THE INFLUENCE OF FILLET WELDS WIG REMELTING ON DURABILITY CURVES

Fatigue has been and will be a priority area of research, both internationally as well as nationally. In case of machine parts, cyclic loaded, below a certain level of stress, we can talk about fatigue strength, accounting an infinite number of stress cycles without intervening failure. In the case of welded structures that are composed from fillet welds, the situation is more complex because of the internal stress concentrators such as: cracks, pores and discontinuities of material and external: small cord radii to the base material, unevenness of the outer surface, high roughness, being able to talk in this case only about a limited lifetime, fatigue decreases with increasing values of stress cycle loaded. It must therefore find ways of increasing the fatigue lifetime of welded structures. The paper aims in this regard, is to study how increase the fatigue life time, by applying WIG remelting in the areas of intersection between the base material and welding seams, in the case of the fillet welded joints. It will be rise durability curves, we will make macro and micro structures, and micro-hardness measurements will be made in these area: seam weld, heat affected zone and base material.