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
2013
First
Understanding Rheology of Lubricants in Elastohydrodynamic Contacts by Through-Thickness Velocity Profile Measurements Dr. Janet Wong (UK)

13A08
Ⅰ. Summary
This project concerns the flow of lubricants in an EHD contact. With the financial support of TTRF and EPSRC, a novel fluorescence-based technique was implemented to examine, the through-thickness velocity profile of a model lubricant in-situ in an EHD contact. While the commonly assumed linear profile has been observed in some conditions, other profiles that indicate non-homogeneous shear flow and wall slip were also observed. This suggests that the linear Couette flow profile, which is commonly assumed from friction prediction, does not always hold. Hence care must be taken and efforts that promote better understanding of EHD lubricant rheology are necessary for accurate friction prediction.
Ⅱ. Related Publication
(Researcher doesn't agree to disclose main report.)
13A08 Related Publication (HP).pdf
Affiliation of Principal Investigator:
Imperial College London
Erosion and Sliding wear properties evaluation of the functional graded coating deposited on the CFRP using warm spray technique Dr. Ganesan Amirthan (Japan),
Prof. Masahiro Fukumoto (Japan)

13A10
Ⅰ. Summary
A thick titanium coating was deposited on carbon fiber reinforced plastics (CFRP) by a newly developed warm spray system. Three different coating morphologies were developed by varying the nitrogen flow rate in the warm spray system. A ring-on-disc tribometer was used to access the tribo-behavior of the coating. The results revealed the coatings with nitrogen flow rates of 1000 standard liter per minute (SLM) and 1250 SLM played a vital role ion wear behavior by improving the coating integrity like density and hardness. Moreover, a strain-hardening phenomenon had made the coatings have a relatively high wear resistance, which was much better than that for commercial pure titanium.
Ⅱ. Related Publication
(Researcher doesn't agree to disclose main report.)
13A10 Related Publication (HP).pdf
Affiliation of Principal Investigator:
Toyohashi University of Technology
2013
Second
Tribology Properties of β-Sheet Protein Hydrogels as Artificial Cartilage for Osteoarthritis Repair Dr. Philippa Cann (UK),
Dr. Daniele Dini (UK)

13B04
Ⅰ. Summary
Osteoarthritis (OA), due to damage of articular cartilage (AC) is the most frequent cause of disability affecting the elderly population. Research supported by the TTR Grant has examined two aspects of OA; mechanical damage and the effect on lubrication and the tribological function of artificial materials for AC repair. The mechanical quality of shear-tested AC tissue declined as a result of induced damage to the surface, suggesting that mechanical, as well as enzymatic degradation plays a role in the degradation of AC in vivo. In the second study porous silk hydrogels were tested as biomaterials for AC repair. Mechanical and friction/wear tests were carried out on the hydrogel materials and compared to porcine AC. Mechanical tests showed hydrogels had a comparable compressive modulus to AC, with stiffness improved by decreasing pore size. Shear testing showed hydrogels had a cartilage-like frictional response, dominated by interstitial fluid support and showed negligible wear.

Ⅱ. Main Report
(including Related Publication)
13B04 Main Report (HP).pdf
Affiliation of Principal Investigator:
Imperial College London
Discovering the Mechanisms of Nano-lubrication by Studying the Effect of Nanoparticle Additives on Wear Assoc. Prof. Robert L. Jackson (USA)

13B10
Ⅰ. Summary
This work investigated the tribological effects and mechanisms of nanoparticle additives on lubrication through experimental and analytical investigations on colloidal lubricants. Based on the results, the mechanism of “the reduction in area of contact” for nanoparticles in boundary and mixed lubrication was proposed. A statistical third body contact model was used along with experimental results to further verify this mechanism. The results also showed that the nanoparticles reduce the friction force in the thin film elasto-hydrodynamic lubrication (EHL) regime. In the EHL regime, the nanoparticles induce a plug flow and localize the shear to the layers adjacent to the walls which in turn reduce the friction force. The results showed that diamond nanoparticles in fully formulated oil can effectively reduce friction and impose a positive polishing effect on the surfaces. Silver nanoparticles in fully formulated oil showed significant reduction in both the friction and wear.
Ⅱ. Main Report
(including Related Publication)
13B10 Main Report (HP).pdf
Affiliation of Principal Investigator:
Auburn University