S REPAIRABILITY RESEARCH ustainability is a balancing act for the automotive industry. Important decisions often carry challenging trade-offs – especially during the transition to electric vehicles. Electrification offers a fast solution for curbing tailpipe emissions but, with more carbon embedded during production, the lifespan and energy efficiency of these vehicles are critical. As structures, materials and manufacturing processes change, there are growing concerns about how this might affect crash repairs. “Vehicle production is very carbon intensive, so the longer you keep a vehicle on the road the more sustainable it is,” says Bertrand Rakoto, director and global automotive practice leader at consultancy Ducker Carlisle. “I think manufacturers have a sustainability and financial responsibility to make sure that cars can be maintained – most are very cautious about that.” Safety and efficiency demands have already pushed OEMs to introduce materials including aluminum and high-strength steels that require differing bonding techniques, and Rakoto believes there’s more to come. The sector is still working toward a ‘best compromise’ for EV platforms, he says, conscious of changing technology and a need to drive down manufacturing costs. In some cases, this has involved rethinking decades-old norms – both at the factory and during repairs. Gigacasting (or megacasting) has become a hot topic within that process, replacing multiple pressed and welded steel elements with large structural sections cast from an aluminum alloy. The Tesla Model Y was a headline-grabbing early adopter, but Nio, Xpeng and Geely have also launched models with gigacast sections. Toyota will follow suit in 2026 and others are hinting that they will do the same. However, that enthusiasm isn’t universal: Fisker CEO Henrik Fisker told 2023’s Reuters Automotive Europe conference in Munich that gigacasting increases the risk of vehicles needing expensive repairs or becoming a total loss after minor collisions. That viewpoint is echoed in a recent white paper published by Ducker Carlisle’s automotive and transportation team, which suggested that the castings’ ‘below-average’ repairability could result in cheaper but more disposable vehicles. Rakoto, one of the report’s authors, says there are unknowns to address: “The repairability of megacasting is an open topic. If the casting breaks because those parts won’t bend, what is the force of the impact and would a vehicle that doesn’t use megacasting survive the same scenario? We don’t have an answer for that. We would need to take 20 Teslas with megacastings and 20 without, crash them 20 different ways and see how they compare. “The second point is, if you want to repair a megacasting, then you cut off a piece and weld, rivet or bond a new part. This [repair] part can’t come from the same die – you need new designs. You need to design the part to be repairable from the get-go, which is not really the case at the moment.” Beyond repair While many auto makers have chosen to use gigacasting for its various benefits, gigacast parts can be very costly to repair Insurance companies are watching closely. The UK’s Association of British Insurers says claims costs reached record highs last year, fueled by the rising cost of parts and workshops and therefore more expensive repairs. Darren Bright (far right), principal engineer of automotive repair at Thatcham Research – an insurance industry-funded body studying safe, sustainable repairs – says his organization’s members are keen to understand whether gigacasting might accelerate that trend. The organization began researching gigacasting last year, enabled by Tesla making parts and repair manuals available outside its approved repair network. This enabled Thatcham Research to buy the rear structure “You need to design the part to be repairable from the get-go, which is not really the case at the moment” Bertrand Rakoto, director and global automotive practice leader, Ducker Carlisle 52 MARCH 2024 www.AutomotiveTestingTechnologyInternational.com