In this present study AZ91D magnesium alloy and AZ91D–5SiC–1Gr (wt%) hybrid metal matrix composite were produced through the stir casting process. Microstructural studies were carried out through X-ray diffraction (XRD), scanning electron microscope (SEM) and SEM with energy-dispersive X-ray analysis (EDAX). XRD study indicated the spinel crystal structure with double substitution of cubic and hexagonal closed pack materials. Ageing heat treatment comprising natural ageing (T4) and artificial ageing (T6) for 24 h was carried out on the materials. Both T4 and T6 heat-treated samples exhibited higher hardness than as-cast samples. Maximum hardness 88.8 ± 2.3 BHN and 129.9 ± 3.27 BHN were obtained for T6 heat-treated alloy and hybrid composite, respectively. Tensile properties of samples were evaluated by their stress–strain curves. Maximum values of ultimate tensile strength, yield strength (0.2%) and ductility obtained for T6 heat-treated hybrid composite were 193 MPa, 87.1 MPa and 11%, respectively. Corrosion behaviour of the samples was evaluated by the electrochemical polarization curves obtained through Tafel extrapolation method. Both the alloy and hybrid composite exhibited improved corrosion resistance as a result of natural ageing (T4) and artificial ageing (T6) heat treatment processes. Lowest corrosion rates 0.071 mm/year and 0.074 mm/year were obtained for AZ91D alloy and AZ91D–5SiC–1Gr (wt%) hybrid composite, respectively.

在本研究中，AZ91D 镁合金和 AZ91D-5SiC-1Gr (wt%) 混合金属基复合材料是通过搅拌铸造工艺生产的。通过 X 射线衍射 (XRD)、扫描电子显微镜 (SEM) 和具有能量色散 X 射线分析 (EDAX) 的 SEM 进行微观结构研究。XRD 研究表明尖晶石晶体结构具有立方和六方封闭堆积材料的双重取代。对材料进行自然时效（T4）和人工时效（T6）时效热处理24 h。T4 和 T6 热处理样品均表现出比铸态样品更高的硬度。T6 热处理合金和混合复合材料的最大硬度分别为 88.8 ± 2.3 BHN 和 129.9 ± 3.27 BHN。样品的拉伸性能通过其应力-应变曲线进行评估。T6 热处理混合复合材料的极限拉伸强度、屈服强度 (0.2%) 和延展性的最大值分别为 193 MPa、87.1 MPa 和 11%。通过Tafel外推法获得的电化学极化曲线评估样品的腐蚀行为。由于自然时效 (T4) 和人工时效 (T6) 热处理工艺，合金和混合复合材料均表现出更高的耐腐蚀性。AZ91D 合金和 AZ91D–5SiC–1Gr (wt%) 混合复合材料的最低腐蚀速率分别为 0.071 毫米/年和 0.074 毫米/年。通过Tafel外推法获得的电化学极化曲线评估样品的腐蚀行为。由于自然时效 (T4) 和人工时效 (T6) 热处理工艺，合金和混合复合材料均表现出更高的耐腐蚀性。AZ91D 合金和 AZ91D–5SiC–1Gr (wt%) 混合复合材料的最低腐蚀速率分别为 0.071 毫米/年和 0.074 毫米/年。通过Tafel外推法获得的电化学极化曲线评估样品的腐蚀行为。由于自然时效 (T4) 和人工时效 (T6) 热处理工艺，合金和混合复合材料均表现出更高的耐腐蚀性。AZ91D 合金和 AZ91D–5SiC–1Gr (wt%) 混合复合材料的最低腐蚀速率分别为 0.071 毫米/年和 0.074 毫米/年。