| Popis: |
Residual stresses are one of the main conditioning factors of the mechanical behavior of components subjected to repair by welding. The magnitudes, directions, location and homogeneity of the residual stresses change with the chemical composition of the base material, the welding process, among other variables. Although it is inevitable to induce residual stresses during the welding process, it is possible to determinate magnitudes and directions using characterization techniques such as X-ray diffraction. In this work, the residual stress distribution measurement is carried out using a portable X-ray diffractometer in the welds of two types of steel (304 stainless steel and A36 carbon steel). On 304 stainless steel, the presence of residual compressive stresses on the base material and the thermally affected zone (HAZ) and residual stresses on tension on the weld seam were identified. For its part, for A36 carbon steel, a distribution of residual stresses in tension and random compression was evidenced in all areas of the sample due to the welding process and material formation. It is concluded that the heterogeneity in the type of residual stresses distributed over the material favors the weakening of the propagation of possible cracks that appear in the areas with residual compressive stresses and the strong influence of the chemical composition of the filler material of welding in the distribution and type of residual stresses that are induced in as a result of the joining process. |
