The Surface Engineering Leadership Forum
The newly established Surface Engineering Leadership Forum is working to promote the sector. Monitor Coatings Managing Director, Dr Bryan Allcock, and former IOM3 Materials Advisor, Dr Geoff Hale, discuss its role.
Why has mankind advanced more in the last 150 years than in the previous 10,000? Sheer numbers can explain that. During the earlier 10,000 years, humans were constantly facing existential threats in the form of food security and epidemics, in most cases finally achieving food security thanks to industrialisation and more recently, being able to prevent global pandemic-level breakouts of disease. The result of this was population explosion. It is estimated that 10,000 years ago there were around five million humans inhabiting the earth, and as little as 500 years ago there were fewer than 400 million. Today the global population is estimated to be in excess of 7.7 billion.
If we look at trends in human technological advances and achievements over time, we see that in the past 150 years mankind has developed plastics, aeroplanes, the transistor, fission power, the internet and mobile technology. One of the common threads at the heart of all this innovation is surface engineering and coatings.
Given that this year is the sesquicentennial anniversary of the Institute of Materials, Minerals and Mining, it is fitting to take a short glance back at surface engineering and coatings over the last 150 years. This article is not, however, a technical bulletin for surface engineering and advanced coatings. Many great authors have captured the essence of what has been and what is still to come in terms of coatings and associated processes.
Types of surface engineering
Surface engineering is in fact a relatively new term, first aired in the late 1970s and pioneered in the 1980s, primarily in the UK. The journal Surface Engineering was conceived by Tom Bell of Birmingham University, UK, and co-workers in 1983, which paved the way for modern use of the term.
In its simplest form, surface engineering is a discipline that combines materials science with engineering. It is generally accepted that this phrase captures all aspects of coating and associated processes, and importantly it considers the coating and the substrate in combination. It includes but is not limited to metallic, organic-polymeric, inorganic and ceramic materials, along with measurement and assessment of engineered surfaces through tribology and non-destructive testing techniques.
Surface engineering technologies generally have the purpose of altering the physical, chemical and geometrical properties of engineering material surfaces. With a huge range of coating materials, potential substrate materials and functional properties of coatings, it is very difficult to pick one particular characteristic with which to compare and contrast them all.
While in metallic and ceramic coatings it is relatively easy to determine changes in hardness as a function of depth below the surface, it is more challenging to determine similar variations for properties like internal residual elastic stress (strain), electrode potential, chemical composition, chemical bonding character, fracture toughness and Young’s modulus.
Glance to the past
Dating from prehistory and Cro-Magnon man, coatings developed slowly from artistry to technology. The decorative value of coatings prevailed well past the Renaissance period (1300-1600) but it wasn’t until after the Industrial Revolution (1760-1840) that the protective functionality of coatings emerged. Research in the field of film-formers, which converted coatings into a high-technology industry at the start of the 20th Century and the stimulation provided by the need for coatings to comply with regulations has taken us firmly into the 21st Century.
There is no doubt that surface engineering plays an enormous role in everyday life. Surface engineering and advanced coatings (SEAC) is no longer seen or portrayed simply as an enabling technology or even as a special process, and is sometimes perceived as slightly detached from the product, materials or manufacturing lifecycle. SEAC is rapidly becoming a standalone industry in its own right, an essential part of modern, high productivity, integrated manufacturing and design. We are successfully shedding the old persona of being slightly out-dated and somewhat tribal in our approach and are now re-grouping and emerging as a motivationally consolidated, focused community with collective purpose and, above all, a unified direction.
So if surface engineering has been around for so long, what has prompted such renewed passion in the industry? The simple answer is value added. The industry’s current turnover is estimated at £11.2bln effecting over £140bln in associated goods with a compound annual growth rate of over 11% - by 2025 turnover is estimated to exceed £25bln and to effect over £313bln of product. The industry directly employs over 46,000 people in more than 2,000 companies, 86% of which are SMEs, while supporting a further 150,000 jobs in the UK supply chain.
But what got us here today will not get us to where we need to be tomorrow, and the SEAC community quickly realised something had to change. The groundbreaking thermal barrier coatings of the 1970s helped deal with the significant increase in turbine entry temperature (TET) needed to improve gas turbine ability and efficiency. An innovation that helped Rolls-Royce maintain its position as a world-leading technology and capability expert in gas turbine design, fabrication and manufacture. But progress dictates that we cannot stop here and work to advance must continue.
A thermal barrier coating (TBC) is an economical and effective way to protect turbine blades. With TBCs, at constant coolant flow, the life of the blade can be increased due to reduced blade temperature. On the other hand, at the same blade temperature, TBCs enable gas temperature to increase by about 65°C, which improves gas turbine efficiency and reduces sliding friction coefficient. Currently, advanced TBCs could result in about a 150K temperature drop on turbine blades. According to estimates, British airlines could save £25mln per year on fuel costs due to application of advanced TBCs in Trent engines. In the future, TBCs will be further developed to achieve higher temperature resistance, higher environment resistance and higher reliability and durability.
Into the future
Innovations in coating development will no doubt continue to thrive. There are numerous examples of surface engineering-focused research in the UK, many industry-led and often supported through the Knowledge Transfer Network and Innovate UK. Omniphobic functional coatings, capable of repelling almost any liquid, edible coatings in pharmaceutical applications, high-temperature oxidation-resistant coatings and thin-film touch-sensitive coatings in electronic applications are just a few of the UK coatings innovations emerging from the technology landscape. What is clear, however, is the lack of focus on manufacturing capability readiness levels.
Without a world-class capability in coatings application, we will continue to face fierce competition from overseas.
The manufacturing capability readiness level (MCRL) is a measure developed in the USA to assess the maturity of manufacturing stages, similar to how technology readiness levels are used. MCRLs are quantitative measures used to assess the maturity of a given technology, component or system from a manufacturing perspective. They are used to provide decision makers at all levels with a common understanding of the relative maturity and attendant risks associated with manufacturing technologies, products, and processes being considered. Manufacturing risk identification and management must begin at the earliest stages of technology development, and continue vigorously throughout each stage of a programme’s lifecycles.
The biggest consumers by value of surface engineering are the high-value manufacturing industry sectors such as aerospace, automotive and energy. When comparing modern manufacturing philosophies, such as Industry 4.0, cyber-physical connectivity and the Industrial Internet of Things (IIoT), the surface engineering community is seen to lag behind other sectors, including additive manufacturing.
The Surface Engineering Leadership Forum (SELF) was established in late 2018 to help meet the challenges of modern surface engineering by helping to build a robust and resilient ecosystem capable of sustaining rapid future growth and increased productivity.
SELF intends to address the imbalance in manufacturing readiness levels and is leading the industry through a move towards digital manufacturing via the transformational change programme. This initiative describes the journey starting from Match Fit, where a present-day coatings manufacture has engaged with modern manufacturing principles, primarily in order to:
- Reduce waste – lowering the amount of materials, capacity and manpower wasted in the process by producing just enough product to meet current demand
- Maintain quality – devise more effective manufacturing methods in order to continue making quality products despite strict reductions of waste, and
- Accelerate production – decrease the amount of time needed to manufacture product, making up for the lack of surplus.
The second stage of the journey describes Best in Class, where the coatings manufacturer has effectively plugged the digital gap. This stage demonstrates a high degree of cyber-physical integration and the cost barriers, issues of network infrastructure and maintenance associated with the adoption of the IIoT have been overcome. The final stage of the journey is World Class. This is where design for manufacture is an integral part of the surface engineer’s value chain.
Beyond the surface
Recognised by the government as one of the 22 enabling technologies required to meet the UK Industrial Strategy Grand Challenges, surface engineering and advanced coatings is an important and integral part of everyday life. The UK still heralds as a world innovator in coating development, however, the gap in the industry’s ability to deliver modern manufactured coatings continues to widen.
The Surface Engineering Leadership Forum has been established to help deliver a strong, robust and resilient ecosystem for the surface engineering and coatings community, which is key to rapid growth. This journey is mapped out through the Transformational Change.
For more information on modern surface engineering and advanced coatings, please contact Surface Engineering Association SELF Chair, Dave Elliott, at firstname.lastname@example.org, or Institute of Materials Finishing Vice-Chair, Graham Armstrong, at email@example.com.
The authors would like to thank Professors Allan Matthews and David Rickerby for their contributions and advice in preparing this article.