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Many researchers demonstrated the capability of Abrasive Waterjet (AWJ) technology for precision milling operations. However, the concurrence of several input parameters along with the stochastic nature of this technology leads to a complex process control, which requires a work focused in process modelling. This research work introduces a model to predict the kerf shape in AWJ slot milling in Aluminium 7075-T651 in terms of four important process parameters: the pressure, the abrasive flow rate, the stand-off distance and the traverse feed rate. A hybrid evolutionary approach was employed for kerf shape modelling. This technique allowed characterizing the profile through two parameters: the maximum cutting depth and the full width at half maximum. On the other hand, based on ANOVA and regression techniques, these two parameters were also modelled as a function of process parameters. Combination of both models resulted in an adequate strategy to predict the kerf shape for different machining conditions.

In laser surface treatment the laser beam is used as energy source for surface modification improving aspects such as mechanical properties, tribology or surface texture. Modeling tools have special interest in processes with many variables, like laser surface processing, in order to minimize the tryout testing to find the optimal process parameters. The work presented here focuses on the prediction of the final topography in laser polishing process. By FFT analysis of the surface profile it is possible to get the different frequency components of the initial topography. On the other hand, thermal field simulation was carried out to evaluate the melt duration. Matching this with the spatial frequency damping during process, the reconstruction of the processed topography was obtained.

In the last years the laser cladding has become an important technology that has been studied by several industries as automotive or aeronautical. Therefore, although this technology was used initially for coatings, actually it is being used for repairing or even direct manufacturing of high added value parts. In this paper, the application of laser cladding for repairing a GGG70L stamping die is presented. The first step is to present the methodology used to obtain the optimum conditions for AISI 316L stainless steel clads on structural steel (DIN C45). The next section shows a deeper study about the capacity of the process to fill standard geometries on DIN C45 and DIN 1.2379. Finally, a nodular cast iron GGG70L stamping die is repaired using laser cladding process. The parameters and strategy used for the repairing have been obtained on previous sections. Furthermore, in the final section a powder concentration model is presented as the first step to create a complete model that simulate the three stages of laser cladding: interaction between powder and laser beam, creation of melt pool and generation of clad geometry.

Polishing operation of die and molds represents up to 30% of the total manufacturing cost, since it is a high added value operation that is necessary carried out manually by qualified personnel. There are several alternatives to hand operations, such as abrasive automated methods operated by robots, ball burnishing or laser polishing process in order to reduce operation time and costs. The presented article proposes a laser based polishing operation which consists in the application of a laser beam in a very controlled way. The radiated energy melts a microscopic layer which flows and re‐solidifies smoothing the topographic irregularities of the surface resulting in a reduction of the initial roughness. The article presents, in addition to some experimental results of laser polishing process, a thermal model developed based on the finite difference method. The model is able to take into account different types of lasers; in particular, simulations for a CO2 laser and a high power diode laser have been carried out. As the model gets the full map of temperatures in 3D, it is possible to predict the melted material layer thickness, which is a crucial parameter in the laser polishing process. Finally, two types of validation tests are presented: First, some tests measured by pyrometers on the test part surface. Secondly, the comparison of a series of metallographic analysis on W.‐Nr.1.2379 tool steel, where the metallurgical changes caused by the laser radiation can be observed with the thermal field estimated by the model.