DETERMINATION OF FRACTURE TOUGHNESS AND TENSILE PROPERTIES OF STRUCTURAL STEELS BY SMALL PUNCH TEST AND MICRO-TENSILE TEST

The paper deals with the determination of mechanical properties using mini-samples. Miniature samples testing techniques can be considered as non-destructive ones and very convenient for local mechanical properties assessment. The mechanical properties of the individual regions of welds or actual material properties of components in service and in all other cases with lack of material can be evaluated for example. One of the methods of the highest interest is small punch test (SPT). Another miniature sample based method is using micro tensile samples. There is currently investigated possibility of micro samples made of the same material volume as in the case of SPT. The micro tensile samples are loaded in the same mode as in the case of standard tensile tests and thus the evaluation can be done without knowledge of any empirical correlation as in the case of SPT. The correlation between small punch test results, micro-tensile test results and results of conventional tests which were used as a reference method are investigated in this paper.