Composites Testing

Basic identification of plastic can be accomplished by using three analytical tests. FTIR (ASTM E1252), EDS, and TGA (ASTM E1131) analyses. A typical summary statement for a basic material identification report might read “The FTIR, EDS, and TGA analysis of the sample was consistent with that of a polycarbonate with 10% glass filler.” This combination of tests provides basic information but additional testing is needed if identification of a trace additive or the grade of plastic is required. However, if your composite is reinforced with an organic filler (such as Carbon Fiber), TGA or ash content will not be able to quantify the amount of reinforcement. A material specific digestion may be needed, for example ASTM D3171-method B: digestion in sulfuric acid and hydrogen peroxide.

There are a wide variety of tests used for mechanical testing of plastics but some of the more common are Tensile Properties (ASTM D638 or ASTM D3039), Flexural Properties (ASTM D790), and Izod Impact Strength (ASTM D256). Mechanical testing is most often performed on molded test bars but we also have a complete machine shop so we can fabricate test bars out of stock material or even parts.

Composites used in electrical applications often requires testing such as Dielectric Strength (ASTM D149), Dielectric Constant (ASTM D150), Volume Resistivity (ASTM D257), or Surface Resistivity (ASTM D257). These tests are typically performed on flat plaques.