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In this study, four different Mg-Zn-Ca-Mn alloys were produced using gravity die casting method. Mn content was kept constant in all alloys, while Zn and Ca were added in two different ratios. Homogenization heat treatment was applied to all cast alloys and a specimen from each homogenized alloy was hot rolled. Microstructure, mechanical properties, and corrosion behavior of the homogenized and hot rolled alloys were investigated as comparatively. Following results were obtained; grain size decreased significantly with increasing Zn content, Zn promoted Ca2Mg6Zn3 phase formation, corrosion resistance increased with increasing Zn/Ca atomic ratio, hot rolling resulted in much higher tensile strength but much lower ductility and toughness. Among the homogenized and hot rolled alloys, ZXM300-h alloy (hot rolled ZXM300 alloy) with its 146 ± 2.5 MPa yield strength, 229 ± 3.7 MPa tensile strength,% 1.6 ± 0.1 elongation and 0.029 mm/yr. immersion corrosion rate exhibited the best mechanical properties and corrosion resistance to be used as a biodegradable alloy such as fracture bone plate material.

In this study, as-cast Mg, ZXM100 (1.07Zn–0.21Ca–0.31Mn) and ZXM120 (1.01Zn–1.63Ca–0.30Mn) alloys were produced by gravity die casting method, and microstructure, phase analysis, corrosion and mechanical properties of the alloys were investigated comparatively in order to develop degradable Mg-based biomaterials with improved properties. It is observed that Ca2Mg6Zn3 phase is expected to be present in ZXM100 (1.07Zn–0.21Ca–0.31Mn) alloy totally dissolved in the α-Mg matrix after homogenization heat treatment. However, Mg2Ca phase is expected to be present in ZXM100 (1.07Zn–0.21Ca–0.31Mn) alloy partially dissolved in the α-Mg matrix. Results showed that ZXM100 alloy has a much more homogeneous structure, a better performance, higher corrosion resistance and mechanical properties than those of as-cast Mg and ZXM120 alloy. ZXM100 (0.099 mm/year) alloy has a three times slower corrosion rate than ZXM120 (0.294 mm/year) alloy. It is found that the ZXM100 alloy has closer values to the desired corrosion rate and mechanical properties as a biodegradable implant material.

In this study, Mg was alloyed with Zn and Ca to produce six different Mg–Zn–Ca alloys (designated as ZX alloys) by the gravity die casting method. Zn contents of the alloys were 1 wt., 3 wt., and 5 wt.% and Ca contents of the alloys were 0.2 wt. and 1.8 wt.%. Homogenization heat treatment was applied to all cast alloys. After that, a part of each homogenization heat-treated alloys was hot-rolled. Microstructure, mechanical properties, electrochemical and immersion corrosion behaviors at simulated physiological conditions of the heat-treated and hot-rolled alloys were compared. Increasing the amount of alloying elements (Zn and Ca) in Mg reduces grain size and improves the hardness. It was seen that the microstructure consisted of α-Mg as a matrix phase and intermetallic phases: Mg2Ca phase for the alloy having Zn/Ca = 0.37 (ZX12) and Ca2Mg6Zn3 phase for the other alloys. When the mechanical properties and corrosion rates of homogenized and hot-rolled alloys were compared, it was seen that hot-rolled ZX10-h (Mg-0.94Zn-0.16Ca) alloy can be considered as a fracture bone fixation plate material with its acceptable properties: 121 ± 2.1 MPa yield strength, 226 ± 3.7 MPa tensile strength, % 4.1 ± 0.2 elongation, and 0.062 mm/year immersion corrosion rate.

In this study; Hybrid composites containing different proportions of TiB2 and graphene were produced using the pressure infiltration method. Inert SF6 gas is used to prevent oxidation in the productions. While 8 bar infiltration pressure was provided by argon gas, the infiltration temperature was chosen as 800°C. The corrosion behaviors of the compos-ite materials were examined. Corrosion resistance was determined by potentiodynamic and immersion corrosion testing in 3.5% NaCl solution. In addition, SEM examinations were conducted to understand the corrosion mechanisms. At the end of the measurements, the highest porosity was measured as %4,7 in composite containing 1% graphene compared to pure matrix and composite containing only TiB2. The added reinforcement (TiB2 and Graphene) elements cause decreases in corrosion resistance. The highest corrosion resist-ance was achieved in AZ91 alloys.

In this study, Mg was alloyed with Zn and Ca to produce six different Mg-Zn-Ca alloys (designated as ZX alloys) by the gravity die casting method. Zn contents of the alloys were 1 wt., 3 wt., and 5 wt.% and Ca contents of the alloys were 0.2 wt. and 1.8 wt.%. Homogenization heat treatment was applied to all cast alloys. After that, a part of each homogenization heat-treated alloys was hot-rolled. Microstructure, mechanical properties, electrochemical and immersion corrosion behaviors at simulated physiological conditions of the heat-treated and hot-rolled alloys were compared. Increasing the amount of alloying elements (Zn and Ca) in Mg reduces grain size and improves the hardness. It was seen that the microstructure consisted of α-Mg as a matrix phase and intermetallic phases: Mg