R Velusamy, Chief of Global Product Development, Mahindra & Mahindra, has cleared a misconception that safe cars have to be heavy. “Once you decide to achieve 5-star safety, there is no option but to reduce vehicle weight. You need a lot of focus on BIW (body-in-white) mass (which is going to crash at 65kph). You can use hot formed steels at different part of the vehicle."
He was speaking during a one-on-one conversation with Autocar India editor Hormazd Sorabjee on the first day of Autocar Professional’s 2021 Vehicle Lightweighting Conference today.
Velusamy pointed out that around 110kg of Mahindra’s new XUV700 flagship SUV was reduced with innovative design and use of high tensile steel and plastic composites. The tailgate was one of the areas where the company could reduce around 15-20 kg.
Use of new materials
When it comes to reducing weight in automobiles and thereby enhancing efficiencies, aluminium is being considered as one of the key new materials. But aluminium also increases cost.
According to Velusamy, doors, fenders, bonnet, suspensions can be considered for the use of alternate materials. He mentioned that use of high tensile steel, advanced high tensile steel, ultra-high tensile steel and boron steel can be used at different aspects of the vehicle. These four steels can be used in different parts of the vehicle.
“In powertrain too, you can do a lot of weight reduction. Aluminium blocks improve manufacturing and 30-35kg can be reduced. There are some key areas for lightweighting including powertrain and BIW (Body In White) using advanced high-strength steels instead of mild steels,” he mentioned.
He also stressed that with EV penetration there will be an increase in weight and there is a necessity to find new materials, “in EV reinforcement this will play a major role.”
“Criterion for selecting areas where weight can be reduced in a vehicle include dynamics of the vehicle, optimisation of suspension, and reducing the BIW mass. More than technology it has become the cost aspect. We try to work with aluminium forgings, but the design has to allow it to work with. The cross-bar beam and steering wheel are candidates for use of magnesium. Plastics can do wonders for areas like the fender and tailgate,” he pointed out.
Velusamy signed off stressing on the need to keep consumer requirements in mind and giving priority to addressing their interest, “customers need quality products and design will undergo change due to their need for improved NVH levels, ride and handling, top-notch safety and tech features. OEMs need to be innovative to reduce vehicle weight.”