In passenger cars as well as in commercial vehicles, the trend towards light-weight design is still the decisive issue for the automotive industry. And with good reason: every gram that is saved brings crucial advantages such as lower consumption, and this in turn means lower emissions as well as a fall in operating costs and a rise in the useful load. And last but not least, stricter CO2 emissions guidelines and exhaust gas standards are the driving force behind innovations. As a development partner to the industry, ContiTech constantly works on new solutions to make their components in the vehicles even lighter. The greatest challenge here is to meet the customers’ requirements for the application in question while also complying with the mechanical requirements for stiffness, strength, service life, and vibration behavior.
“Simulation technology has become indispensable in satisfying our customers’ requirements and meeting our own quality standards,” explained Dieter Kardas, responsible for pre-development at ContiTech Vibration Control.
Since 2006, ContiTech has used fiberglass-reinforced polyamide as a light-weight alternative to steel and aluminum for components in passenger cars. The weight-reduced components achieve weight savings of up to 50%. Whether it is the support mounting for the chassis, engine mount, or transmission crossbeam, ContiTech is working on innovations and develops new light-weight components using the weight-reduced materials.
A challenge in making calculations for injection-molded parts comes in the form of the anisotropic material properties that arise due to the fiberglass-reinforced polyamide. The direction of the glass fibers has a decisive influence on local mechanical component properties. Simulation processes are used to make visible the effects of microscopically small glass fibers on the mechanical properties of the assembly. In the development process, design studies are first of all conducted with simplified isotropic material descriptions. The design is then assessed using anisotropic material properties.
The direction of the glass fibers depends on the production process, among other things. For this reason, the mold filling process must first of all be calculated. One result of this calculation is the orientation of the glass fibers. This information is then used to calculate the anisotropic material properties that are unevenly distributed in the component. On this basis, the different mechanical component properties can be assessed by means of finite element calculations.
“Our goal is to support and improve the product development of light-weight components by using the opportunities offered by simulation methods,” concluded Kardas. “We can use the simulation methods to predict the mechanical component performance at a very early stage and thus guarantee high quality for the components.”