Improvement on Tensile Test Accuracy Utilizing Non Contact Video Gauge

By utilizing non contact video gauge of IMETRUM corporation at MTS 810 material testing system equipped with contact extensometer, results comparison about static tensile testing of painting specimens made of Q235 steel was performed. The results show that stress versus strain curves obtained by these two different instruments nearly coincide. In elastic deformation and yield stage the two curves also coincide better. Acquired mechanical properties by means of these two different instruments coincide basically. In elastic deformation stage relationship of stress versus strain by means of video gauge curves slightly, and its linearity is relatively lower, but acquired Young’s modulus of elasticity by means of video gauge is almost equal to that by contact extensometer. In summary, painting treatment on the specimen surface can improve significantly accuracy about static tensile testing of metallic material by utilizing IMETRUM video gauge.