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The concept of machinability can be related to the facility of cutting of a specific material using a set of prefixed criteria depending on the manufacturing process. Because of this, the study of the machinability of a material requires the knowledge of a high number of parameters.Traditionally, the materials to be machined have been steels and cast ferrous alloys. A large number of studies on their machinability can be found in the literature in contrast to aluminium and its alloys, although in recent decades their industrial applications have increased considerably, especially in relation to the machining processes. The aim of this work is to assemble the few available data in the literature about the machinability of aluminium and aluminium alloys. These data have been structured and presented in order to systematize the machinability parameter study of aluminium alloys. in arbitrary units, values of magnitudes related to several properties versus the purity percentage of the metal. It can be observed that, while deficient properties are improved, the value of other properties decreases due to the addition of impurities. When selecting an aluminium alloy for an industrial application, an optimum balance among its properties must be sought. In this way, aluminium alloys are considered an effective solution for resolving manufacturing problems of mechanically resistant and hard-wearing elements because of its low weight-mechanical strength ratio, e.g., brake drums in the automotive industry, where gray cast is replaced by high mechanical strength and hard-wearing Al-Si alloys. Other instances can be found in the aerospace industry. One of the causes of the development reached by this industry can be related to the obtaining of work hardening aluminium alloys resistant to moderately high temperatures. On the other hand, aluminium alloys show good workability in casting /3/, forming /4/ and machining 151, as well as excellent behaviour against corrosion 161, high reflectivity, low emission power and unbeatable electrical and thermal conductivities 111. Owing to all this, aluminium and aluminium alloys are present in a wide range of industrial applications. In addition to the aforementioned industries, food, naval, electrical and others can be cited.00

Carbon Fiber (CF)/Metallic Alloy (MA) laminar structures, also known as Fiber Metal Laminates (FML) allow diminishing the airship weight. Because of that the use of these materials is growing continuously in the aerospace industry. These composites materials need to be drilled because of the assembly requirements in the different airship elements. The most common problems that can appeared when those structures are machined are related with the interaction of the tool with dissimilar materials, which need different cutting parameters for the optimized machining process. This work reports on the results about a study of the dry drilling processes of hybrid composites Carbon Fiber/aluminum alloy, and especially CF/AA2024.

In this work, a study on the dry turning process of UNS A92024 alloy has been carried out. This study has been achieved on the basis of the analysis of the surface finishing of the machined pieces in terms of roughness parameter, R a , as a function of cutting speed, v, and feed, f. The aim of this work has been devoted to establish R a =R a (v,f) parametric relations. Two steps have been followed in order to obtain these relations.Thus, in a first step, R a (v) and R a (f) potential curves have been fitted to experimental data using a linear fitting in the log-log plane. After this, in a second step, those curves have been treated as Bizier curves to construct a Coons surface R a (v,f). A mathematical expression of this surface has been obtained by fitting(v,f,R a ) experimental data to a combined R a (v,f) potential model. The obtained parametric relation can thus be used to predict the surface quality of the turned pieces when different values of cutting speed and feed are applied.

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