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Formula for success The development of electrified transmission fluids can not only enhance electric vehicle performance but also help unlock the power of innovative new motor designs The interface between mechanical parts and fluid is a complex environment. Lubricant technology is a specialist area that requires a deep understanding of both chemistry and engineering, and the demands of electrified vehicles are driving this technology forwards. “For a lubricant to achieve all the tasks demanded of it, it needs to be boosted with chemical additives, each designed to perform a particular task,” says Dr Susie Hurley, senior R&D advisor at additive company Afton Chemical. “For example, transmissions need anti-wear and extreme pressure agents to protect gears and bearings. In clutches and synchronizers, friction modifiers ensure smooth and consistent engagement. And corrosion protection, for a wide range of materials, is managed using compounds that pacify more aggressive chemistries.” Performance in any one of these areas is relatively straightforward. Creating a balanced fluid that consistently delivers all of the above is where things become challenging. At the heart of this challenge is the limited surface area, as it is finite, and many properties critical for lubricant performance are achieved by additive chemistries designed to interact at the surface of mechanical parts. “Working within such a limited area effectively creates competition between additives,” explains Dr Hurley. “Adding more of one additive to boost one area of performance isn’t a simple fix; it can displace another essential component.” Additive companies are uniquely positioned to ensure that this surface competition is a fair fight. Although, the true value of an additive company lies not simply in
A fl uid with equivalent viscosity and base oil quality can show very different performance with different lubricant additive formulation
manufacturing chemicals, but performance to make it possible for a mechanical system to meet targeted performance specifications. “You’ll get maximum value from an additive company when it can work closely with the OEM and lubricant marketer to define performance needs from early in the design process; to identify and overcome challenges and design and carry out appropriate testing. That’s the best way to formulate an effective solution,” says Dr Hurley. Optimizing a lubricant can have a profound impact on the capability of the whole system. The example data (pictured) shows how formulation changes can enhance gear protection without compromising
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on the protection of other parts. The right fluid can improve the performance of existing hardware or, more excitingly, help unlock the power of innovative new designs. Never has this been truer than now, as transmission fluid development extends rapidly to include the needs of hybrid or electric vehicles. “Directly applying lubricants to electric motors has added new performance demands that call for even greater understanding and formulation skill,” says Dr Hurley. “Achieving electrical properties, enhanced cooling at lower viscosities and compatibility with new materials, all without compromising protection, has
been challenging for traditional lubricants. A new approach to formulation, focused on extending the performance of hybrid and electric vehicles, has resulted in the advent of electrified transmission fluids, or ETF.” With a greater number of additives vying for space at the surface, competition between them will only intensify. However, a good understanding of those additives and surfaces, at the earliest possible stage of development, can still ensure a fair fight and deliver balanced performance. FREE READER INQUIRY SERVICE To learn more about Afton Chemical, visit: www.magupdate.co.uk/PEHV