An evaluation of durability and mechanical strength in a cement mortar is presented in this work. A slag coming from steelmaking processes has been added to the mortar. This slag has similar properties to the ones of cement, and it has been added to the mortar in different proportions with two sizes of granulometry. With this addition, better properties against the action of sulfates are expected, and therefore, the presence of fracture and wear in the structures can be reduced. This allows more safety and increased life in the mortar, and the most important thing is that, this will contribute to decrease the environmental contamination because the slag used in this work is coming from the industrial waste, which is produced in big amounts in the steel sector worldwide. The studied materials are mortar cubes in which the mechanical strength has been evaluated. The dimensions of the samples are around 50×50×50 mm 3 and, according to the standard ASTM C109, these cubes should be evaluated during 1, 3, 7, 28, 56 and 118 days. The expansion tests to evaluate the sulfates attack is performed according to the standard ASTM C1012, in bars of around 25×25×285 mm 3 . These bars were submerged in water with lime and when the bars obtained a strength bigger than 20 MPa, they were also submerged in a sulfate solution, which was prepared 24 hours earlier with a pH that should be between 6 and 8. In this way, from the point of view of strength to sulfate attack, the mortar durability is evaluated by employing techniques such as X-ray diffraction, X-ray fluorescence and scanning electron microscopy, which allow us to determine the presence of different components that are responsible for the expansion as the formation of gypsum, ettringite, and thaumasite. As a result of this research, it is evident that slag with smaller particle size shows positive behavior against the action of sulfates, thus revealing minimum expansion percentages.

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A magneto-dielectric material composed of a polyester resin-based microstrip (P115A), copper sheets and magnetite powders was designed in concentrations of 10, 20 and 30% Wt and with filters of 200, 325 and 500. The particles were aligned vertically and horizontally during the curing process using 300 mT magnetic fields. From a complete factorial design of 33, 27 microstrip-type circuits of 4 mm width, 70 mm length and 0.93 mm thickness were manufactured, characterized by scanning electron microscopy and vector network analysis. The cross-matrix analysis determined an optimal circuit response from the magneto-dielectric material with a concentration of 20% magnetite and an average particle size of 21.48 μm in horizontal alignment to the applied magnetic field and to the transmission line, obtaining a relative dielectric constant of Er 3.88 with a low dielectric loss of 0.054, within an operating range of 150 KHz to 4 GHz.

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