EFFECT OF VIBRATION ON THE VARIATION OF RESIDUAL STRESSES AND IMPACT ENERGY IN BUTT-WELDED JOINTS
The effect of vibration on the variation of residual stresses in butt-welded steel plates and on the impact energy in characteristic zones of a welded joint is analysed in this paper. An important segment occurring as a result of welding is the phenomenon of residual stresses in the welded joint zone. Residual stress measurements are conducted both on butt-welded plates that were not vibrated during welding and on plates simultaneously welded and vibrated. It is concluded that the vibration process noticeably decreases the level of stresses in the zone of the butt weld, i.e. the result is relaxation and plane stress state. Impact energy tests have shown that vibration favourably affects the total impact energy by increasing it both in specimens notched in the weld metal (WM) and in the heat-affected zone (HAZ). It is also concluded that the correlation between the distribution of crack initiationand crack propagation energy, as vital components in the assessment of welded joint ductility, is improved. Ključne reči • zavarivanje • zaostali naponi • vibracije • energija udara