From carbon-fiber composites to wide-bandgap semiconductors, producers are shedding kilos with out sacrificing efficiency, security, or sustainability – reworking every little thing from battery enclosures to physique buildings.
Physique buildings
Lightweighting improvements in physique buildings sometimes heart on using a number of supplies. Whereas aluminum can provide weight financial savings, its stiffness in comparison with metal means it must be carried out with the right geometry to offer it the required power.
William Morgan, Buyer Technical Providers Supervisor – Automotive Sector Tata Metal UK says, “We have now seen an enormous change in the direction of superior high-strength steels (AHSS) and totally different metal merchandise from typical ones to assist lightweighting.”
There are a number of methods metal may be optimized to cut back weight. Morgan says, “Utilizing thinner gauges of metal in non-critical areas can considerably scale back weight with out compromising power.”
Changing delicate metal with high-strength metal additionally offers weight saving however maybe one of the crucial vital advances on this space is tailor welded laser blanks. “This system can create stronger and extra environment friendly joints in metal buildings using a number of grades and sizes in a single single part, permitting for thinner and lighter elements,” Morgan says. For instance, in a door panel ring panel, the metal grade closest to the hinge may be stronger the place elevated fatigue efficiency is required, than the fabric the place the door closes the place elevated formability is required to match the design of the car structure.
Contemplating the potential for bio-based composites and notably their use in motorsports, Peter Quigley, Director at Athena Blue Innovation, says, “One of many benefits of utilizing flax primarily based physique panels in GT4 is round well being and security and crash efficiency.” Not like carbon fiber panels that turn into brittle and break into shards, Quigley explains flax primarily based composites expertise ductile failures.
Electrical motors
Maybe probably the most elementary facet of lightweighting is deciding on the suitable materials or part for the job. For Dr David Moule, Technical Specialist – Electrical Drives, Servo Drives Centre of Competence at ZF, sizing the machine for the applying is the primary strategy. “After that, it’s the design optimizations that ensure that there isn’t materials that doesn’t must be there.
“Taking an electromagnetic instance, a part and seeing if there are bits of a magnetic circuit the place there isn’t a lot flux going by means of. At that time you may probably hole out these elements of the magnetic circuit and subsequently take some weight out.”
Dr Moule suggests one other space of consideration is minimizing inactive mass that’s not contributing to the torque. He suggests higher integration is an efficient lightweighting technique. “When you convey a circuit board very near a motor you don’t then have a lot of housing across the exterior that’s taking on area and weight.”
By using mathematical algorithms or increasing the protection of 1 sensor, Dr Moule argues sensor elimination inside a product might help to cut back weight and dimension if its perform may be accomplished elsewise.
When it comes to materials use, Dr Moule says, “If there’s a materials that means that you can take away warmth from part of a machine, then which will allow you to have a machine that runs cooler and that may permit you to want much less warmth sinking elsewhere.”
Thermal administration methods
Decreasing weight in thermal administration methods depends on appropriately designed cooling channels which serve a number of functions. Thermal properties are the precedence however the elements that make up these methods also can present structural integrity or crash safety.
Providing an instance of how a light-weight thermal administration resolution could possibly be carried out, Andrew Halonen, President at Mayflower Consulting explains, “Aluminum extrusion might encompass your entire battery pack. What’s necessary right here is that it’s made as one steady piece. Voids can be utilized to switch sizzling or chilly fluid. That’s the great thing about a steady piece like aluminum extrusion, you get a leak-free path constructed into your structural half, so it brings a number of worth for structural integrity for torsion and stiffness.
“Hollows within the materials are additionally areas that have to crush and take in vitality. It’s meant to maintain that crash vitality out of the delicate battery supplies. So, there’s this total stiffness worth, there’s crush vitality worth and there’s fluid passageway.
“Aluminum has a excessive conductivity for thermal properties, so it brings a number of worth to battery enclosures, which is why it’s used throughout America, Europe and China. It’s an excellent materials for batteries and aluminum is light-weight.”
Battery enclosures
When designing battery enclosures that use composite supplies, the composite should be fastidiously chosen to make sure it has the suitable fireplace retardancy traits. The examine titled, ‘A overview of developments in synthesis, manufacturing and properties of surroundings pleasant biobased Polyfurfuryl Alcohol Resin and its Composites,’ argues the seek for environmentally pleasant and sustainable supplies in fibre-reinforced composite materials manufacturing has led to using biobased supplies.
“Biomass-derived chemical compounds, their derivatives, and their functions have turn into more and more prevalent in varied industries and processes, tremendously contributing to the aim of ecological sustainability,” the examine states. “The biobased Polyfurfuryl Alcohol (PFA) resin is certainly one of such polymeric supplies that’s gaining consideration for composite functions as a consequence of its endearing Hearth Smoke and Toxicity properties.”
SGL Carbon claims a battery case which makes use of carbon fiber-reinforced plastic may be as much as 40% lighter in comparison with aluminum or metal alternate options. The development of composites means the fiber design inside the fabric may also be optimized to create the power wanted in sure areas of the part, saving materials within the course of. This may be regarded as a hybrid materials inside the composite itself to tailor the part to its use case.
Inside elements
No materials selections are made in a vacuum, and there are a selection of extra elements to contemplate within the pursuit of lighter inside elements together with price, sustainability, recyclability, texture and look. From a weight perspective alone, Halonen says, “So far as taking weight out of plastic, it’s actually onerous [because] it’s already tremendous gentle.”
Quigley says, “I feel with interiors, one of many largest drivers is styrene emissions. One other is utilizing the suitable materials in the suitable place. One of many largest challenges, particularly in plastics, is we use 1000’s of various grades of plastics.” Having a lot of several types of supplies impacts the car’s recyclability.
Comparatively, bio primarily based composites can provide sustainability and advertising and marketing advantages. Whereas bio primarily based composites won’t have the equal power and efficiency of non-bio primarily based composites, Quigley argues inside use is right for these supplies.
In dashboard and trim functions, these composites visibly show the feel of the biomaterials and permits the upper worth materials to be on show, as carbon fiber sometimes is in sports activities automobiles, for instance.
For elements like seats, overmolding can be utilized to mix the advantages of composites and conventional injection molded thermoplastics. Quigley provides, “What that offers you is the power, stiffness and type of the composite. However the injection molding means that you can get extra intricate options, like stiffening ribs, so localized reinforcement could possibly be mounting options for meeting.”
Energy electronics
“If you consider the general electrical drive, one of many areas the place there was new supplies used is the wide-bandgap (WBG) semiconductors and the alternatives they provide,” Dr Moule says, “Wanting on the controller the place the WBG semiconductors can change lots sooner, that then means that you can scale back the scale of passive elements: the inductors, the capacitors which you’ve got within the system for native vitality storage or for filtering, sometimes these elements may be comparatively massive.
“When you push up the switching frequencies with silicon carbides (SiC) and gallium nitride (GaN), the WBG semiconductors, the sizes then come down. If the sizes come down it reduces the inactive mass, and the packaging round additionally reduces, which is nice.”
The paper ‘Purposes of broad bandgap semiconductors in electrical traction drives:
Present tendencies and future views’ concludes “By leveraging the superior electrical properties, broad bandgap-based traction drives can obtain excessive switching frequencies, higher thermal administration, and decreased energy dissipation.”
The researchers clarify, “The literature overview constantly identifies SiC semiconductors as probably the most most popular WBG machine throughout varied inverter configurations, notably as a consequence of their maturity and better breakdown voltage ranges. In distinction, GaN is extremely favored in functions involving multi-level inverters.”
Chassis elements
Discussing totally different entrance higher management arm examples, Halonen says, “The Ford F150’s is 2 elements welded metal. That is the primary approach on the planet to make this half, it’s the bottom price, just a little bit heavier, it’s had trillions of miles of success, it’s extraordinarily dependable. The lightest approach to do it could be an aluminum forging. That is the bottom weight however larger price.”
One other approach of making the identical part is to make use of metal stamped elements with glass stuffed nylon insert molding for structural rigidity. This technique has been seen in Ram pickup vehicles and Tesla automobiles. Halonen explains this combines the low price of metal with the low weight and power of the composite.
Emphasizing – which focuses on Enhancing Materials Properties of Recycled Glass Fibers By Sizing – is engaged on recycling composite supplies from the wind vitality sector to automotive. The consortium, led by Longworth, goals to introduce reclaimed fibers into automotive manufacturing in a low price, top quality and excessive yield approach.
Longworth’s Deecom technique permits resins and fibers from composites to be recovered and used once more as virgin supplies. Whereas this will increase the lifecycles and circularity of composite supplies, it may also be used to construct a sturdy provide chain inside international locations or areas by sourcing and recycling end-of-life wind vitality gear and different used composites.
Wheels
Carbon Revolution claims its carbon fiber wheels are 40% to 50% lighter than comparable aluminium wheels whereas providing the identical power. Though that is probably an enormous discount in unsprung mass, the price of carbon fiber means the wheels will most certainly solely be utilized in motorsport or on high-end automobiles.
“If it appears to be like good, do you care as a shopper whether or not it’s a metal or aluminium wheel?” says Halonen. “It relies on how a lot they cost on the markup. I feel metal and aluminum are going to dominate that area in mainstream automobiles eternally.”
Improvements in wheel development will possible unlock the lightest and most cost-effective options utilizing aluminum alloys. Volkswagen, for instance, launched non-obligatory solid wheels weighing simply 8kg on the brand new Golf R mannequin. In comparison with equal alloy wheels, the solid rims are 20% lighter, demonstrating the potential of different manufacturing strategies.
“The formidable weight goal posed a serious problem for us, because the structural stability of the wheel rim is paramount,” says Volkswagen designer, Ranbir Kalha. “It took months and lots of iterations and simulations to seek out the suitable steadiness between power and weight.”
Wiring harnesses
“Everyone knows aluminum is lighter than copper, nevertheless it comes again to particular conductivity, which is the place copper wins,” Halonen says. To match the identical conductivity make-up as copper, aluminum wire must be bigger. Since wiring is already confined to small areas, further diameter can current packaging challenges. If a producer was seeking to change wiring from copper to aluminum, Halonen advises planning early within the design course of to account for the bigger dimension.
Sumitomo Electrics argues the decrease price of aluminum alone is an incentive for OEMs to make the change to aluminum wire. Regardless of the bigger gauge required, aluminum continues to be a lighter choice. The metallic itself although doesn’t remedy the issue because it has a decrease power, develops oxide layers and suffers from galvanic corrosion.
To deal with the problems with aluminum on this utility, Sumitomo Electrics has developed an aluminum alloy for the conductor. At terminals, the corporate’s system options distinctive serrations and anti-corrosion expertise to make sure the longevity and robustness of the aluminum alloy.
Whereas lowering wiring harness weight might solely have a small influence on the car’s complete weight, choosing the lighter and cheaper resolution might have vital monetary implications for mass manufacturing.
Glazing
Polycarbonate home windows are roughly half the burden of glass, however they don’t provide a fast lightweighting choice for all functions. Presently, polycarbonate home windows see probably the most use in motorsports the place each potential optimization is explored to chop lap occasions.
Whereas polycarbonate begins out crystal clear, except it’s handled appropriately with superior coatings, it has poor scratch resistance over time. As a windscreen on a road-going automotive, the longevity and danger of scratches from common use of wipers makes polycarbonate an unsuitable resolution.
Nevertheless, for fastened facet home windows, rear windscreens, sunroofs and panoramic roofs, which can be much less prone to be scratched, the burden financial savings could possibly be large. Once more, the suitable coatings must be utilized to make sure the fabric’s UV resistance over time to stop degradation.
Corning’s Gorilla Glass is maybe probably the most sensible different to conventional automotive home windows. Its windshields are manufactured from three layers, a soda-lime glass, polyvinyl butyral and Gorilla Glass. To be used in windscreens, panoramic roofs and facet home windows, the answer is as much as 30% lighter than typical glass and as much as 50% extra sturdy towards sharp and blunt impacts. Gorilla Glass has been used on the Ford GT, Porsche 911 GT2 and GT3 RS, Jeep Gladiator and McLaren 720S.
