捷豹路虎（JLR）下定决心要大刀阔斧研究汽车节能方案，Wolfgang Epple博士，JLR公司研发总监，向记者表示： “我们正试图通过在车辆上使用新兴技术来进一步减轻汽车的自身重量，譬如使用碳纤维亚麻混合材料。”

JLR正着力推进一项大胆的汽车电气化策略，Epple博士认为，如果要将CO₂ 平均排放量降到100g/km (56 mpg)以下，对于高端汽车制造商来说，电气化方案将是必由之路。如果仅仅是想单靠“混合动力及电池动力系统”来提高燃油经济性是远远不够的，但他也强调，JLR正在与12家技术合作伙伴联合开发“Evoque-e”项目，其中全新独特的高性能、模块化设计的电动电机是其研究项目之一。

CARBIO碳纤维/亚麻混合材料

Epple强调，为了减少阻力系数、摩擦、电气以及加热、制冷和通风系统所产生的寄生损失，必须运用来自不同领域的技术，制定一套完整的解决方案，同时也需要运用创新手段来减轻车辆自身重量。亚麻、碳纤维正是我们所要寻找的新材料。

Simon Black，JLR车身高级经理、Epple博士团队成员，“CARBIO项目通过运用环保腰果油树脂将碳纤维层和亚麻层结合在一起。我们之所以选择亚麻是因为其吸音的固有属性。CARBIO材料结合了碳纤维的坚韧性和轻量化优势，以及亚麻材料的可持续性和低成本优势。虽然CARBIO材料的制造成本与常规的碳纤维材料持平，但材料成本却可以降低三分之一。”

CARBIO材料制成的部件比铝制轻28%，比钢制轻55%。Black指出，得益于CARBIO的优异的NVH属性，因此可以减少隔音材料的使用。

甚至是一些不能减重的材料，也可以通过LANDS（轻量化和噪声）研究项目降低用量，LANDS项目旨在研究新型NVH材料用量削减方法的研发工作。其中一种方法是，利用回收的塑料，与通过糖精制工艺制造的填充物结合。用这种方法生产的轮拱内衬原型比现用的典型样式轻9%，但降噪效果却几乎相同。

针对那些不能减重的材料，我们也可以通过LANDS项目(轻量化与噪声)通过使用新型NVH

材料来减少其用量。其中一种方法是，利用回收塑料填充制糖过程中产生的副产物。使用这种方法生产的轮拱内衬比现有产品轻9%，但降噪效果却几乎相同。

CARBIO项目选用Composites Evolution公司的Biotex Flax亚麻材料，打造了一款碳纤维/亚麻混合材料车顶。除了其减振属性外，亚麻纤维可再生、成本低，而且还是一种碳中和材料。相较于合成环氧树脂，由腰果壳液（CNSL）制成的生物环氧树脂的坚韧性、减振性和可持续性更卓越。

在这种混合生物复合材料中，碳纤维和亚麻成分各占一半，Composites Evolution公司提供Biotex Flax亚麻材料，并由SHD Composite Materials公司预浸，该材料为实现项目目标作出重大贡献。该混合生物复合材料的抗弯刚度与碳纤维材料相仿，但成本低15%，重量轻7%，减振效果则提高了58%。

采用该材料的车顶原型由德尔塔汽车运动公司（Delta Motorsport）设计，由KS Composites公司制造。CARBIO项目获得了Innovate U.K.（英国政府创新机构）的部分赞助，克兰菲尔德大学也是该研究项目的合作方之一。

PLACES高效碳座椅的高级轻量化架构项目

Varcity是JLR涉足的另一项重大项目，旨在评估如何将碳纤维材料融合到现用的混合材料策略中，以便打造出NVH性能更优良的车身结构，且优于现行的碳纤维应用效果。项目的目标是，与铝制白车身相比减重20%。

为了能达到与铝制白车身相比减重20%的目标，JLR开展了另一项重大项目名为Varcity。主要目的在于为了提升现有碳纤维材料的NVH属性，寻求将碳纤维融合到现有的车身架构混合材料中之策略。

“Varcity项目始于捷豹C-X75概念车，”Black表示。“这款车的车身采用了非热压成型技术，适合

极薄的印刷电路板有望替代车辆的线束及电子元件，达到车辆减重的目的。就以路虎揽胜为例，车辆线路总长6000米，重约94KG。

Black表示，使用热塑性材料生产的座椅结构的轻量化道路更为有前途，经PLACES(高效碳座椅的高级轻量化架)项目重新设计的座椅，比传统钢制结构轻了30%，但丝毫其不影响舒适性。

为了达到强化该结构件的目标，生产运用了热塑性复合材料冲压成型工艺。

探索新型电机架构

JLR执管理团队正在尝试通过红外线反射玻璃等技术，打造一个“气泡”，用其来达到调控车内温度的作用。

JLR同时还在尝试运用红外面板，仅仅在有人的特定空间内加热，以此来降低能耗。从先前的测试中我们显示，该技术比的能耗仅为目前空调系统8-12kW的一半。

虽然这些研究都很重要，但动力总成仍是JLR独一无二的节能重心。JLR低碳汽车首席技术专家Mike Richardson表示，Evoque-e合作研发项目（有12个合作伙伴，由Innovate U.K.资助部分经费）旨在探索2020年之后的解决方案，内容涉及先进电气动力总成技术的所有方面。其中的关键领域之一是研发新的电机架构。

虽然先前的提供的科研项目都重要，但是动力总成才是JLR科研项目的重中之重。Mike Richardson，JLR低碳汽车首席技术专家表示，Evoque-e合作项目立项目标便是超越2020年，探索先进电气化动力总成技术各个方面，其核心之一就是开发新型电机架构。

“辐射通量电机(radial flux machines)是该项目的核心技术，该款电机体积小、重量轻，但动力非常强劲，”Richardson表示。“其功率和扭矩达到目前市面量产技术两倍，该电机采用了模块化设计，可以满足各种车型的规模化生产，并与未来常见的通用部件与系统相兼容。”

新电机还有一项环保优势：“对于那些不需要极致性能要求的应用，我们使用稀土钕磁替代铁基铁氧磁铁，用铜线圈替代铝线圈。”他表示，这样的配置在经济和环保效益都更好，“有了这么灵活的电气架构，我们几乎可以满足任何混动及纯电动动力系统。”

Evoque-e技术适用于轻度混合、插电式混合和纯电动配置。轻混HEV可搭载功率为66 kW（88.5 hp）的3缸柴油试验用发动机，标准9速自动变速箱，以及集成在两者之间的15 kW（20 hp）的辐射通量电机。该动力单元与48 V的电气系统和48 V的锂离子电池相连。

插电式混合动力车可搭载JLR的2.0 L 4缸Ingenium发动机，一个8速自动变速箱，以及一个集成在两者之间的辐射通量电机模块（连接320 V锂离子电池，最大输出功率可达150 kW）。

纯电动车则可搭载一个功率可达70 kW的锂离子电池和前后两个电机，为电驱动桥供电。前桥集成了一个单速变速器和一个85 kW（114 hp）的电机，电机使用铁磁和铝线圈；后桥则集成了一个较小的145 kW（194 hp）的电机。为提升性能，后桥电机采用了常规的钕磁和铜线圈，但需要搭配2速变速箱器。

为了致力于更多研究项目工作，Epple表示，在未来两年内该研发小组将扩充至500人，着重多学科长期研究：“电气化、智能化、车关网和人机界面都将有助于我们实现低碳的未来。”

JLR还将进行更多研究。Epple博士表示，两年内，公司先进研发小组的人数将翻一番，达到500人，并致力于解决多学科长期研究的挑战：“电气化、智能化、车联网和人机界面都有助于帮助我们打造低碳未来。”

当然，也少不了“亚麻”。

作者：Stuart Birch
来源：SAE《汽车工程杂志》
翻译：SAE上海办公室

JLR lightweight materials research blends flax, carbon fiber and cashew-nut oils

Jaguar Land Rover (JLR) is literally intent on harvesting energy saving solutions. “We are researching a range of new technologies to drive even more weight out of our vehicles, including how we could mix carbon fiber with flax,” reveals its R&D Director, Dr. Wolfgang Epple.

He says JLR is pursuing a bold electrification strategy and believes electric solutions are a must for premium carmakers to drive fleet average CO₂ emissions below 100 g/km (U.S. 56 mpg). But creating vehicles which are more fuel-efficient and sustainable "cannot be achieved by the introduction of hybrid and battery powertrains alone," he asserted, while noting that JLR's ‘Evoque-e’ research project with 12 technology partners includes a new and unique design of high performance, modular electric motor generators.

A high CARBIO diet 

The wider, complementary technologies are needed to achieve the holistic solutions required, Epple stressed, including parasitic losses in all areas: drag coefficient, friction, electrical, and heating, cooling and ventilation systems. And there is the need for more innovative approaches to weight reduction. That's where flax (a cultivated crop; textile fiber is obtained from its stem) and carbon fiber, enter the equation.

Simon Black, a JLR Senior Manager for Bodyshell and member of Epple’s team, explains: “The CARBIO project, in which we are a partner, combines layers of carbon fiber and flax with an environmental-friendly cashew nut oil resin. Flax was chosen for its inherent sound dampening properties. CARBIO combines the strength and lightweight benefit of carbon fiber with the sustainability and lower cost of flax. While the manufacturing cost of CARBIO is similar to that of traditional carbon fiber, the material cost of mixing carbon fiber and flax is one-third cheaper.”

Components made from CARBIO are 28% lighter than aluminum and 55% lighter than steel. Its NVH properties mean less use of sound-deadening material, Black noted.

But even the weight of the material that is required, could also be reduced via a research project calls LANDS (Lightweight and Sound) examining development of new NVH-abatement materials. One of these uses recycled plastic combined with filler sourced from the sugar refining process. A prototype wheel arch liner has been produced that is 9% lighter than a typical current type but provides similar noise reduction capability.

The CARBIO project has developed a carbon/flax hybrid automotive roof using Composites Evolution's Biotex Flax material. Together with vibration damping properties, flax fibers are renewable, lower in cost, and are CO₂ neutral. Bio-epoxy resins based on cashew nut shell liquid (CNSL) can offer enhanced toughness, damping and sustainability over synthetic epoxies.

A 50/50 carbon/flax hybrid biocomposite, made from Biotex Flax supplied byComposites Evolution and prepregged by SHD Composite Materials, has contributed to achieving the objectives of the project. With equal bending stiffness to carbon fiber, the hybrid biocomposite is described as exhibiting 15% lower cost, 7% lower weight and 58% higher vibration damping.

The prototype roof was designed by Delta Motorsport and manufactured by KS Composites. The CARBIO project is part-funded by Innovate U.K. (the British Government’s innovation agency). Other partners include Cranfield University.

Going PLACES 

Another significant project involving JLR is Varcity, evaluating how the company could introduce carbon fiber materials into its existing mixed material strategy for body structures with enhanced NVH properties, compared to current carbon fiber applications. The target is to achieve a 20% weight saving against an aluminum BIW.

“Varcity’s starting point was the Jaguar C-X75 concept,” says Black. “The bodyshell used an out-of-autoclave molding technique compatible with higher volume manufacturing.” Varcity is continuing R&D work on processing and forming technologies that could meet cost and volume requirements.

Vehicle wiring loom and electrical components are also getting the weight-loss R&D treatment, with the possibility of replacing them with wafer-thin printed electronic circuits. Typically a current Range Rover carries some 6000 m (19,685 ft) of wiring weighing 94 kg (207 lb). Use of thermoplastics for lighter seat construction are showing promise and the project PLACES (Premium Lightweight Architecture for Carbon Efficient Seating) has demonstrated seat structure 30% lighter than an equivalent in steel with no sacrifice of comfort, stated Black.

A thermoplastic composite stamping process is used. The structural components work as part of the comfort system for consolidation of parts.

New e-motor architectures explored 

JLR’s thermal management team is looking at the possibility of heating or cooling a cabin via what it terms an “air bubble” to maintain an equable temperature via several technologies including infra-red solar reflective glass, bespoke for specific temperature zones.

JLR also envisages infrared panels invisibly embedded parts of the cabin to warm occupants’ skin instead of maintaining the entire cabin at a specific temperature. Early tests show that it is possible to halve HVAC energy consumption from the current 8-12 kW.

All this is significant work, but it is powertrain that remains JLR's main single focus for energy saving. Mike Richardson, JLR’s Chief Technical Specialist, Low Carbon Vehicles, explains that the Evoque-e collaborative research project (12 partners and part-funded by Innovate U.K.) aims to look beyond 2020 to explore all aspects of advanced electrified powertrain technology. One of the key areas is to develop new, electric machine architectures.

“The radial flux machines that form the core technology for this are slim, light and extremely powerful,” states Richardson. “They produce up to twice the power and torque of current production technology. And they are scalable, capable of supporting any size of vehicle in our range and being modular, compatible with generic future components and systems.”

There is an added environmental plus for the new electric machines: “For applications where ultimate performance is not the priority, we are developing a version of the motor which trades iron-based ferrite magnets for typically used rare-earth neodymium, and copper windings instead of aluminum windings.” Savings are financial as well as environmental, he said: “An electric machine architecture this flexible will allow us to produce virtually any hybrid or battery electric vehicle configuration we choose.”

Evoque-e technology demonstrators embrace mild hybrid, plug-in hybrid, and battery-electric configurations. The mild HEV has a 66-kW (88.5-hp) 3-cylinder diesel research engine with a 15-kW (20-hp) radial flux electric machine integrated between the engine and a standard 9-speed auto transmission. This power unit is connected to a 48-V electrical system and 48-V lithium ion battery.

The plug-in has a prototype JLR Ingenium 2.0-L 4-cylinder engine and also has a radial flux electric machine (capable of up to 150 kW linked to a 320-V lithium ion battery) module between it and an 8-speed automatic.

The pure electric vehicle has a 70-kW lithium ion battery and electric machines front and rear powering electric drive axles. The front axle is integrated with a single speed transmission and 85-kW (114-hp) machine using a ferrite magnet and aluminum winding; the rear a smaller 145-kW (194-hp) machine. It uses traditional neodymium magnets and copper windings for added performance but driving through a 2-speed transmission.

There is more to come, and Dr. Epple reveals that JLR will double the size of its advanced research team to 500 within two years, focusing on long term multi-disciplinary challenges: “Electrification, smart and connected cars, and HMI (Human Machine Interface), all of which will help us deliver a low carbon future.”

And supported by "flaxable" solutions, of course.