Mechanical Characterization of GFRP Laminates; Digital Image Correlation Technique vs. Conventional Extensometer Measurement

Accurate and reliable characterisation of constitutive properties plays a vital role with respect to design and analysis of the materials with highly anisotropic mechanical properties e.g. fiber reinforced composite materials. This paper experimentally characterises thein-plane mechanical properties of glass/epoxy composite material using digital image correlation (DIC) techniqueand conventional extensometer measurement method. Test samples are extracted from laminates fabricated using vacuum infusion process (VIP) and tested according to ASTM D3039 and D3518 standards. Comparison of stress-strain curves derived from DICand extensometer data, under monotonic loading, shows that the DIC technique measures more strain than theextensometer. The source of this difference is attributed to the slip of extensometer when the specimens are stretched while using the DIC technique, no error is introduced due to slip since it is a non-contact measuring technique. Flexibility and simplicity of experimental set-up make the DIC technique a very practical method for characterization of composite materials.

کلیدواژه ها:

Digital image correlation (DIC) ، Material characterization ، Ncorr ، Composite material