Research Information System
International Journal of Metalcasting, vol.18, no.3, pp.2283-2297, 2024 (SCI-Expanded)
The study added Mn at different rates to the Al–Si–Mg eutectic alloy and heat-treated the quaternary alloy. Therefore, the microstructure morphology of the Al–Si–Mg eutectic alloy was examined after Mn addition and heat treatment. Also determined were the hardness, tensile strength, fracture surface analysis, and thermoelectric characteristics of the newly produced Al–12.95%Si–4.96%Mg–X%Mn [X=0.5, 1.0, and 1.5 (wt.)] alloys. Along with the predicted Si and Mg2Si phases in the Al matrix phase, this investigation found a randomly distributed Mn-rich Al15Mn3Si2 intermetallic phase and a Mg-rich Al5Si3Mg2 phase. Mn-doped samples without heat treatment were somewhat softer than the parent alloy. After heat treatment, the hardness more than doubled for the Al–Si–Mg eutectic system and Mn-doped samples. After heat treatment, the alloy with 1.5% Mn added had the maximum hardness value of 94.3±5.0 HV. Heat treatment improved tensile strength by up to 80%, and the alloy with 0.5% Mn had 144.7 MPa. Melting temperatures (Tm) (K), fusion enthalpy (ΔH) (J/g), and specific heat Cpl (J/gK) were determined for non-heat-treated materials. The 0.5, 1.0, and 1.5 Mn-added samples had Tm of 566.30, 568.96, and 566.40 °C, respectively. The ΔH value of samples with 0.5%, 1.0% and 1.5% Mn addition is 662.29, 657.93 and 639.11, respectively. Cpl was 0.788, 0.781, and 0.761 J/g.K. for 0.5%, 1.0%, and 1.5% Mn-added samples. In both heat-treated and non-heat-treated samples, Mn enhanced electrical resistance.