Electron Microscopy of the Domain Structure in Ferromagnetic Metallic Glasses

1975 ◽  
Vol 33 ◽  
pp. 34-35
Author(s):  
H. J. Leamy ◽  
S. D. Ferris ◽  
D. C. Joy ◽  
H. S. Chen
Keyword(s):  
Electron Microscopy ◽  
Metallic Glass ◽  
Metallic Glasses ◽  
Liquid State ◽  
Rapid Quenching ◽  
Metallic Alloys ◽  
Subsequent Work ◽  
Lorentz Microscopy ◽  
Electron Transmission ◽  
Curie Temperatures

The formation of glassy (amorphous) metallic alloys by rapid quenching from the liquid state was discovered in 1960 (1), and subsequent work revealed that certain metallic glasses are ferromagnetic (2). Recently, transition metal based alloys, which possess Curie temperatures as high as 700°K and saturation magnetizations up to 15,000 Gauss, have been shown to be both mechanically very hard and magnetically quite soft (3). We have applied the SEM technique of Fathers et al. (4) as well as electron transmission Lorentz microscopy to a study of roller quenched (5) metallic glass ribbons of composition: TM0.75P.16X.06A1.03, where TM denotes Fe, Co, Ni, or an alloy of these and X denotes either B, C or Si (6).

Bulk Glass-Forming Metallic Alloys: Science and Technology

MRS Bulletin ◽  
1999 ◽  
Vol 24 (10) ◽  
pp. 42-56 ◽  
Author(s):  
William L. Johnson
Keyword(s):  
Metallic Glasses ◽  
Liquid Metals ◽  
Rapid Quenching ◽  
Metallic Alloys ◽  
Bulk Glass ◽  
Related Field ◽  
Glass Forming ◽  
Metallic Liquids ◽  
Potential Applications ◽  
Liquid Metal Alloy

The following article is based on the MRS Medal talk presented by William L. Johnson at the 1998 MRS Fall Meeting on December 2, 1998. The MRS Medal is awarded for a specific outstanding recent discovery or advancement that has a major impact on the progress of a materials-related field. Johnson received the honor for his development of bulk metallic glass-forming alloys, the fundamental understanding of the thermodynamics and kinetics that control glass formation and crystallization of glass-forming liquids, and the application of these materials in engineering.The development of bulk glass-forming metallic alloys has led to interesting advances in the science of liquid metals. This article begins with brief remarks about the history and background of the field, then follows with a discussion of multicomponent glass-forming alloys and deep eutectics, the chemical constitution of these new alloys, and how they differ from metallic glasses of a decade ago or earlier. Recent studies of deeply undercooled liquid alloys and the insights made possible by their exceptional stability with respect to crystallization will then be discussed. Advances in this area will be illustrated by several examples. The article then describes some of the physical and specific mechanical properties of bulk metallic glasses (BMGs), and concludes with some interesting potential applications.The first liquid-metal alloy vitrified by cooling from the molten state to the glass transition was Au-Si, as reported by Duwez at Caltech in 1960. Duwez made this discovery as a result of developing rapid quenching techniques for chilling metallic liquids at very high rates of 105–106 K/s.

scholarly journals Examining metallic glass formation in LaCe:Nb by ion implantation

2017 ◽  
Vol 32 (2) ◽  
pp. 127-135
Author(s):  
Richard Sisson ◽  
Cameron Reinhart ◽  
Paul Bridgman ◽  
Tatjana Jevremovic
Keyword(s):  
Thin Film ◽  
Electron Microscopy ◽  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Metallic Glass ◽  
Metallic Glasses ◽  
Material Characterization ◽  
Volume Distribution ◽  
Molten Metals ◽  
Fast Cooling

In order to combine niobium (Nb) with lanthanum (La) and cerium (Ce), Nb ions were deposited within a thin film of these two elements. According to the Hume-Rothery rules, these elements cannot be combined into a traditional crystalline metallic solid. The creation of an amorphous metallic glass consisting of Nb, La, and Ce is then investigated. Amorphous metallic glasses are traditionally made using fast cooling of a solution of molten metals. In this paper, we show the results of an experiment carried out to form a metallic glass by implanting 9 MeV Nb 3+ atoms into a thin film of La and Ce. Prior to implantation, the ion volume distribution is calculated by Monte Carlo simulation using the SRIM tool suite. Using multiple methods of electron microscopy and material characterization, small quantities of amorphous metallic glass are indeed identified.

Using Fluctuation Microscopy to Characterize Structural Order in Metallic Glasses

2003 ◽  
Vol 9 (6) ◽  
pp. 509-515 ◽  
Author(s):  
Jing Li ◽  
X. Gu ◽  
T.C. Hufnagel
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Resolution ◽  
Metallic Glass ◽  
Metallic Glasses ◽  
The Other ◽  
Structural Order ◽  
Transmission Electron ◽  
Medium Range ◽  
Fluctuation Microscopy

We have used fluctuation microscopy to reveal the presence of structural order on length scales of 1–2 nm in metallic glasses. We compare results of fluctuation microscopy measurements with high resolution transmission electron microscopy and electron diffraction observations on a series of metallic glass samples with differing degrees of structural order. The agreement between the fluctuation microscopy results and those of the other techniques is good. In particular, we show that the technique used to make thin specimens for electron microscopy affects the structure of the metallic glass, with ion thinning inducing more structural order than electropolishing. We also show that relatively minor changes in the composition of the alloy can have a significant effect on the medium-range order; this increased order is correlated with changes in mechanical behavior.

Effect of loading rate on crystallization of metallic glass supercooled liquids

2020 ◽  
Vol 1 (3) ◽  
pp. 18-21
Author(s):  
E. Davoodi ◽  
M. Hasan ◽  
S. Rana ◽  
G. Kumar
Keyword(s):  
Metallic Glass ◽  
Metallic Glasses ◽  
Liquid State ◽  
Loading Rate ◽  
Supercooled Liquid ◽  
Supercooled Liquids ◽  
Onset Temperature ◽  
Crystallization Time ◽  
Processing Temperature ◽  
Supercooled Liquid State

Metallic glasses exhibit unique thermoplastic processing capability, which is enabled by their metastable supercooled liquid state below the crystallization temperature. The thermoplastic processing critically depends on the crystallization time (processing time window), temperature (viscosity), applied load, and strain-rate. Among these parameters, the effects of crystallization time and processing temperature have been extensively studied. However, the effects of load and loading rate have not been thoroughly investigated. In this work, we performed a systematic study of load on the supercooled liquid state of three metallic glass formers: Pt-based, Zr-based, and Pd-based. The results show that the load-response of a metallic glass supercooled liquids is strongly composition dependent. The onset temperature of crystallization decreases with increasing load in Pt-based metallic glass whereas for Zr-based and Pd-based metallic glasses the onset temperature remains unchanged. The crystallization peak time is reduced for all three metallic glasses after thermoplastic forming. The results are discussed in terms of nucleation and growth of crystallites in metallic glasses.

Reply to the comments of Y.H. Liu: Ion sputter erosion in metallic glass—A response to “Comment on: Homogeneity of Zr64.13Cu15.75Ni10.12Al10 bulk metallic glass” by L-Y. Chen, Y-W. Zeng, Q-P. Cao, B-J. Park, Y-M. Chen, K. Hono, U. Vainio, Z-L. Zhang, U. Kaiser, X-D. Wang,and J-Z Jiang [J. Mater. Res. 24, 3116 (2009)]

2010 ◽  
Vol 25 (3) ◽  
pp. 602-604 ◽  
Author(s):  
Lian-Yi Chen ◽  
Qing-Ping Cao ◽  
J.Z. Jiang ◽  
Jing-Wei Deng
Keyword(s):  
Electron Microscopy ◽  
Metallic Glass ◽  
Bulk Metallic Glass ◽  
Metallic Glasses ◽  
Ion Beam ◽  
Ion Milling ◽  
Transmission Electron ◽  
Surface Fluctuation ◽  
Beam Parameters ◽  
Sputter Erosion

The morphology of the dark and bright regions observed by transmission electron microscopy for the Zr64.13Cu15.75Ni10.12Al10 bulk metallic glass strongly depends on the ion beam parameters used for ion milling. This indicates that the ion beam could introduce surface fluctuation to metallic glasses during ion milling.

Nanocrystallization of Cu–(Zr or Hf)–Ti metallic glasses

2002 ◽  
Vol 17 (8) ◽  
pp. 2112-2120 ◽  
Author(s):  
D. V. Louzguine ◽  
A. Inoue
Keyword(s):  
Electron Microscopy ◽  
Metallic Glass ◽  
Metallic Glasses ◽  
Energy Barrier ◽  
Low Energy ◽  
X Ray ◽  
Cubic Phases ◽  
Transmission Electron ◽  
Diffusion Controlled ◽  
And Diffusion

Crystallization of the Cu60Zr30Ti10 and Cu60Hf25Ti15 metallic glasses was studied by x-ray diffractometry, transmission electron microscopy, differential scanning and isothermal calorimetries. Metastable Cu–Zr–Ti and Cu–Hf–Ti cubic phases primarily precipitated in the Cu60Zr30Ti10 and Cu60Hf25Ti15 metallic glasses. The Cu60Zr30Ti10metallic glass crystallizes with low energy barrier for nucleation while crystallization of the Cu60Hf25Ti15 metallic glass takes place by nucleation and diffusion-controlled growth of cubic Cu–Hf–Ti phase particles with constant nucleation rate. The Cu60Hf25Ti15 metallic glass is characterized by a low activation energy for nucleation.

Formation of Glassy Spinodals in Bulk Metallic Glasses

1998 ◽  
Vol 554 ◽  
Author(s):  
W. H. Guo ◽  
C. C. Leung ◽  
H. W. Kui
Keyword(s):  
Phase Separation ◽  
Eutectic Alloy ◽  
Metallic Glasses ◽  
Liquid State ◽  
Bulk Metallic Glasses ◽  
Rapid Quenching

AbstractWhen a eutectic alloy melt is undercooled well below its liquidus T1, liquid state phase separation occurs. The liquid morphologies can be frozen by subsequent crystallization. It was found that for Pd82Si18 when rapid quenching is also employed, ore of the phase-separated liquids after solidification is amorphous. The undercooled specimen is in bulk form with a diameter of ∼ 5 mm.

Pd-Based Metallic Glass Films Formed by Electrodeposition Process

2012 ◽  
Vol 194 ◽  
pp. 183-186 ◽  
Author(s):  
Chihiro Mochizuki ◽  
Takashi Senga ◽  
Masami Shibata
Keyword(s):  
Metallic Glass ◽  
Diffraction Pattern ◽  
Metallic Glasses ◽  
Amorphous Structure ◽  
Diffraction Peak ◽  
Metallic Alloys ◽  
X Ray Diffraction ◽  
Electrodeposition Process ◽  
X Ray ◽  
Glass Films

The formation of Pd-Ni-P and Pd-Ni-Cu-P metallic glass films using the electrodeposition method was examined. In this study, the structure and composition of these metallic alloys were investigated at various condition of electrodeposition. The X-ray diffraction pattern on the electrodeposited Pd-Ni-P films in the range of 18-69 at% Pd, 12-62 at% Ni and 9-21 at% P showed a broad diffraction peak, which indicates metallic amorphous structure. A result of DSC showed that the electrodeposited Pd-Ni-P films in the range of 36-57 at% Pd, 24-47 at% Ni and 16-21 at% P were metallic glasses. In addition, it was proven that the electrodeposited Pd54Cu8Ni22P16 film was metallic glass.

TEM study of amorphization of Cu and Ti foils by cold-rolling

1990 ◽  
Vol 48 (4) ◽  
pp. 146-147
Author(s):  
W. A. Chiou ◽  
N. L. Jeon ◽  
Genbao Xu ◽  
M. Meshii
Keyword(s):  
Solid State ◽  
Cold Rolling ◽  
High Energy ◽  
Rapid Quenching ◽  
Vapor Condensation ◽  
Metallic Alloys ◽  
Solid State Reactions ◽  
High Energy Particle ◽  
Amorphous Metallic Alloys ◽  
Thin Foils

For many years amorphous metallic alloys have been prepared by rapid quenching techniques such as vapor condensation or melt quenching. Recently, solid-state reactions have shown to be an alternative for synthesizing amorphous metallic alloys. While solid-state amorphization by ball milling and high energy particle irradiation have been investigated extensively, the growth of amorphous phase by cold-rolling has been limited. This paper presents a morphological and structural study of amorphization of Cu and Ti foils by rolling.Samples of high purity Cu (99.999%) and Ti (99.99%) foils with a thickness of 0.025 mm were used as starting materials. These thin foils were cut to 5 cm (w) × 10 cm (1), and the surface was cleaned with acetone. A total of twenty alternatively stacked Cu and Ti foils were then rolled. Composite layers following each rolling pass were cleaned with acetone, cut into half and stacked together, and then rolled again.

METGLAS ALLOY 2826

Alloy Digest ◽  
1976 ◽  
Vol 25 (11) ◽  
Keyword(s):  
Magnetic Properties ◽  
Metallic Glass ◽  
Liquid State ◽  
Single Phase ◽  
Heat Treating ◽  
High Permeability ◽  
Metallic Material ◽  
Nickel Iron ◽  
Rapid Quench ◽  
Chemical Corporation

Abstract METGLAS Alloy 2826 (Fe40Ni40P14B6) is a ferromagnetic, high permeability, nickel-iron metallic glass which, when appropriately annealed, yields a material similar to the higher nickel containing permalloys in magnetic properties. Alloy 2826 is a single phase, opaque metallic material with a glass-like structure obtained by a very rapid quench from the liquid state. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as creep. It also includes information on forming and heat treating. Filing Code: Ni-235. Producer or source: Allied Chemical Corporation.

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