Implementación de un sistema metrológico de acuerdo a la norma NTE INEN ISO 5725-6 para ensayos de tensión de aceros de baja aleación mediante una celda de carga de 15 toneladas

Abstract

This research project focuses on the importance of metrology in tensile testing of low alloy steels, specifically AISI 4340. The accuracy and precision of measurements are crucial to accurately assess the mechanical properties of these materials, which impacts the safety and durability of structures and products that use them. The NTE INEN ISO 5725-6 standard is established as a fundamental reference framework to guarantee reproducibility and repeatability in tensile tests, which ensures that different laboratories obtain comparable and reliable results when using the same measurement methods and equipment. To ensure that measuring equipment maintains its accuracy over time, it is necessary to implement a metrological assurance system, which includes calibration of the universal testing machine and evaluation of the calibration results. Calibration results that have been certified provide a solid basis for the validity of the tests. The analysis of the tensile tests shows the mechanical variability of AISI 4340 steel. Analysis of variance (ANOVA) is used to evaluate if there are significant differences between the results. This analysis helps to establish intermediate precision limits for future tests, allowing to monitor and verify compliance with the characteristics determined for the material.