Interface-controlled creep in metallic glass composites

Kalcher, Constanze; Brink, Tobias; Rohrer, Jochen; Stukowski, Alexander; Albe, Karsten

doi:10.1016/j.actamat.2017.08.058

Cited by 20 publications

(7 citation statements)

References 65 publications

(94 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For obtaining a juvenile homogenous glass, a melt was equilibrated at 2,000 K and then quenched to the glassy state (50 K) using a cooling rate of 0.01 K ps −1 . The atomic structure of the prepared Cu 64 Zr 36 glass shows good agreement with previous studies (Ritter et al, 2011;Cheng et al, 2013;Ding et al, 2014;Zemp et al, 2015;Adjaoud and Albe, 2016;Kalcher et al, 2017b). The Cu 64 Zr 36 nanoglass was obtained by cold compaction of several glassy spheres with diameter ranging from 6 to 8 nm.…”

Section: Methodssupporting

confidence: 86%

Nanoindentation of Nanoglasses Tested by Molecular Dynamics Simulations: Influence of Structural Relaxation and Chemical Segregation on the Mechanical Response

Adjaoud

Albe

2021

Front. Mater.

Self Cite

View full text Add to dashboard Cite

We present molecular dynamics simulations of nanoindentation in order to investigate the effects of segregation and structural relaxation on the mechanical properties of Cu64Zr36 nanoglasses prepared by particle consolidation and long-time annealing. Our analysis of load-displacement curves shows that the effective elastic modulus of nanoglasses is lower than that of their homogeneous metallic glass counterpart. This is mainly because of the defective short-range order present in the glass-glass interface, but to a lesser extend due to chemical inhomogeneities. Structural relaxation obtained by long-time annealing (500 ns) at 0.8 Tg leads to a shift from a homogeneous deformation to a mix of homogeneous deformation and shear bands. The obtained hardness values of annealed nanoglass are comparable to those of homogenous glass samples, but significantly higher as compared to juvenile as-prepared nanoglass samples. The results are discussed in the context of recent nanonindentation experiments.

show abstract

Section: Methodssupporting

confidence: 86%

Nanoindentation of Nanoglasses Tested by Molecular Dynamics Simulations: Influence of Structural Relaxation and Chemical Segregation on the Mechanical Response

Adjaoud

Albe

2021

Front. Mater.

Self Cite

View full text Add to dashboard Cite

show abstract

“…This is a rather unexpected finding, as typically the introduction of rigid inclusions into a mainly viscous matrix is expected to induce a decrease of the creep rates, that is, particle hardening . Furthermore, it was shown that in the studied compositions the interface orientation has a strong contribution and thus controls the creep behavior of the B2‐CuZr/MG‐Cu 64 Zr 36 nanocomposite …”

Section: Resultsmentioning

confidence: 72%

“…Recently, it was shown in a study related to the creep behavior of nanocomposites consisting of a Cu 64 Zr 36 metallic glass matrix and dispersed B2 CuZr precipitates that an amorphous interface between the dispersed B2 CuZr (nano)particles and the C 64 Zr 36 glass matrix induces a significant increase of the creep rates of the nanocomposite . This is a rather unexpected finding, as typically the introduction of rigid inclusions into a mainly viscous matrix is expected to induce a decrease of the creep rates, that is, particle hardening .…”

Section: Resultsmentioning

confidence: 98%

Influence of SiC/Silica and Carbon/Silica Interfaces on the High‐Temperature Creep of Silicon Oxycarbide‐Based Glass Ceramics: A Case Study

et al. 2018

View full text Add to dashboard Cite

In the present study, the high-temperature creep behavior of three SiOC glass ceramics with different phase compositions are compared by the authors. All three SiOC glass ceramics have a vitreous silica matrix in common, but comprise different homogeneously dispersed phases: 1) only spherical β-SiC nanoparticles (sample denoted hereafter SiC/SiO 2 ), 2) only high-aspect ratio sp 2 -hybridized carbon (i.e., C/SiO 2 ), and 3) both phases (SiC and segregated carbon, i.e., C/SiC/SiO 2 ). Compression creep experiments are performed at temperatures in the range between 1100 and 1300 C and true stresses of 50 to 200 MPa. The determined activation energy for creep of the SiOC glass ceramics of around 700 kJ mol À1 is independent of the phase composition. A stress exponent value of approximately 2 indicates an interface-controlled deformation mechanism. All SiOC glass ceramics exhibit significantly higher creep viscosities than that of vitreous silica. Surprisingly, the spherical β-SiC nanoparticles have a higher impact on the effective creep viscosities of SiOC as compared to that of the high-aspect ratio segregated carbon phase. It is concluded that this originates from the β-SiC/silica and C/silica interfaces, which have different effects on the creep behavior of silicon oxycarbide-based glass ceramics.

show abstract

“…Indeed, this view misses important complexities, such as interactions between contact spots [68], plastic deformations due to the normal load [25,[69][70][71][72], and, as the present paper indicates, slip. This slip depends on the strength of the adhesive bond and the sharpness of the interface, and as such is subject to time-dependent phenomena such as aging [73][74][75] and interface creep [76][77][78][79]. With appropriate knowledge about the parameters of the interface, wear debris formation, surface deformation due to plasticity, and slip can now be treated quantitatively using our framework.…”

Section: Discussionmentioning

confidence: 99%

Adhesive wear mechanisms in the presence of weak interfaces: Insights from an amorphous model system

Brink

Molinari

2019

Phys. Rev. Materials

Self Cite

View full text Add to dashboard Cite

Engineering wear models are generally empirical and lack connections to the physical processes of debris generation at the nanoscale to microscale. Here, we thus analyze wear particle formation for sliding interfaces in dry contact with full and reduced adhesion. Depending on the material and interface properties and the local slopes of the surfaces, we find that colliding surface asperities can either deform plastically, form wear particles, or slip along the contact junction surface without significant damage. We propose a mechanism map as a function of material properties and local geometry, and confirm it using quasi-two-dimensional and three-dimensional molecular dynamics and finite-element simulations on an amorphous, siliconlike model material. The framework developed in the present paper conceptually ties the regimes of weak and strong interfacial adhesion together and can explain that even unlubricated sliding contacts do not necessarily lead to catastrophic wear rates. A salient result of the present paper is an analytical expression of a critical length scale, which incorporates interface properties and roughness parameters. Therefore, our findings provide a theoretical framework and a quantitative map to predict deformation mechanisms at individual contacts. In particular, contact junctions of sizes above the critical length scale contribute to the debris formation.

show abstract

Interface-controlled creep in metallic glass composites

Cited by 20 publications

References 65 publications

Nanoindentation of Nanoglasses Tested by Molecular Dynamics Simulations: Influence of Structural Relaxation and Chemical Segregation on the Mechanical Response

Nanoindentation of Nanoglasses Tested by Molecular Dynamics Simulations: Influence of Structural Relaxation and Chemical Segregation on the Mechanical Response

Influence of SiC/Silica and Carbon/Silica Interfaces on the High‐Temperature Creep of Silicon Oxycarbide‐Based Glass Ceramics: A Case Study

Adhesive wear mechanisms in the presence of weak interfaces: Insights from an amorphous model system

Contact Info

Product

Resources

About