Aluminum makes headway with Autos

Tata Motors, owner of Jaguar Land Rover, has announced that all future Jaguars and Land Rovers will be aluminum-built. It can be a difficult material to form and weld, but Jaguar has developed the skills and machinery to do so. Now it’s confident enough to build Land Rovers and Range Rovers from aluminum, too.

Taking out so much mass makes the vehicles accelerate and handle like smaller, sportier rides. Of course, the Range Rover Sport could be lighter still, but that would cut down on the sumptuous interior, the hidden third-row seat, the 1,700-watt, 23-speaker audio system and loads of smart technologies like lane-departure warning, adaptive cruise control, blind-spot monitoring, forward-collision sensing, cross-car traffic detection and parallel-parking assist. The eight-speed automatic transmission, independent suspension, massive four-wheel disc brakes and electric-assisted rack-and-pinion steering also increase efficiency and driving dynamics.

This is an expensive luxury vehicle into which the extra cost of a high-strength aluminum body structure can be absorbed. Using a combination of pressed panels, plus cast, extruded and rolled aluminum alloy parts, has resulted in a platform weight-loss reduction of 39 per cent compared to the previous model.

The body accounts for about one-third of the weight of a vehicle. A lighter body can ride on a lighter suspension. Engineers say that, for every 10 kilograms saved by reducing the weight of the body, another 10 kilograms can be saved by downsizing other parts of the car. Jaguar Land Rover has moved into aluminum construction in a bigger way than any other mass-market manufacturer and has overcome some serious issues in the process.

That has enabled the aluminum Jags, Land Rovers and Range Rovers to all be unibody, short for unitized body, which is the design used for steel automobiles. In a unibody, the vehicle’s body panels are joined together to form a strong shell structure and this is not an easy trick in aluminum. The other approach is to employ a space-frame design, which is essentially an aluminum alloy frame structure covered with a thin aluminum skin. That only works well for expensive, low-volume cars like the mighty Audi R8.