Magnesium and its alloys have unique advantages to act as resorbable bone fixation materials, due to their moderate mechanical properties and biocompatibility, which are similar to those of human tissue. However, early resorption and insufficient mechanical strength are the main problems that hinder their application. Herein, the effects of microstructure transformation on the mechanical properties and corrosion performance of Mg-Zn-Mn-Ca were investigated with electrochemical and immersion measurements at 37 °C in a simulated body fluid (SBF). The results showed that the number density of Ca₂Mg₆Zn₃/Mg₂Ca precipitates was remarkably reduced and grain sizes were gradually increased as the temperature increased. The alloy that received the 420 °C/24 h treatment demonstrated the best mechanical properties and lowest corrosion rate (5.94 mm/a) as well as presented a compact and denser film than the others. The improvement in mechanical properties could be explained by the eutectic compounds and phases (Mg₂Ca/Ca₂Mg₆Zn₃) gradually dissolving into a matrix, which caused severely lattice distortion and facilitated structural re-arrangement of the increased Ca solute. Moreover, the difference in potential between the precipitates and the matrix is the main essence for micro-galvanic corrosion formation as well as accelerated the dissolution activity and current exchange density at the Mg/electrolyte interface. As a result, the best Mg alloys corrosion resistance must be matched with a moderate grain size and phase volume fractions.

镁及其合金具有适度的机械性能和生物相容性，具有与人体组织相似的独特优势，可作为可吸收的骨固定材料。但是，早期吸收和机械强度不足是阻碍其应用的主要问题。本文中，通过在模拟体液（SBF）中在37°C下进行电化学和浸没测量，研究了微结构转变对Mg-Zn-Mn-Ca力学性能和腐蚀性能的影响。结果表明，Ca ₂ Mg ₆ Zn ₃ / Mg ₂的数密度随着温度的升高，Ca沉淀物显着减少，晶粒尺寸逐渐增加。经过420°C / 24 h处理的合金表现出最佳的机械性能和最低的腐蚀速率（5.94 mm / a），并且呈现出比其他合金更致密和致密的膜。力学性能的改善可以通过共晶化合物和相（Mg ₂ Ca / Ca ₂ Mg ₆ Zn ₃）逐渐溶解成基质，这会导致严重的晶格畸变并促进增加的Ca溶质的结构重排。而且，析出物与基体之间的电势差是形成微电流腐蚀的主要要素，并加速了Mg /电解质界面的溶解活性和电流交换密度。结果，最好的镁合金耐腐蚀性必须与适度的晶粒尺寸和相体积分数相匹配。