TLT: What made you get into tribology, and how long have you been working in this area? 
Notay: I’ve been fortunate to be working in the tribology area for more than 12 years now. My passion for tribology started to grow during my undergraduate studies at the University of Leeds specifically when working with STLE members professor Martin Priest and Dr. Peter Lee (now at University of Bradford and Southwest Research Institute, respectively) during a summer interim placement working on improving a top piston ring zone oil sampling technique on an internal combustion engine. I got a really good handle on not just tribology research in general, but the placement really gave me an opportunity to understand tribology in a practical sense. This furthered into additional summer placements and tribology undergraduate projects with the academics.

I then went on to complete a doctorate in engine tribology tasked at measuring piston ring pack oil film thickness using laser induced fluorescence. The system I developed allowed understanding of how lubricant degradation affects the friction and wear and ultimately impacts fuel economy, exhaust emissions, engine life and lubricant service drain intervals. I also was able to evaluate lubricant residence time in the piston ring pack. This was crucial knowledge at the time of my doctoral studies as Stop-Start engine technology was new technology designed to reduce vehicle emissions, and there were concerns with oil availability on engine restarts. My doctoral studies opened up the broader tribology field to me, and my doctorate was heavily practical-reliant, which allowed me to enhance many of my mechanical engineering skills and even some electronic control skills.

Following my doctoral studies, I worked as a tribologist at Millers Oils Ltd., a small oil blending manufacturer in the UK, for two-and-a-half years and was responsible for developing the scientific tribology knowledge underpinning the performance of low friction lubricants. Here, I learned much about the “liquid gold stuff” from a formulation standpoint and the specific industry tests required to confirm an oil for performance specifications. I am currently working for The Lubrizol Corp. as a tribologist in the Strategic Research division, pushing Lubrizol forward in tribology research activities, underpinning in-depth scientific insights with technical rigor for future product needs and new business opportunities. 

TLT: What are some of the benefits and challenges you faced when transitioning from academia to industry?
Notay: The one thing I noticed moving from the academic world was that the industry is fast paced, and the steep technology advances in transportation over the past few years have really tested each industry involved in this sector to try and keep ahead. This can impact research interests as there is a need to remember business value, and you have to balance longer term research with shorter term tactical problem solving. In academia, generally the research focus is many years ahead, and, as a result, the research can be explored much more freely. The two areas of research, academic and industry, have the same goal in terms of improving knowledge and understanding—however the timelines are different. I have, however, had the opportunity to travel (much before the COVID-19 pandemic) and widen my network group, and I represented Lubrizol in many industry groups. I have the ability to work on a diverse range of applications and challenges, such as improving efficiency and durability in engine valvetrain systems when using ultra-low viscosity fluids to solving micropitting wear phenomena in industrial gear applications. Working in industry has really opened my horizons and opportunities and brought a clearer understanding that what I do on a daily basis impacts the world from a sustainability standpoint through better tribology research.

TLT: What are some of the trends affecting the lubricant industry?
Notay: We are fortunate to be at an exciting time full of many challenges and opportunities! The quest for global carbon neutrality has driven many of our technology trends. This has driven research into how lubricants are produced from a carbon footprint and handprint, and with a focus on how global resources expect to see future chemical regulations, which might then impact lubricant formulations. The rise of vehicle electrification has brought forward new lubricant challenges as the fluid is now interacting with much more electronic equipment so copper corrosion and durability need to be balanced. Expect to see alternative fuels derived from low or zero carbon emitting energy vectors. Other exciting areas include digitization, which has really taken off recently with advancements in how we use data, and reliance on artificial intelligence and machine learning to help predict application performance outcomes. 

TLT: Given those trends, what are the future challenges and opportunities for tribological research that excite you?
Notay: Using transportation as the basis of my answer here, with the drive toward global decarbonization, there will be more reliance on using energy sources that are renewable and “green” with zero emissions to the environment. Hydrogen is one fuel that, if produced through electrolysis, can provide this, and there are some heavy-duty internal combustion engine applications currently in the world that are dual-fuelled and powered with diesel and hydrogen fuel. If successful, we could see 100% hydrogen in such applications, and this may bring new tribological challenges. Moving to complete gas medium fuels brings very little if any lubricant benefit between components in relative motion, so there could be an increase in wear in some engine components.

Other concerns could be the rise of hydrogen embrittlement. This could be some of the challenges in the future. Other challenges potentially upcoming in the short term for the internal combustion engine are generally heat related. There is a consistent drive to increased efficiency, and this may be achieved through increased brake thermal efficiency by using e-boosting and waste hear recovery systems. The additional heat that’s brought forward in these technologies will exercise the lubricant that’s protecting the mechanical components and may lead to durability concerns, especially if the oil film thickness reduces and the tribological contacts are pushed more into the boundary regime. The use of coated components in conjunction with novel lubricants could be the key to maintain durability here. The rise of electrification has brought forward new electronic hardware that interacts with the lubricant, especially the lubricant seen in the transmission system, and this has brought forward material compatibility concerns as mentioned above.

Additional tribology areas with a focus on electric vehicles are high speed motors and the durability of the bearings and lubricant aeration concerns at high speeds. Other superficial challenges are noise, vibration and harshness (NVH). It’s always been there, but since electric vehicles are much quieter than their internal combustion engine counterparts, lubricated components to improve NVH (and hence quietness) could be an area for advancement. As mentioned above, technology is advancing at an alarming rate, more than the industry can keep up from a practical sense, and I can see there being use for advanced computer modeling as a means to help understand tribological challenges so they can be tackled before they become a widespread problem.

TLT: Do you see simulations having a place in the development of lubricant formulations? 
Notay: We are seeing some good advancements in this research field especially from a mechano-chemistry standpoint, but it’s not quite there yet with the simulation technology. There is some single additive modeling that has been completed by some of the universities, and this is a step in the right direction, but lubricants are a cocktail mix of other additives that are surface competing. Taking zinc dithiophosphate (ZDDP) antiwear chemistry as an example; in a tribological contact, you have the mechanical effects of the tribocontact that provide additional heating that help drive glassy phosphorous films to form on the surface and allow it to protect the surface, and if you increase the mechanical action/energy, you can remove those films faster than they are chemical formed—and that can lead to mechanical component wear. In words, this is easy to say, but in terms of computer simulation, this is very hard to replicate. This becomes extremely convoluted when you consider in a fully formulated lubricant, the rate at which ZDDP forms on the surface is dictated by the chemical mix. I believe simulation can be developed really well when the experimental information is fed appropriately into the modeling technique so they need to work together and not as two separate research directions.

TLT: What does the future look like for young professionals who want to start their career in this industry?
Notay: The future looks bright, and although we are living in a time where there are many challenges, there are an equal number of opportunities. Being technically curious will drive research and solutions in the right direction. I encourage young professionals to drive their own future, be inspired and enjoy it as they flourish.

You can reach Dr. Rai Singh Notay at Rai.Notay@lubrizol.com.