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The paper presents the results of strain measurement using two methods: videoextensometry (ME46) and digital image correlation (DIC)-ARAMIS. ME46 - allows measuring and monitoring the major and minor strain on a planar surface of a loaded object [1]. Experimental equipment uses a CCD camera for monitoring the process. The software calculates the displacements of contrast dots and subsequently the strain components are obtained. Another method for non-contact measurements is DIC technique; the measurements are done using three-dimensional image correlation system. The system uses two digital high-speed cameras providing a synchronized stereo view of the specimen where speckles are arranged on the surface. The results show the complete strain field during the tests, including details of the strain field when necking develops prior to the failure [2]. Experimental results obtained on ultra high strength automotive steels DP 1000 and 1400M grades during static tensile test are presented in the paper. The outputs of both are deformation maps. Advantages and disadvantages of both methods are compared.

Videoextensometry is a new experimental technique for non contact strain measurement, which enables measuring of longitudinal and transversal strain components on a planar surface of a loaded object. Experimental equipment uses a CCD camera (640 × 480 pixels) for monitoring the process on a surface area of 20 × 10 mm 2 . The special software calculates the displacement of contrast dots prepared on the specimen surface. The paper presents results obtained experimentally on two steel grades for automotive steel sheet during tensile testing at different strain rates in the quasi static loading range. Non contact strain measuring is used for monitoring the strain development and strain localization. K e y w o r d s : microalloyed steel, interstitial free steel, deformation

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