Effects of partial crystallization on compression and fatigue behavior of Zr-based bulk metallic glasses

2007 ◽  
Vol 22 (2) ◽  
pp. 493-500 ◽  
Author(s):  
G.Y. Wang ◽  
P.K. Liaw ◽  
Y. Yokoyama ◽  
M. Freels ◽  
R.A. Buchanan ◽  
...  

Zr50Cu40Al10, Zr50Cu30Al10Ni10, and Zr50Cu37Al10Pd3 (in at.%) are bulk metallic glasses (BMGs) with partial crystallization that were characterized by x-ray diffraction (XRD). The study of mechanical properties was conducted in compression at room temperature. Four-point-bend fatigue experiments were performed on the zirconium (Zr)-based BMGs in air. Under compressive loading, after the elastic deformation, no obvious plasticity occurred before the final shear fracture. The compression strengths are comparable to those of fully amorphous alloys. However, the fatigue-endurance limits of these BMGs were much lower than those of fully amorphous alloys. These results suggested that the fatigue behavior of a BMG is very sensitive to the microstructure, while the compression strength is not.

2020 ◽  
Vol 19 (1) ◽  
pp. 67-71
Author(s):  
Mircea Vodă ◽  
Cosmin Codrean ◽  
Viorel Aurel Şerban ◽  
Dacian Toṣa ◽  
Eugen Zặbavặ ◽  
...  

The dual amorphous phase bulk metallic glasses (DAPBMGs) contain two distinct amorphous alloys in order to bring together all the favorable properties of each phase. A viable method for obtaining dual bulk amorphous alloys is powder metallurgy. A Zr/Fe DAPBMG were successfully prepared by hot-pressing of Zr –based and Fe –based glassy alloy powder in different volumetric proportions. The samples obtained were structural investigated by scanning electron microscopy and X-Ray diffraction. Magnetic properties were determined using hysteresis graph of integrator fluxmeter type. It was found that with increasing the volume ratio of the Fe-based alloy decreases the coercivity and increases saturation magnetization


Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2815
Author(s):  
Yu Hang Yang ◽  
Jun Yi ◽  
Na Yang ◽  
Wen Liang ◽  
Hao Ran Huang ◽  
...  

Bulk metallic glasses have application potential in engineering structures due to their exceptional strength and fracture toughness. Their fatigue resistance is very important for the application as well. We report the tension-tension fatigue damage behavior of a Zr61Ti2Cu25Al12 bulk metallic glass, which has the highest fracture toughness among BMGs. The Zr61Ti2Cu25Al12 glass exhibits a tension-tension fatigue endurance limit of 195 MPa, which is higher than that of high-toughness steels. The fracture morphology of the specimens depends on the applied stress amplitude. We found flocks of shear bands, which were perpendicular to the loading direction, on the surface of the fatigue test specimens with stress amplitude higher than the fatigue limit of the glass. The fatigue cracking of the glass initiated from a shear band in a shear band flock. Our work demonstrated that the Zr61Ti2Cu25Al12 glass is a competitive structural material and shed light on improving the fatigue resistance of bulk metallic glasses.


Metals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 729
Author(s):  
Junhyub Jeon ◽  
Namhyuk Seo ◽  
Hwi-Jun Kim ◽  
Min-Ha Lee ◽  
Hyun-Kyu Lim ◽  
...  

Fe-based bulk metallic glasses (BMGs) are a unique class of materials that are attracting attention in a wide variety of applications owing to their physical properties. Several studies have investigated and designed the relationships between alloy composition and thermal properties of BMGs using an artificial neural network (ANN). The limitation of the wide-scale use of these models is that the required composition is yet to be found despite numerous case studies. To address this issue, we trained an ANN to design Fe-based BMGs that predict the thermal properties. Models were trained using only the composition of the alloy as input and were created from a database of more than 150 experimental data of Fe-based BMGs from relevant literature. We adopted these ANN models to design BMGs with thermal properties to satisfy the intended purpose using particle swarm optimization. A melt spinner was employed to fabricate the designed alloys. X-ray diffraction and differential thermal analysis tests were used to evaluate the specimens.


2007 ◽  
Vol 15 (5-6) ◽  
pp. 663-667 ◽  
Author(s):  
G.Y. Wang ◽  
P.K. Liaw ◽  
Y. Yokoyama ◽  
A. Peker ◽  
W.H. Peter ◽  
...  

2008 ◽  
Vol 604-605 ◽  
pp. 229-238
Author(s):  
Marcello Baricco ◽  
Tanya A. Başer ◽  
Gianluca Fiore ◽  
Rafael Piccin ◽  
Marta Satta ◽  
...  

Rapid quenching techniques have been successfully applied since long time for the preparation of metallic glasses in ribbon form. Only in the recent years, the research activity addressed towards the synthesis of bulk metallic glasses (BMG), in form of ingots with a few millimetres in thickness. These materials can be obtained by casting techniques only for selected alloy compositions, characterised by a particularly high glass-forming tendency. Bulk amorphous alloys are characterised by a low modulus of elasticity and high yielding stress. The usual idea is that amorphous alloys undergo work softening and that deformation is concentrated in shear bands, which might be subjected to geometrical constraints, resulting in a substantial increase in hardness and wear resistance. The mechanical properties can be further improved by crystallisation. In fact, shear bands movement can be contrasted by incorporating a second phase in the material, which may be produced directly by controlled crystallisation. Soft magnetic properties have been obtained in Fe-based systems and they are strongly related to small variations in the microstructure, ranging from a fully amorphous phase to nanocrystalline phases with different crystal size. The high thermal stability of bulk metallic glasses makes possible the compression and shaping processes in the temperature range between glass transition and crystallisation. Aim of this paper is to present recent results on glass formation and properties of bulk metallic glasses with various compositions. Examples will be reported on Zr, Fe, Mg and Pd-based materials, focussing on mechanical and magnetic properties.


2016 ◽  
Vol 61 (2) ◽  
pp. 807-810 ◽  
Author(s):  
R. Nowosielski ◽  
K. Cesarz-Andraczke ◽  
P. Sakiewicz ◽  
A. Maciej ◽  
A. Jakóbik-Kolon ◽  
...  

Abstract The aim of this paper was to investigate the corrosion resistance of Mg66Zn30Ca4 and Mg68Zn28Ca4 metallic glasses and evaluate the ability of this amorphous alloy use for medical applications as biodegradable medical implants. Taking into account the amount of Mg, Zn, Ca elements dissolved in multielectrolyte physiological fluid (MPF) from Mg66+xZn30-xCa4 (x=0.2) alloys the daily dose of evolved ions from alloys components was determined. Additional goal of the paper was determination of corrosion rate (Vcorr) and amount of hydrogen evolved from amorphous magnesium alloys in simulated environment of human body fluids during 24h immersion and during electrochemical tests. Corrosion studies were done in the multielectrolyte physiological fluid (MPF) at 37°C. The amount of hydrogen evolved [ml/cm2] and corrosion rate Vcorr [mm/year] of amorphous Mg66Zn30Ca4 and Mg68Zn28Ca4 alloys were compared. The work also presents characterization of Mg-based bulk metallic glasses structure in the form of 2 mm thickness plates. Samples structure was analyzed by means of X-ray diffraction. Fracture and surface morphology of magnesium alloy samples were identified using scanning electron microscopy.


2012 ◽  
Vol 43 (5) ◽  
pp. 1558-1563 ◽  
Author(s):  
J. Bednarcik ◽  
L. Y. Chen ◽  
X. D. Wang ◽  
J. Z. Jiang ◽  
H. Franz

Complexity ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-7
Author(s):  
Shaowen Yao ◽  
Zhibo Cheng

Based on previous experimental results of the plastic dynamic analysis of metallic glasses upon compressive loading, a dynamical model is proposed. This model includes the sliding speed of shear bands in the plastically strained metallic glasses, the shear resistance of shear bands, the internal friction resulting from plastic deformation, and the influences from the testing machine. This model analysis quantitatively predicts that the loading rate can influence the transition of the plastic dynamics in metallic glasses from chaotic (low loading rate range) to stable behavior (high loading rate range), which is consistent with the previous experimental results on the compression tests of a Cu50Zr45Ti5 metallic glass. Moreover, we investigate the existence of a nonconstant periodic solution for plastic dynamical model of bulk metallic glasses by using Manásevich–Mawhin continuation theorem.


Sign in / Sign up

Export Citation Format

Share Document