EVALUATION OF LOCAL MECHANICAL PROPERTIES OF STEEL WELD BY MINIATURE TESTING TECHNIQUE

摘要

The paper deals with the determination of local mechanical properties of steel weld by miniature testing techniques. The aim of this work is to show the application of miniature samples for determination of local properties and, further, the prediction of components residual service life. Small Punch test (SPT), Micro-Tensile test (M-TT) and instrumented mini-Charpy impact test are employed here. The SPT method uses a small disk-shaped testing sample of usual dimension of 8 mm in diameter and 0.5 mm in thickness. On the basis of SPT specimen, an M-TT specimen shape was suggested with thickness of 0.5 mm, width of 1.5 mm and parallel length of 3 mm. ARAMIS system using Digital Image Correlation method (DIC) enables measurement of the strain during M-TT with high accuracy. The correlation between small punch test results, microtensile test results, mini-Charpy test results and results of conventional tests which were used as a reference method are investigated in this paper.