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This work reports on the results of a study of different macro-geometrical deviation parameters, such as Straightness (SD), Parallelism (PD) and Circularity (CD) as a function of cutting speed (v) and feed (f) of dry turned UNS A92024 (Al-Cu) cylindrical bars. The results obtained have allowed establishing exponentials parametric model for predicting these deviations as a function of those cutting parameters. As a consequence of that, geometrical surfaces SD(f,v), PD(f,v) and CD(f,v) have been developed for this alloy. These surfaces allows determining marginal curves for specific v and f values, respectively, out the parameter ranges employed. So, macro-geometrical deviations can be predicted through this model for v and f values out of those considered in the study for each alloys.

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Manufacturing performance improvement must take into account energetic, environmental and economic considerations. Thus, when intermediate manufacturing processes are avoided, that performance is improved from the cited viewpoints. In the aeronautical industry, pre-shaped elements of UNS A92024 alloy based structural elements are machined in T3 temper state previously to be thermally treated to reach an O state in order to facilitate its posterior plastic forming process. In this work, a comparative study on the dry turning of UNS A92024 alloy in both states has been achieved in order to analyze the possibilities of eliminating the thermal treatment process, so improving the three above commented considerations. This study has been carried out on the basis of the analysis of surface finish and cutting tool wear.

Wear of elements subjected to friction and sliding is among the main causes of low tribological performance and short lifetime of strategic materials such as titanium alloys. These types of alloys are widely used in different areas such as aerospace and the biomechanics industry. In this sense, surface modification treatments allow for the overcoming of limitations and improvement of features and properties. In the case of titanium alloys, improvements in the main weaknesses of these materials can be obtained. Laser texturing of UNS R56400 (Ti6Al4V) alloy, according to Unified Numbering System designation, surface layers in a non-protective atmosphere produces an increase of the oxides, especially of titanium dioxide (TiO2) species. The presence of oxides in the alloy results in color tonality variations as well as hardness increases. In addition, specific roughness topographies may be produced by the track of laser beam irradiation. In this research, thermochemical oxidation of UNS R56400 alloy has been developed through laser texturing, using scan speed of the beam (Vs) as the process control variable, and its influence on the sliding wear behavior was analyzed. For this purpose, using pin on disc tribological tests, wear was evaluated from the friction coefficient, and wear mechanisms involved in the process were analyzed. Combined studies of wear mechanisms and the friction coefficient verified that by means of specific surface treatments, an increase in the wear resistance of this type of alloys is generated. The most advantageous results for the improvement of tribological behavior have been detected in textured surfaces using a Vs of 150 mm/s, resulting in a decrease in the friction coefficient values by approximately 20%.