Investigación de los atributos mecánicos, de desgaste y térmicos de la síntesis de nanocom-puestos de aluminio y circonio mediante el proceso de metalurgia en polvo

This article reports the results of a study that examined the wear and thermal behavior of Al/ZrO2 nanocomposites fabricated using powder metallurgy with different ZrO₂ reinforcement contents (3, 6, and 9 wt.%). The findings show that microhardness increased to 33 HV in sample AZ0, 58 HV in AZ3, 74 HV in AZ6, and 87 HV in AZ9, indicating that higher ZrO2 content leads to enhanced surface resistance. The tensile strength of sample AZ0 was 285 MPa, with elongation values decreasing to 6%, which demonstrates a transition from more ductile performance to increased mechanical strength with the addition of reinforcement material. Compressive strength also exhibited a significant improvement, increasing from 43 MPa in AZO to 376 MPa in AZ9, indicating enhanced load-bearing capacity in the reinforced composite. The coefficient of friction decreased markedly from 1.6 to 0.4, reflecting improved wear resistance due to the homogeneous distribution of ZrO2 nanoparticles and the formation of a hard ceramic phase. Thermal conductivity also decreased from 237 Wm−1K−1 to 150 Wm−1K−1, which is attributed to the low thermal conductivity of ZrO2 and its homogeneous incorporation into the matrix. Similarly, the coefficient of linear thermal expansion decreased from 22x10-6/K to 11x10-6/K, owing to the thermal barrier effect and dimensional stability provided by the ceramic reinforcement. Overall, these results demonstrate that ZrO2 nanoparticles have the potential to enhance the mechanical strength, wear resistance, and thermal stability of aluminum nanocomposites.