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Jaguar XE treads lightly thanks to new alloy

The new Jaguar XE is the first car in the world to be built from a new grade of high strength aluminum called RC 5754, which was developed specifically for the XE. This new alloy features a high level of recycled material and makes a significant contribution to Jaguar’s goal of using 75% recycled material by 2020. 

Jaguar is a world leader in the use of aluminum in car design, having built up years of experience with models like the F-Type. The monocoque is constructed from 75% aluminum. Due to the weight saving the XE is said to deliver over 75 mpg (less than 4 litres/100km) on EU combined cycle in its most efficient guise. It should also emit less than 100g/km carbon dioxide. 

Automotive Industries (AI) asked Nick Miller, Vehicle Programme Director, Jaguar Land Rover, what are the benefits are of the new Advanced Aluminum Architecture?

Miller: When we began the development of the new platform we decided from the start it would be aluminum, so we looked at what the requirements were going forward for that type of vehicle, and obviously one of the key drivers is efficiency. And a big part of efficiency in a fuel perspective is weight. That meant we decided quite quickly that using our aluminum monocoque construction was going to be the right decision for this car.

As we got into it more and more we than ended up with a mixed metal (so it’s not 100% aluminum). It is a mixture to provide better weight distribution. When we were investigating the weight distribution of the bolt-on components – including our choice of suspension architectures – we realized that we wanted to apply some steel at the rear to get the balance right. The XE is conceptualized as a four cylinder car. With the steel we have at the rear of the car we deliver that 50/50 ratio balance exactly. Because the body shape is such a huge investment we recognized we may want to reduce the weight further in the future. We can achieve this through saving weight on our bolt-on parts in the future, without having to change the body shop.

AI: The Jaguar XE body uses a class leading 75% aluminum content. What advantages does that bring apart from the low weight?

Miller: Stiffness is a key enabler to delivering the right handling characteristics as part of the Jaguar DNA. Let me give you an example of the front suspension. There are a number of elements in the front suspension design. First are the design requirements of the car. Our team wanted a low front fender position. The double wishbone layout gives the opportunity to lower the front. We also wanted to give the stiffness and steering feel of an XE car so we set out to design knuckle and front suspension components with the stiffness of an XE car. But, there is no point in having really stiff parts if the body shell it is mounted to is soft. So we also focused on attachment point stiffness. The targeted attachment point stiffness for XE is the same as the F-Type. All the things we learned from the last two very sporty cars have been used for the XE. I think we have achieved a balance of weight and stiffness.

AI: How does the new modular architecture help to meet the design demands in shaping aluminum?

Miller: Jaguar’s new Advanced Aluminum Architecture has opened up a world of opportunities in shaping aluminum. The new XE form is the product of 12,000 computational fluid dynamics simulations and more than four million hours of processor time.
We’ve been using aluminum for a long time in JLR, and our capabilities have improved significantly. A good example would be the look of the car. There is a line from the head-lamp at the front fender, through the doors into the rear and round the bonnet. It is a single line all the way through. If you look at the rear part of that the whole of the body side is a single aluminum pressing. We spent a lot of time on developing that particular line that runs through. It is a very dramatic line and it is quite challenging to get to flow right. The other area was the bottom of the B-pillar of the rear door where the foot swings when you get in and out. We spent a lot time reducing it to the tightest possible radius to give us a very competitive foot swing without splitting the material during the stamping of the panel.

AI: What other unique materials are you using in the XE apart from aluminum?

Miller: RC5754 is a state-of-the-art alloy that helps to deliver extremely high levels of torsional stiffness which gives XE exceptional vehicle dynamics, agile handling and class-leading steering response. A stiff shell is also fundamental to achieving the highest levels of crash safety and occupant protection: XE has been engineered to exceed global safety standards. This is a material we developed to increase the use of recycling material. It has very similar characteristics as the existing alloy, taking the content up to 75% recycled material came out of a research project we did with Novelis and Warwick University.

AI: What In-car technologies can we find in the new XE?

Miller: The Jaguar InControl Remote allows users of iOS and Android smartphones to connect to the car from wherever they are and control a range of vehicle functions, including climate control, locking or unlocking the doors, or even starting the engine. Jaguar InControl Apps allow users to seamlessly access smartphone apps through the vehicle’s touch-screen, making it easy to do everything from make a conference call, find a parking space or book a hotel room.
The new XE’s InControl infotainment system is designed around an 8-inch Touch-screen. It’s clear, intuitive, quick and easy to
access and uses voice control plain speech. The XE also functions as a Wi-Fi hotspot, enabling multiple devices to connect online where coverage is available.

Other technologies include a laser Head-Up Display. The laser gives you a stronger light source when you are in direct sunlight than the conventional LCD, without as much washout of the image on the screen. The technology provides the driver with information such as speed and navigation instructions with maximum clarity and minimum distraction.

AI: What are your targets with the new generation Ingenium engine family?

Miller: We knew we wanted to focus on four cylinder engines. The power plant has a modular design in terms of each cylinder, and there is commonality between diesel and petrol so it is a family of engines. We are starting with a four cylinder diesel, but will relatively soon introduce a four cylinder petrol version. What we are trying to do is to give refined engine performance in terms of power, efficiency and friction reduction within the engine. Friction reduction was a key element of the design.

AI: What efforts do you make with the new XE to reduce Jaguar’s carbon footprint?

Miller: We make panels across three press shops and at two big suppliers. All of those press shop areas have materials segregation so we separate the scrap from the different alloys we stamp panels out of. This helps Novelis in the recycling of the scrap as they know the alloy contents of the scrap exactly. In terms of other elements of the carbon footprint, I guess one would be the huge solar panel system we put on the top of the new engine plant in Wolverhampton, and which meets 30% of the power requirements of the factory

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