Manufacturing of Mg-Al5TiB composite and addition of nano-sized Al2O3 through stir casting method with T6 heat treatment temperature variation

Abstract

In order to find aluminium replacement for vehicle structure and also application of automotive components, the research on Mg-Al-Ti-B composite was performed in this work. The composite of magnesium is highly compatible to be applied in vehicle body structure because of its low weight and density. Therefore, the lightweight of vehicle body structure, great mechanical properties, and high efficiency can be obtained. Mg-Al-Ti-B serves as the matrix, and 0.20 vf% of nano-sized Al2O3 is applied as the reinforcement. The composite of Mg-Al-Ti-B was produced through a stir casting process. Hereafter, T6 heat treatment was employed with variation of aging temperature, such as 170 °C, 200 °C, 230 °C and 260 °C for 6 h, subsequent the previous 1 h, 420 °C for the treatment of solution. The T6 heat treatment impact on microstructure indicates a different morphology of primary Mg17Al12 in which spheroidization occurs, the precipitation of Al3Ti and TiB2 are also observed from the aging process. In this work, OM, EDS, XRD, OES, density and porosity measurements, as well as destructive tests were performed for the characterization. The T6 heat treated sample’s mechanical properties were rectified than the non-heat treated ones. The highest ultimate tensile strength was obtained with 65.31 MPa at 170 °C aging temperature. The optimum value of hardness, impact value and wear rate are observed at 200 °C aging temperature, the values are 92.4 HRH, 0.07 J/mm2 and 0.00254 mm3/m, respectively.