent bone, the major part of the external load is carried by the metallic implant, leading to problems like the “stress shielding effect” [2]. Moreover, the corrosion behavior of metallic implants in body fluid also plays an important role in determining the life of the implant. As a result of corrosion, metallic implants release ions like Co, Cr, Ni, Cu, etc. to the body fluid. These ions from metallic implants can cause cancer to the biological system. Researchers investigated that the property of Bulk Metallic Glasses (BMG) can be varied with deferent composition of elements. These amorphous alloys can be engineered with lower young modulus, greater strength, and better corrosion resistance property from their crystalline counterparts and as a result these BMGs can give better response in biological system. To date, properties of several BMG systems have been investigated, such as Fe, Mg, Zn-, Ti-, etc., Among these, Ti-based BMGs have been found to be more promising candidates as biomaterial than others due to their ability to form amorphous alloy with lower elastic modulus and better corrosion resistance. However most of the Ti-based BMGs with good glass forming ability (GFA) contain toxic elements like Ni, Be, etc. A recent focus is to develop Ti-based systems for biological system which are free from those toxic elements. 12.2 Bulk metallic glass In 1974, Chen was able to prepare metallic glass rods with millimeter diameter from Pd–Cu–Si ternary alloy
eBook - PDF- Boris Ildusovich Kharisov, Oxana Vasilievna Kharissova, Ubaldo Ortiz-Mendez(Authors)
- 2016(Publication Date)
- CRC Press(Publisher)
230 Glass: Nanoglass Dhriti Ranjan Saha and Dipankar Chakravorty INTRODUCTION Nanoglass is a glassy material in which at least one of the dimensions is in the nanometer scale. Suitable techniques were used to produce glassy materials of different dimensions, for example, glassy spheres, 1D material, and 2D thin lms. Prof. Herbert Gleiter and his group initiated a work on nano- metallic glasses [1–3]. They made bulk materials by compact- ing nanometallic glass spheres. In these materials, glass–glass interfaces were formed having reduced mass density relative to the core nanospheres [2,3]. Other nanomaterials reported so far are nanodimensional silicon oxide–based glasses as 1D materials or 2D thin lms. In this chapter, we will discuss about the present status of work carried out on nanometallic and nanodimensional silica-based glasses, respectively. NANOMETALLIC GLASSES Research in bulk metallic glass (BMG) showed that they had higher strength and hardness with enhanced fracture tough- ness compared to that of the crystalline counterpart [4–7]. But they showed lower plasticity than that of crystalline systems under uniaxial tension [8]. From the literature data on mate- rials like predeformed samples and glasses with nanocrys- talline inclusion, it becomes apparent that inhomogeneous microstructure stabilizes the glass against the catastrophic failure and increases the ductility by forming multiple shear bands distributed uniformly throughout the BMG [9–12]. These shear bands improve the plasticity of the BMG by pro- moting the nucleation of secondary shear bands and prevent- ing the propagation of shear bands [9–12]. Research with an objective to improve plasticity in BMG led to the invention of using nanometallic glass systems. The study of nanometallic glass started when Jing et al. [1] reported on structurally different Pd–Fe–Si glassy spheres. They made a comparative study between nanoglass and melt-spun glass of identical composition.
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