Akademik Veri Yönetim Sistemi
International Journal of Metalcasting, 2024 (SCI-Expanded)
This study investigated the effect of cerium (Ce) addition (0.5 and 1 wt.-%) on the microstructure, mechanical properties, and dry sliding wear behavior of AM50 magnesium alloy produced by high-pressure die casting (HPDC). A tribometer was utilized to conduct a dry sliding wear test with different sliding speeds (0.5 m.s-1, 1 m.s-1, 1.5 m.s-1, and 2 m.s-1), different loads (5N, 10N, and 20N), and a constant sliding distances (200 m). The microstructural characterization was conducted using optical microscopy, scanning electron microscopy (SEM), and energy-dispersive X-ray analysis (EDX). The tensile and hardness tests were performed to evaluate the mechanical properties. The α-Mg grain size decreased from 40 µm to 26 µm with the addition of up to 1 wt.-% Ce. Cerium incorporation led to the formation of γ-Al11Ce3 needle-like shape, and the presence of Al10Ce2Mn7 spheroidal shape intermetallics was observed when Ce was added to the AM50 magnesium alloy. Adding 1 wt.-% Ce increased the tensile yield strength from 87 MPa to 98 MPa, the ultimate tensile strength from 141 MPa to 168 MPa, and the hardness from 38 HV to 45 HV. Incorporating Ce into AM50 magnesium alloy lowers the coefficient of friction and wear rate under dry sliding wear tests. It has been noted that volume loss generally increases with higher sliding speeds. However, incorporating Ce content mitigates this effect by reducing wear, primarily due to the formation of protective CeO oxides that function as lubricants. Under severe wear testing conditions (20N load and 2 m.s-1 sliding speed), the AM50+1Ce sample demonstrated the lowest volume loss and wear rate. Conversely, the AM50 sample exhibited the highest wear rate, weight loss, and coefficient of friction (μ = 0.447). The worn surfaces displayed signs of abrasion, oxide formation, and noticeable wear grooves. The primary wear mechanisms observed in all samples were abrasion, oxidation, and microplastic deformation.