ICMCTF 2022 Session E1-1-TuA: Friction, Wear, Lubrication Effects, and Modeling I

Tuesday, May 24, 2022 1:40 PM in Room Town & Country B

Tuesday Afternoon

Session Abstract Book
(282KB, May 12, 2022)
Time Period TuA Sessions | Abstract Timeline | Topic E Sessions | Time Periods | Topics | ICMCTF 2022 Schedule

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1:40 PM E1-1-TuA-1 2D Transition Metal Carbide MXenes: Their Synthesis, Tunable Compositions and Mechanical Properties
Babak Anasori, Brian C. Wyatt (Indiana University-Purdue University)

Two-dimensional (2D) transition metal carbides, nitrides, and carbonitrides, known as MXenes, have evolved as competitive materials and fillers for developing composites and hybrids for different applications. MXenes are denoted by a chemical formula of Mn+1XnTx (n = 1 to 4), where M represents n+1 layers of early transition metals (groups 3 – 6 of the periodic table) which are interleaved by n layers of X, where X represents carbon or nitrogen. In addition, Tx represents surface terminations bonded to the outer M layers of MXenes, where T are generally a mixture of –O, –F, –(OH), or –Cl surface groups. MXenes are synthesized via a top-down topochemical etching of their precursor carbides and nitrides, such as MAX phases. MXene flakes have strong mechanical properties (330 ± 30 GPa and 386 ± 13 GPa for Ti3C2Tx and Nb4C3Tx, respectively), which make MXenes the stiffest solution-processable 2D nanomaterials to date. The current forty synthesized MXene compositions paired within-depth ability to control their composition and structure makes MXenes a unique family of 2D materials with unlimited number of compositions and tunable properties. In this talk, we provide an overview of different MXenes compositions, their synthesis, and MXenes’ mechanical properties and discuss the effects of MXenes’ compositions, synthesis, and processing steps on their mechanical properties.

Keywords: MXenes, 2D materials, carbides, mechanical properties, composites.

2:20 PM E1-1-TuA-3 Grain Boundary Sliding and Low Friction in BCC Metals
Michael Chandross (Sandia National Laboratories); Adam Hinkle (CCDC & CBC, Aberdeen Proving Ground); Morgan Jones, Ping Lu (Sandia National Laboratories); Nicolas Argibay (Ames Laboratory)

We show evidence of low friction in BCC metals through molecular dynamics simulations and ultra-high vacuum experiments. This is shown to be correlated with grain boundary sliding (GBS) as the primary mechanism of deformation. Specifically, when grain sizes at the sliding interface are smaller than a critical, material-dependent value (on the order of 10-30 nm), a crossover occurs from dislocation mediated plasticity and Hall-Petch strengthening to GBS and interfacial softening. Results from simulations and experiments are quantitatively compared to a new predictive model of shear strength.

Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International, Inc., for the US Department of Energy’s National Nuclear Security Administration under Con- tract No. DE-NA0003525. This work was funded by the Laboratory Directed Research and Development (LDRD) program. Any subjective views or opinions that might be expressed in the paper do not necessarily represent the views of the US Department of Energy or the United States Government.

3:00 PM E1-1-TuA-5 Evaluation of Tribocoatings in Low Viscosity Fuels
Maddox Dockins, Aditya Ayyagari, Srinivasan Srivilliputhur (University of North Texas); Stephen Berkebile (US DEVCOM Army Research Laboratory); Diana Berman, Andrey Voevodin, Samir Aouadi (University of North Texas)

M. Dockins1, A. Ayyagari1, S. Srilliviputhur1, S.P. Berkebile2, D. Berman1, A.A. Voevodin1, S.M. Aouadi1

1Department of Materials Science and Engineering, University of North Texas, Denton, TX 76203, USA

2 US DEVCOM Army Research Laboratory, Aberdeen Proving Ground, MD, United States

Degradation of sliding surfaces creates a significant problem for mechanical assemblies. In the case of next generation fuel delivery systems, steel on steel contacts in low viscosity fuel environments have been shown to experience scuffing failure after extended operation under rough conditions, as well as poor general tribological performance. To prevent this scuffing-induced failure, various surface modification techniques were implemented, such as the application of carbide- and nitride-based protective coatings via PVD and plasma spray methods. These surface modification techniques were evaluated in various fuel environments and counterbody compositions using a high frequency reciprocating rig tribometer in a sliding velocity range of 0.2 to 0.6 m/s and contact pressures ranging from 500 to 1200 MPa. Their relative performance was evaluated according to their wear rates, average coefficient of friction, and oxidation as determined via SEM/EDS. These results were explained theoretically through density functional theory calculations that quantify the effect of surface interactions with the fluid.

3:20 PM COMPLIMENTARY REFRESHMENTS IN EXHIBIT HALL
4:00 PM E1-1-TuA-8 Phototribology: Control of Friction by Light
Bruna Perotti (UCS); Antonio Cammarata (Czech Technical University in Prague, Czech Republic); Felipe Cemin (Université Paris-Saclay and UNICAMP); Saron Sales de Mello (UCS and UNICAMP); Leonardo Leidens (UCS); Fernando Echeverrigaray (UCS and UNICAMP); Tiberiu Minea (Université Paris-Saclay); Fernando Alvarez (UNICAMP); Alexandre Michels (UCS); Tomas Polcar (University of Southampton and Czech Technical University ); Carlos Figueroa (UCS)
Friction phenomenon is a complex manifestation of nature originated in energy dissipation events owing to the mechanical lost work of non-conservative forces. It is a property influenced by contact area, normal force, surface chemistry, mechanical properties, among others. There are several ways of tuning friction, all of them nonreversible processes. Thus, the active control of friction though external sources is a challenge in tribology. In this study, we report active control of friction forces at the nanoscale in TiO2 thin films (anatase) obtained by HiPIMS as a function of the presence or absence of UV radiation (λ = 365 nm and nominal power of 5 mW) by friction force microscopy (FFM). According to the effects, this phenomenon of light-matter interaction is reversible, stable, and can be tuned/controlled by UV light. The radiation incidence modifies the physicochemical interactions at the sliding interface in TiO2 thin films bringing on a dramatic reduction of frictional force of up to 61%. To understand the energy dissipation process, the characteristic frequencies of the system were analyzed; to this aim, atomic force microscopy signals were measured by wavelet analysis. The results show that the surface activation by UV light reduces the dissipated energy. Ab initio simulations were used to corroborate that the electron excitation augments the electronic density on the material surface. According to these results one can conclude that the reduction in friction is a result of the lower atomic orbital overlapping on the surface. These findings contribute to a new conceptual framework in tribology where light may be defined as a fourth body and the integration of tribology with photonics and optoelectronics providing a promising direction for applications in micro- and nano-opto-electromechanical systems. View Supplemental Document (pdf)
4:20 PM E1-1-TuA-9 Development and Evaluation of Self-Lubricating Nanocomposite Coatings for Metal Forming Dies
Jianliang Lin (Southwest Research Institute, San Antonio Texas)
Die failure in metal forming industry results in substantial losses of time and money. Conventional lubricants are widely used for die release as well as for cooling assistance on the die surface. However, lubrication is difficult at high temperatures. Oxidation and scaling occur on the work pieces that lead to poor surface finish and possible warping of the material during cooling. The aim of the research is to develop a self-lubricating nanocomposite coating system for metal forming die components and investigate the self-lubricating behavior and thermal stability of the coatings at elevated temperatures. The designed coating systems consist of a nanocomposite matrix doped with solid lubricant phases, e.g. noble metals and amorphous carbon. The composite structure offers multifunctionality, including high wear resistance, good oxidation resistance, crack resistance, and self-lubricating properties at elevated temperatures. In this study, different nanocomposite coating matrixes, e.g. TiSiCN and CrAlN, were doped with different levels of Ag. The coatings were deposited by high power impulse pulse magnetron sputtering (HiPIMS) assisted by hot filaments. The elemental composition, phase structure, microstructure, adhesion, and mechanical properties of the coatings were studied by different means. The tribological properties and self-lubricating behavior of the coatings were evaluated using a high temperature tribometer at 700 oC. The thermal stability and thermal shock resistance of the coatings were evaluated using thermal cyclic test by cycling the coatings from RT to 700 oC with a testing cycle up to 1200 cycles. The results showed that the density and adhesion of all coating systems decreased as the Ag content increased in the coatings. The lowest COF of 0.1 was achieved in the coatings at 700 oC. Excellent thermal stability and thermal shock resistance, and high temperature lubricity were observed in the coatings with an optimal Ag content.
Session Abstract Book
(282KB, May 12, 2022)
Time Period TuA Sessions | Abstract Timeline | Topic E Sessions | Time Periods | Topics | ICMCTF 2022 Schedule