Awarded Research Themes and Reports

Note: "Affiliation" in the table is based on the day of grant. Click onto find the e-mail address of principal investigator. 

Grant Year Research Theme Principal Investigator,
Co-Investigator
(Country)
Research Content
Summary / Related Publication / Main Report
2020
First
Tribochemistry of Environmentally-Friendly Phosphonium Orthoborate Ionic Liquids Dr. Filippo Mangolini(USA)

20A03
Ⅰ. Summary
Ionic liquids (ILs) have attracted considerable attention in lubrication science in the last two decades owing to their unique physico-chemical properties (e.g., low vapor pressure, high thermal stability, low flammability), which make them suitable for applications involving extreme conditions (e.g., high temperatures, low pressures), such as those founds in tribological applications (engines, turbines, spacecrafts). Despite the scientific relevance of published studies on the topic, our understanding of the lubrication mechanism of ILs is still elusive. The project shed light on the lubrication mechanisms of a promising class of environmentally-friendly ILs, namely phosphonium-based ILs. In particular, through the use of a multi-scale, multi-technique approach, the project provided evidence for the strong dependence of the lubrication mechanism of phosphonium-based ILs on applied normal pressure, while also highlighting the effect of the anion chemistry on the surface reactivity of the ILs at elevated pressures.


Ⅱ. Related Publication
(Researcher doesn't agree to disclose main report.)
20A03 Related Publication (HP).pdf
Affiliation of Principal Investigator:
The University of Texas at Austin
Reversed-hierarchical Multiscale Analytical Approach to Elucidate Micro-contacts Separated by Liquid Nano-films Dr. William Woei Fong CHONG(Malaysia),
Prof. Hedong ZHANG(Japan)

20A08
Ⅰ. Summary
The present study develops a semi-analytical reversed-hierarchical multi-length scale computational approach to simulate nano-meter thick lubricant film being supplied/entrained into a micro-sized contact. The approach numerically solves for fluid film formation using a modified Elrod’s cavitation algorithm. At diminishing separations, analytical correlations for nano-scale force laws are established using statistical mechanics and Lennard-Jones adhesion force law, respectively. An experimental study is conducted to validate the model by comparison with frictional and lubricant film formation (i.e. sliding clearance based on Newton’s ring interpretation) for a contact lubricated by nano-meter thick non-polar PFPE. The model is demonstrated to be capable of predicting: 1) lubricant film thickness growth and 2) friction force with increasing sliding velocities, correlating well with experimental data. Thus, the model has been demonstrated to be a fundamentally viable platform to bridge the knowledge gap between microand nano-scale tribological force laws, allowing for more effective optimization of boundary lubricants.


Ⅱ. Related Publication
(Researcher doesn't agree to disclose main report.)
20A08 Related Publication (HP).pdf


Affiliation of Principal Investigator:
Universiti Teknologi Malaysia (UTM)
2020
Second
Tribology of Triboelectric Nanogenerators: Understanding how Interface Mechanics Effects Electrical Output Dr. Daniel Mulvihill(UK),
Dr. Yang Xu(USA),
Mr. Guanbo Min(UK)

20A10
Ⅰ. Summary
This project has produced two major outcomes. First, a ferroelectric-assisted high-performance triboelectric nanogenerataor has been developed based on electrospun P(VDF-TrFE) composite nanofibers with barium titanate (BTO) nanofillers. Accounting for contact pressure, the max output (Voc = 315 V & Jsc = 6.7 μA/cm2) is significantly higher than for TENGs having spin-coated P(VDF-TrFE)/BTO. It is hypothesized that electrospinning increases dipole alignment due to high applied voltages, but also aids the formation of a highly oriented crystalline β-phase via uniaxial stretching. Essentially, tribo-charge transfer is boosted due to increased surface potential owing to enhanced ferroelectric polarization. Second, the role of multi-scale surface texturing has been explored for a new type of TENG based on mica in contact with polyvinyl siloxane (PVS). PVS surfaces having a range of roughnesses were cast from a 3D printed mould. Electrical output was then correlated with surface properties.


Ⅱ. Related Publication
(Researcher doesn't agree to disclose main report.)
20A10 Related Publication (HP).pdf
Affiliation of Principal Investigator:
University of Glasgow
Development of a setup for accurate measurements of metal release rates in pin-on-disk machines for a better understanding of the dynamic interface between friction-exposed CoCrMo surfaces and protein-rich environments Assist. Prof. Yolanda Hedberg(Canada),
Assist. Prof. G. Daniel G. Langohr(Canada)

20B04
Ⅰ. Summary
This study investigated the effect of serum albumin and fibrinogen on the tribocorrosion, metal release, and corrosion properties of differently manufactured cobalt chromium molybdenum alloys. We have earlier hypothesized that protein aggregation in these physiologically relevant solutions affects the ability to accurately interpret results. This hypothesis was confirmed in this study. We were able to show the protein aggregation in mixed protein solutions, but not albumin alone, after tribocorrosion tests. The release of cobalt, chromium, and molybdenum, and especially chromium, was strongly increased in mixed protein solution in a phosphate-free buffer as compared to protein-free solution and literature data with phosphates. Reciprocal linear sliding (3 N, 1 Hz) resulted in an oxide growth, and an increase in oxidized molybdenum (indicative of a decrease in pH) in the wear track in protein-free solutions, but not protein-containing solutions. Proteins acted as lubricants in the tribocorrosion process.


Ⅱ. Related Publication
(Researcher doesn't agree to disclose main report.)
20B04 Related Publication (HP).pdf
Affiliation of Principal Investigator:
Western University