Investigating the Effect of Fly Ash Addition on the Metallurgical and Mechanical Behavior of Al-Si-Mg-Cu Alloy for Engine Cylinder Head Application

Abstract

The authors researched the physical, metallurgical, and mechanical characteristics of A354 alloy (Al-Si-Mg-Cu) reinforced with 5, 10, and 15 wt% of fly ash metal matrix composites. A baseline alloy and three composites were fabricated by a liquid metallurgy route and poured into a permanent mold to obtain cast rods of dimension Φ32 mm × 156 mm. The metallurgical characterization of the developed alloy and metal matrix composites was conducted using energy-dispersive spectroscopy (EDS), field-emission scanning electron microscopy (FESEM), and X-ray diffraction. All the developed composites showed a pore-free nature, but only A354 alloy reinforced with 5 wt% of fly ash (AF5) possessed a homogeneous distribution and perfect bonding of the fly ash with the A354 matrix. Therefore, transmission electron microscopy (TEM) analysis was performed on the sample AF5. All developed alloys and metal matrix composites were subjected to hardness and mechanical property tests. It was observed that the AF5 sample had 170 ± 5.6 HV and tensile strength of 216 ± 2.3 MPa, 18.8% and 24.8% higher than the A354 matrix, but the ductility (6.5 ± 0.43%) was reduced by 23% from the baseline alloy. Finally, the fractography analysis was conducted on all the samples using FESEM to analyze the fracture mode. The fabricated 5 wt% fly ash-based metal matrix composite showed better mechanical performance than other samples. Hence, sample AF5 is suggested for manufacturing components in automotive and structural parts.

Investigating the Effects of Advanced Heat Treatment Techniques on the Mechanical Properties of Cast Components

“…The hardness of the cast components increased after the heat treatment processes, with the highest values observed for the components treated with cryogenic treatment. This can be attributed to the transformation of retained austenite to martensite, which results in a more uniform and stable microstructure [27][28][29][30]. The increase in hardness can enhance the wear resistance of the components, thereby extending their service life.…”

Alumínio – uma análise do seu contexto histórico, da reciclabilidade à transmissão energética

“…O alumínio é um metal abundante que possui boa condutividade elétrica e térmica, sendo também um metal leve e apresentando ótima resistência à corrosão (Milani e Timelli, 2023). Ele é muito útil e as suas ligas podem ser utilizadas, por exemplo, para fundir peças de automóveis, ou para substituir o ferro fundido (Shankar et al, 2022). De acordo com Kasińska et al (2021), em média, 70% das ligas de alumínio, após a reciclagem, são usadas para peças fundidas da indústria automotiva.…”