Mini Flat Tensile Specimens and Various Methods for Testing them. For the determination of mechanical properties, when only small amounts of material are available, e.g. welded joints, sheets, failure analysis, gradients of mechanical properties,specimens with very small dimensions can be used. A common specimen type is the mini flat tensile specimen with measuring length being 9 mm, width 2 mm and thickness 0.5 mm. Common testing devices which are designed for larger specimens are not applicable to mini flat tensile specimens. Therefore, tip to now usually the stroke of the crosshead of the testing machine is measured as substitute for the real elongation of the specimens gauge length, thus leading to inaccuracies. By the means of a new developed testing device a gauge is applied directly on the specimen. This allows to measure the real gauge length of the specimen. Elongations up to 80% can be measured on this way. The principles of the various testing devices are explained and the resultsobtained from them are compared with those of standard round tensile specimens tested according to standards. Emphasis is put on the determination of the yield strength and the slope in the linear-elastic regime. The latter is frequently used assubstitute for the Young's Modulus. Recommendations for the application of mini flat tensile specimens are given. The advantageous application on welded joints is demonstrated.
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