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The Abbott Firestone curve is an important method of surface characterization, especially when working with surfaces where it is necessary to introduce specific characteristics related to surface integrity and functional requirements for certain applications, an example of which is the interior walls of internal combustion engines, where specific tribological characteristics are sought, characterized by the distribution of peaks and valleys. These characteristics are not easily visible with the values of roughness parameters such as Ra or Rz, as the parameters are synthetic and do not provide information on the nature of the surface. The Abbott Firestone material percentage curve is, therefore, a suitable procedure for this purpose. When looking to characterize surfaces, measurements are taken at different points to obtain representative average values of the measurements, this implies for the case of surface characterization by Abbott Firestone curves, averaging different curves of each of the measured profiles to obtain an average curve. Due to the nature of the distribution of the peaks and valleys of the surface topography, each curve represents a particular distribution of peaks and valleys of the point where it has been measured, with its respective midline, this makes the process of averaging the values of each curve complex to obtain a single characteristic curve for measurements made on the surface. The curve comparison method proposed here serves this purpose, and it has also been found to be very useful, for example, for calculating the wear that a surface has suffered, as in the case of the interior walls of cylinders in internal combustion engines, hydraulic cylinders, or in controlled material starting processes, as in the case of plateau honing machining where the 3398 Milton Coba Salcedo et al. aim is to cut the peaks of the roughness profile at a certain height without modifying the valleys.

Burnishing is a machining process without chip removal that seeks to improve the surface roughness of a component by means of plastic deformation of the surface layers. Due to the process mechanics, during its execution, a compressive residual stress is introduced into the surface of the workpiece during its execution, which improves various physical-mechanical properties of the component. This process has been used industrially since the 1950s, mainly in pieces made of soft materials (hardnesses up to 45 HRC), in operations subsequent to processes such as turning. The development of tools with harder materials, has opened up the possibility of burnishing on harder materials (hardnesses up to 62 HRC). Burnishing of hard materials has opened up an alternative to traditional finishing processes such as grinding, its main comparative advantage is its low-cost operation, which reduces grinding costs by 8 to 15 times. The plastic deformation burnishing is a metal working process with material removal whose advantages are that it does not generate waste, which is a competitive advantage over other surface finishing processes such as grinding, where waste is generated which also needs to be collected 3940 Milton Coba Salcedo et al. and subsequently treated. The use of e.g. coolants is not necessary either, in recent years, attempts have been made to eliminate them from material working processes, because their presence not only causes a significant cost that impacts the manufacturing process, also represents an environmental problem due to its polluting effect, with the associated management costs involved. This article presents the results of an AISI 1045 test specimen experiment, to which a turning process has previously been carried out.

The chattering in the machine tools is a phenomenon that causes instability in the machining process, surface finish with high roughness, also produces excessive and accelerated wear on the tool in the metal cutting processes, this phenomenon consists of self-excited vibrations which are produced and maintained due to the cutting forces, the purpose of this article is to analyze regenerative chatter and predict the optimal points of operation in the turning process for 1020 carbon steel by developing analytical methods for generating stability lobe diagrams. To achieve this objective, the methods proposed by Altinas and Budak to stabilize the self-excited vibrations in the turning process applied to the orthogonal cut were studied in detail. These methods are widely accepted within the community of researchers and specialists in the field, thanks to the excellent results obtained in practice. Once the models studied were compressed, a computational algorithm was developed with the help of the MATLAB® software that was able to generate stability lobe diagrams for the turning operation in order to find the optimal points of operation so that there was no chatter, thus improving the material removal rate and increasing productivity.