TLT: Can you tell us about your current role and responsibilities and how it relates to lubrication engineering or tribology?
Bryant: I am currently a professor of tribology and corrosion engineering at the University of Birmingham where I lead a research group focusing on how surfaces interact—covering everything from friction and wear to corrosion and their interactions. This includes biomedical materials tribocorrosion for hip, knee and spine devices, soft tribology of cellular and gel-like surfaces, triboelectrification of materials in manufacturing and electric vehicle (EV) applications, low friction 2D materials designs for nuclear/space application and non-aqueous corrosion of non-ferrous materials. 

Right now I’m pushing forward with both research and teaching in modern areas like corrosion, tribology, surface science and biomechanics. This includes everything from exploring how surface chemistry affects energy production to studying biotribology and biocorrosion and investigating ways to mitigate these effects. My team and I are all about understanding and improving how materials interfaces interact across the length-scales, particularly where complex degradation/chemical processes (e.g., wear and corrosion) occur simultaneously—it’s something that comes up in a lot of different applications but is largely not considered.

One big focus of ours, that underpins all our work, is the development of real-time testing methods, so we can see these interfacial processes as they happen. We do this using our own advance tribometer methodologies as well as whole systems-based approaches, such as hip or knee joint simulators, which use real-world components and real-world loading/motion inputs. We have applied this approach to medical devices as well as roller bearing systems. These new techniques are vital and underpin our ability to better understand how engineering systems work and innovate toward more durable and sustainable solutions. 

I have always collaborated closely with industry, other universities and regulators, including advising the UK’s Medicines and Healthcare products Regulatory Agency on tribology and corrosion related to medical devices. A lot of my work involves translating our advanced testing methods into industry standards like ISO and ASTM. 

TLT: What are some of the key challenges or trends you are currently witnessing in the field of lubrication engineering or tribology?
Bryant: Sustainability underpins all our activities—whether it’s developing longer-lasting medical devices such as joint replacements and breast implants, finding alternative protein sources for food or advancing the electrification of engineering systems. Tribology is a critical enabling technology that supports all these efforts.

Driving technological advancements with real-world societal impact requires foundational tribological science. Significant efforts are underway to develop predictive in silico models, validated by multiscale experimental techniques. These approaches are garnering significant interest, especially within medical regulatory science, where regulatory bodies are now considering computational evidence as part of the evidence portfolio required to bring a medical device to market. In this domain, tribological models remain largely semi-empirical and limited in capability to predict compound degradation/tribochemical processes. In the case of soft-tissue interactions, even less is known about the underpinning biotribological processes that underpin performance. 

Importantly, to make computational models truly effective, it is vital to improve testing processes by using sensorized instrumentation to monitor interfacial processes in real-time. My team and I are dedicating much of our effort to this area, exploring various in situ sensing modalities—such as electrochemistry for corrosion, near-interface eddy-current sensing for micro-motion sensing and acoustic emission for fracture and wear—to assess wear-corrosion interactions in real time. While real-time sensing itself isn’t new, integrating it with custom micro-tribometer models and advanced techniques like scanning probe microscopy allows us to gain deeper insights into the physical aspects of tribocorrosion systems, an area that remains largely unexplored. Our group is also among the few to integrate these methodologies into hip, knee and spine joint simulators, enabling the testing of clinically relevant implants before implantation.

These contributions support global digitization initiatives, which, when combined with formal optimization tools, have the potential to create powerful design systems. Such systems not only enhance our collective understanding but also streamline the development and translation of new innovations.

TLT: Could you share an interesting project or research you have been involved in that has had an impact on the lubricants/tribology community? 
Bryant: One of the most notable achievements has been the development of new coatings for medical devices, which have also influenced testing equipment (now sold globally by a UK company) and contributed to new ISO and ASTM methodologies. Some of this work has directly informed regulatory policies, while other aspects have helped companies bring products to market. Initially focused on hip replacements, the research has expanded over time to encompass emerging areas in joint replacements, including shoulder arthroplasty, as well as recent advancements in tissue engineering and sparing devices where we have made developments toward unifying the hotly debated boundary versus fluid-structure lubrication mechanisms. 

All of my research is grounded in the principles of sound engineering science. For instance, the in situ imaging methodologies I developed for assessing cell-device interfaces have been used in collaboration with food scientists to reveal new insights into multiphase fluid lubrication properties. Moreover, our development of low-load, high-speed tribometry methods initially applied in the 2D materials domain for aerospace applications has recently extended into particle electrification for pharmaceutical uses.

My recent work has increasingly focused on global efforts in cancer engineering. Engineering concepts such as contact mechanics, materials characterization and analytical methods are proving essential in understanding how diseases like metastatic bone disease impact bone fracture mechanics. Additionally, our research in aqueous lubrication has promising applications in this field.

TLT: In your opinion, what are some of the critical areas that require further research or development in the field of lubrication, tribology or corrosion? 
Bryant: Numerous unanswered questions remain regarding the wear-corrosion processes of implantable devices. While hip and knee replacements have generally been highly successful, challenges such as metal ion release mechanisms, metal sensitivity and nanoparticle generation continue to raise concerns. Although the “wear” of biomedical materials is often considered negligible when optimal material combinations are used, clinical issues related to friction and wear persist. Hard coatings, like diamond-like carbon (DLC) and TiN present a particularly intriguing dilemma: they perform flawlessly in laboratory settings yet exhibit unacceptably high complication rates in vivo. Additionally, many unknowns surround new manufacturing technologies, such as additive manufacturing, where the fundamental metallurgy and passivity of these novel materials differ from their bulk counterparts.

Without a doubt, aqueous lubrication will play a key role in achieving sustainability targets. If there is water available to interact with metallic or semiconductive surfaces, electrochemical corrosion processes are inevitable, meaning a purely physical approach will not address all challenges. Nature offers some impressive tribological systems that can serve as inspiration to these challenges, but significant work remains to translate current tribological science into practical engineering applications. 

TLT: How do you see the future of lubricants/tribology evolving, and what role do you think emerging technologies or advancements will play in shaping the industry?
Bryant: The future of lubricants and tribology will be profoundly shaped by various technological advancements. Emerging fields, such as engineering biology, are providing promising solutions for sustainable and ecofriendly lubricant additives for both industrial and biomedical applications. Additionally, digitalization and “tribology-in-the-loop” concepts are paving the way for adaptive tribological systems that leverage real-time monitoring, interactive lubricants and predictive performance modeling based on data.

While triboelectric nanogenerators represent a rapidly expanding area, substantial research is still required to understand the fundamentals of charge transfer mechanisms at tribological interfaces, which is directly relevant to advancements in manufacturing and e-mobility.

You can reach Michael Bryant at m.g.bryant@bham.ac.uk.