A recent addition to the company's TechnoElast range, the material provides just the required combination of stiffness and elasticity for this application and has very good injection moulding properties thanks to its high melt flow. Another aspect in material selection was its high weather and UV resistance, given that the front spoiler lip is exposed to spray water, road salt solutions, dust, and wide temperature variations throughout its service life. The part was developed by SLM Kunststofftechnik GmbH of Oebisfelde/Germany.
Measuring about 1.70 m in length, the spoiler lip is situated underneath the car's
front bumper. On the one hand, its function there is to protect the front spoiler and bumper assembly from damage of the kind that typically occurs during parking near high kerbs. Furthermore, the spoiler lip helps to reduce the vehicle's drag coefficient and cuts the level of wind noise during travel. Thanks to its balanced stiffness-to-elasticity ratio, the TechnoElast V D4011 I 1 material employed (Shore hardness 40) prevents the front spoiler lip from deflecting backwards under the wind pressure, which would promote the formation of air vortices under the car.
In addition, the TPO compound is weather and UV resistant and retains its mechanical properties even at temperatures as low as -40 °C. It is also easy to process thanks to its very good melt flow, which ensures uniform filling of the mould despite the component's substantial length and partially low wall thickness of only 1.5 mm. Furthermore, the material yields a very high-quality surface finish.
The TPO compounds of TechnoCompound are based on a polyblend of polypropylene and EPDM rubber. Products from the TechnoElast range are available in Shore hardness grades A through D and provide good processing properties, high temperature resistance, good damping characteristics and a high elastic resilience.