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With more than three decades of experience spanning automotive, aerospace and industrial innovation, Gavin Shipley, Technical Director at Sarginsons Industries, has built his career around taking ambitious engineering concepts beyond the drawing board and into scalable, commercially viable production. Today, that philosophy sits at the heart of his work on advanced lightweight aluminium casting, where simulation, digital twin technology, circularity and low-carbon manufacturing are increasingly converging. Shipley is currently leading the APC25 PIVOT programme, working alongside industry and academic partners to develop next-generation structural aluminium casting solutions.
At Sarginsons, this includes a world-first capability to virtually crash-test aluminium castings using variable mechanical properties, with the company targeting component weight reductions of up to 40 per cent while incorporating 100 per cent recycled aluminium into structural castings.
In this exclusive conversation with AL Circle, Shipley looks beyond lightweighting to explain why the next chapter of aluminium casting could be as much about design freedom, digital validation, circularity and manufacturing efficiency as reducing vehicle mass.
AL Circle: The PIVOT project has attracted attention for the impressive weight savings it achieved. But when you look back on the programme, what do you personally consider its biggest success—and was it the result itself or something the team learned along the way?
Gavin Shipley: Whilst significant lightweighting has been achieved with this project, this is only one element of our much broader approach to considering future aluminium casting development and manufacture. The PIVOT team have been working collaboratively to develop a new world-first casting design software, to demonstrate how we can move to low-carbon recycled content with advanced alloy research, and to develop new UK-based circular techniques for successfully repurposing end-of-life material.
This holistic approach has allowed for sustainability to be married with advanced lightweighting technology to offer a complete future solution, and I think this is our greatest success
AL Circle: Everyone talks about lightweighting. Are we in danger of making aluminium's value proposition too narrow?
Gavin Shipley: With the shift to electrification in the automotive industry, lightweighting with aluminium is certainly key to improving vehicle range and performance. However, I think the adoption of future cast aluminium solutions goes much further than just removing mass.
The shift to single-piece aluminium parts, including the adoption of giga-castings, has allowed part count to be reduced significantly, massively simplifying supply chains and assembly approaches and reducing vehicle build times.
Aluminium castings also offer wonderful freedom for design not possible with other materials and manufacturing processes. Through the PIVOT project, we have demonstrated that organic fully freeform designs can be manufactured with the right material in the right place. What was possible only in the world of additive manufacturing is now possible at scale with cast parts at significantly lower cost.
Aluminium is also endlessly recyclable, and – as we are demonstrating through PIVOT – can be used for even the most demanding structural crash applications. This is not greenwashing with 10 or 20 per cent secondary content; this is 100 per cent recycled, which means up to a 90 per cent CO2 reduction.
AL Circle: Automakers want lighter vehicles. Engineers want design freedom. Manufacturers want components that can actually be produced at scale. Which of these priorities creates the greatest compromise when developing cast aluminium structures?
Gavin Shipley: This is a really interesting question because each of the priorities directly influences and impacts on the others. In order to lightweight OEM’s generally look for the thinnest possible wall section, but this presents significant challenges to the foundry as it leads to rapid cooling of the liquid metal in the mould, which leads to cold shuts and poor-quality components. As a result, the wall section has to be increased across the design, which add significant mass. As a result, the thin wall, hollow casting approach is counterintuitive.
We have addressed this problem in the PIVOT project by taking a completely different approach to structural casting design. By reimagining components using informed and casting aware topology optimisation, we have been able to adopt a right material in the right place philosophy. All thin walls and other parasitic mass have been removed in favour of a much more organic design with structure placed where the stiffness and performance requirements require it. These cast sections are typically rounded and of a size that suits good liquid metal flow through the mould due to a better mass-to-surface area and massively reduced heat loss. Design freedom is maintained with the adoption of printed core solutions for the internal geometry, and the result is castings that are significantly lighter and more manufacturable than the thin wall design that were adopted before. It’s a win-win.
AL Circle: There’s a growing belief that digital twins and virtual validation will eventually replace much of the physical testing carried out today. Do you share that optimism, or do you think we're still some distance from that reality?
Gavin Shipley: I think we are still some distance from fully replacing physical testing. Digital derisking using advanced simulation techniques is certainly reducing time to market by removing the trial-and-error approach adopted previously.
OEMs should now only need to undertake one crash test as true casting performance can now be fully understood in the digital space, but there is a huge amount of data required from physical testing that informs this work.
At Sarginsons, we have over 20 years of tensile test results that inform our material databases, and as we shift from primary to secondary alloy this testing will need to continue. You cannot simulate what you have never measured.
AL Circle: Imagine a global automaker approached Sarginsons tomorrow with a blank-sheet vehicle platform. If you could redesign only one structural component using everything you've learned from PIVOT, which component would you choose, and why?
Gavin Shipley: A front or rear subframe, as these are the perfect components to show-case our new approach to structural aluminium cast solutions. Subframes are conventionally a multi-component assembly using castings, extrusions, brackets, etc. that are riveted and welded together to form a suitable structure.
Our redesign would create a single-piece cast solution which would be significantly lighter through informed topology optimisation. In addition, the one-piece approach would remove the need for multi-component sourcing and the complexities of welding and post-assembly machining.
Better still, no specialist equipment would be required for industrialisation as the part could be cast using standard low-pressure units, so adoption would be possible even for more modest volumes. Lighter, stronger, greener and lower cost. And the component would look great too!
AL Circle: If you could correct one misconception the automotive industry still holds about cast aluminium, what would it be?
Gavin Shipley: All OEMs design structural cast aluminium parts on the assumption that the material properties are homogeneous across the geometry. This couldn’t be further away from the reality, as the strength and ductility will vary significantly through the part due to factors such as cooling rate, gating design, and intermetallic formations.
The current approach of applying of base level material cards in FEA analysis tends to lead to over-engineered or poorly understood solutions that often carry unnecessary mass and are challenging for the foundry to cast.
We’ve addressed this at Sarginsons by simulating the true variable material properties resultant from the casting processes, banding and mapping onto CAE meshes, and submitting with new material cards for studies such as virtual crash. This allows our clients to understand true casting performance for the very first time, derisking the process, reducing time to market and allowing for informed lightweighting. "Traditional simulation predicts the process. We predict the performance."
AL Circle: Projects like PIVOT often demonstrate what's technically possible. The harder question is what comes next. Where do you see the biggest hurdle to wider adoption, i.e., cost, manufacturing capability, supply chains, or simply industry mindset?
Gavin Shipley: PIVOT is quite unusual in the respect that it is taking the technology and manufacturing readiness levels to industrialised levels, due to the inclusion of experts from all key areas of casting development from recycling and smelting through to Aston Martin as the OEM and route to market.
With the creation of a global casting hub at Sarginsons at project completion, it is our intention to offer services to support wider adoption of the PIVOT template, whether that be with the automotive manufacturer, a tier one, or a foundry.
If there is a biggest hurdle to adoption, I think it might be with the shift to fully recycled content for structural aluminium castings. OEM’s are cautious about specifying secondary material due to preconceptions about lower quality and material properties, and within the UK we don’t yet have the right facilities to process end-of-life material in a way that allows for it to be used as an alternative to primary ingot. We tend to shred, downgrade, and export scrap aluminium, and this approach needs to stop.
Through PIVOT, we have demonstrated how this can be done, so with the right supply chains and industry mindset, we can achieve our aims of true circularity within the UK and massively reduced embedded carbon in future solutions.
AL Circle: When historians look back at this decade of automotive engineering, what role do you think advanced aluminium casting will be remembered for playing?
Gavin Shipley: I think this decade will be remembered for creating the opportunity to think about aluminium castings differently. PIVOT has been described as the biggest step forward in casting for 30 years, as by using the latest digital twin technologies married with many years of industry data and knowledge, it is now possible to create fully derisked lightweight parts that were only thought possible by 3D printing.
The new world-first one-stop-shop casting design software that is being created by Siemens for this project will allow design engineers of the future to adopt these approaches with confidence, without having to be casting specialists.
Aligned with advanced alloy development, these new and organic designs can now be created with a fraction of the carbon associated with their predecessors. This decade really is the start of a new era for our industry.
