Ductile-Brittle Impact Behavior of High Impact ABS

The impact behavior of plastic materials can be investigated using a number of test procedures. Falling dart and notched Izod are the two most commonly used tests. Each has certain limitations. The Notch Bend test utilizes a load cell feeding an oscilloscope to generate a load-deflection curve. From this curve and visual examination of the broken test specimens, it is possible to define the conditions that cause a transition from ductile to brittle impact behavior. Environmental tests performed on a passenger car illustrate the reheat times of an instrument panel from −20°F. The combination of impact testing and reheat data support the use of high impact ABS for critical interior automotive applications.