Despite the significant effect of the improvement treatments on the fatigue strength of welded elements, their importance is not reflected sufficiently in corresponding codes and regulations. The main problem in that area is that the effect of improvement treatments, particularly UP, on the fatigue life of structural elements depends greatly not only on the level of induced residual stresses, but also on mechanical properties of used material, the type of welded elements, parameters of cyclic loading and other factors. Presently, elaborate, time- and labor-consuming fatigue tests of large-scale specimens are required for this type of analysis.
For the effective application of UP, depending on the above-mentioned factors, a software package for Optimum Application of Ultrasonic Peening (a maximum possible increase in fatigue life of welded elements with minimum labor- and power-consumption) was developed based on original predictive model. The main functions of the developed software are:
- Determination of the maximum possible increase in fatigue life of welded elements by UP, depending on the mechanical properties of used material, the type of welded element, parameters of cyclic loading and other factors.
- Determination of the optimum technological parameters of UP (maximum possible effect with minimum labor- and power-consumption) for every considered welded element.
- Quality monitoring of UP process.
- Final fatigue assessment of welded elements or structures after UP, based on detailed inspection of UP treated zones and computation.
The supporting software allows one to assess, through calculations, the influence of UP on the service life of welded components without having to perform the time and labor-consuming fatigue tests and to compare the results of calculations with the effectiveness of other improvement treatments such as heat-treatment, vibration treatment, overloading etc.