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The development of biomedical devices has improved the quality of life for millions of people. The increase in life expectancy generates an increase in the demand for these devices. One of the most used materials for these purposes is 316 L austenitic stainless steel due to its mechanical properties and good biocompatibility. The objective of the present investigation was to identify the dependence between the main cutting force, the initial speed of the tool wear, the surface roughness, and the parameters of the cutting regime. Based on these dependencies, a multi-objective optimization model is proposed to minimize the energy consumed and initial wear rate, as well as to maximize productivity, maintaining the surface roughness values below those established by the ISO 5832-1 standard. The wear of the cutting tool was measured on a scanning electron microscope. For the optimization process, a genetic algorithm based on NSGA-II (Non-nominated Sorting Genetic Algorithm) was implemented. The input variables were the cutting speed and the feed in three levels. The cutting force and surface roughness were set as restrictions. It is concluded that the mathematical model allows for the optimization of the cutting regime during dry turning and with the use of MQL (Minimum Quantity Lubrication) with BIDEMICS JX1 ceramic tools (NTK Cutting Tools, Wixom, MI, USA), of AISI 316 L steel for biomedical purposes. Pareto sets and boundaries allow for choosing the most appropriate solution according to the specific conditions of the workshop where it is applied, minimizing the initial progression of tool wear and energy consumed, and maximizing productivity by guaranteeing the surface roughness values established for these types of parts according to the standard.

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En este trabajo se estudia la modelación de estructuras híbridas de andamios porosos para regeneración de tejido óseo basadas en las superficies minimales triplemente periódicas Giroide (G) y primitiva de Schwarz (P). El diseño de las probetas prismáticas híbridas, con dimensiones según la norma ASTM D695_15, se logra a partir de las ecuaciones que definen a cada estructura utilizando la función de enlace sigmoidea con valor k=0.5 mediante el software CAS Wolfram Mathematica v11.2. Los aspectos relacionados con el uso de Mathematica como herramienta para el diseño de las probetas son discutidos en detalle. Las constantes de la ecuación de cada estructura son utilizadas como variables en un diseño factorial 32 para estudiar su efecto en la porosidad y tamaño de poros. A partir de regresión multilineal se obtienen las ecuaciones que relacionan los factores con las variables dependientes y se discuten los modelos obtenidos. Se concluye que el modelo bilineal es adecuado para la descripción de las variables de respuesta lo que justifica la elección del diseño experimental utilizado.