2013 Accord featuring first use of new Honda emissions aftertreatment catalyst and new technology to weld together steel and aluminum
|The new catalyst enhances the performance of palladium, also allowing a reduction in rhodium use. Click to enlarge.|
The 2013 Honda Accord, due to go on sale in the US on 19 September, features the first use of a new Honda-developed catalyst which significantly reduces the precious metals required in catalysts for emissions aftertreatment. Honda will continue to adopt this catalyst sequentially to other models.
The 2013 Accord also features first use of a new technology for the continuous welding of the dissimilar metals of steel and aluminum. Honda applied this for the first time to the vehicle subframe, a key component of a vehicle body frame. Honda will expand application sequentially to other models after the Accord.
Catalyst. With the backdrop of the increasing volume of global automobile production and the global trend of strengthening emission regulations, the demand for precious metals used for catalyst, including platinum, rhodium and palladium, is expected to continue to increase in the future. Honda has been committed to the effort to reduce the use of precious metals for its catalysts, and has successfully applied a catalyst that does not contain any platinum into practical use with the current model of the North American Accord.
The newly developed catalyst allows palladium to speed up the process of absorption and desorption of oxygen, therefore enabling reduced use of rhodium in the purification of exhaust emissions. The adoption of this new catalyst will reduce overall use of precious metals by 22% (including a 50% reduction in rhodium) compared to the current model of Accord.
Moreover, the development of the new catalyst has reduced the cost by 37% while complying with the California state standards in SULEV category of the LEV II regulation.
|Conceptual diagram of FSW of dissimilar metals. Click to enlarge.|
Welding steel and aluminum. Striving to reduce vehicle weight in order to increase fuel economy, Honda focused on Friction Stir Welding (FSW) and developed a new technology for the continuous welding of steel and aluminum. This technology generates a new and stable metallic bonding between steel and aluminum by moving a rotating tool on the top of the aluminum which is lapped over the steel with high pressure. As a result, the welding strength becomes equal to or above conventional Metal Inert Gas (MIG) welding—a welding technique most commonly used for welding of identical materials such as steel-to-steel or aluminum-to-aluminum.
This new technology contributes to an improvement in fuel economy by reducing body weight by 25% compared to a conventional steel subframe. In addition, electricity consumption during the welding process is reduced by approximately 50%.
|Front subframe. Click to enlarge.|
It also enabled a change in the structure of the subframe and the mounting point of suspension, which increased the rigidity of the mounting point by 20% and also contributed to the vehicle's dynamic performance.
Furthermore, Honda established a new method to apply this technology to mass-production vehicles. Conventionally, FSW required use of large equipment, but Honda developed a FSW continuous welding system applied to a highly versatile industrial robot. This system also can be used for aluminum-to-aluminum welding and thus, the welding system with the same specifications can be used for production of a full-aluminum subframe.
Honda also developed a non-destructive inspection system using a highly-sensitive infrared camera and laser beam, which enables an in-line inspection of the bonding location for every unit.