镁合金作为生物植入材料的应用已受到广泛关注。本论文以合金制备的纯净化为切入点，选取对人体无毒害、制造成本较低、且生物相容性较好的Zn元素采用气相合金化方法制备高纯Mg-Zn二元合金，并对制备出的合金进行后续的热处理和热压处理，研究其对Mg-Zn二元合金组织和性能的影响。主要研究结果如下： (1) 冷凝态Mg-Zn合金显微组织由椭圆形α-Mg和多边形共晶混合物组成，共晶混合物由MgZn和Mg7Zn3相组成，并呈片层状和针状两种典型形态。T4处理后Mg7Zn3、MgZn2大量分解而MgZn相增加，物相尺寸变大； T6处理后， Mg-Zn二元合金内形成由α-Mg和Mg7Zn3组成的树枝状组织，物相尺寸减小且组织分布较为均匀。随着T4温度和时间的增加，Mg-Zn二元合金的硬度增加，此时的强化机理为固溶强化；T6处理后，由于时效后的组织分布均匀，时效强化机理占主导地位且硬度有所提高。 (2) 经T4:340℃+24h后合金的自腐蚀电位由冷凝态的-1468.8mV升高到-1267.1mV而腐蚀电流密度减小到134.47μA•cm2，Rct的值不断增加，从冷凝态时的128.70 Ω•cm2增加到T4:340℃+24h后的216.31 Ω•cm2；经T6处理后其自腐蚀电位又降低到-1535.4mV，腐蚀电流密度增加到685.00μA•cm2，且 Rct显著减小，仅为26.55Ω•cm2。即固溶处理提高了Mg-Zn合金在Ringer’s液中的耐蚀性，而时效处理后耐蚀性显著降低。 (3) 随着热压时间和温度的增加，组织分布愈加均匀且共晶组织细化，共晶混合物的含量减少，在420℃下热压8h时，合金组织已完全变成扁平状，同时伴有第二相的析出和弥散分布。热压使得组织尺寸发生细化且第二相弥散分布此时的强化机理为细晶强化和时效强化的共同协同作用。 (4) 在320℃、10MPa的条件下，随着时间从4h增加到12h，合金在腐蚀液中的腐蚀电流密度从56.19μA•cm2增加到175.56μA•cm2，而电荷转移电阻从295.1Ω•cm2减少到30.2Ω•cm2；而在10MPa下热压40min，随着热压温度从300℃升高到360℃，腐蚀电流密度从90.51μA•cm2减小到30.05μA•cm2，同时电荷转移电阻从38.39Ω•cm2增加到515.13Ω•cm2，合金的耐蚀性能随着热压温度的升高而提高。 (5) 冷凝态Mg-Zn二元合金的腐蚀形貌以局部腐蚀为主，T4处理后变为一定程度的全面腐蚀，而T6处理之后点腐蚀密度较大，经过热压后腐蚀产物沿特定方向分布。不同处理后合金的失重率不断增大但腐蚀速率不断变小。随着腐蚀的进行，溶液的pH值前期在增加，后期稳定于10.5。固溶处理和热压处理使合金表面的腐蚀产物膜层发生变化，从而对合金起到保护作用。

Magnesium alloys have attracted wide attention as biomaterials. In this study, the purification of alloy processing is taken into consideration, and the high purity Mg-Zn binary alloy is prepared by gas-phase alloying with Zn which has less harm to human body, low manufacturing cost and good biocompatibility. The subsequent heat treatments and hot pressing processes were carried out to study the effects on the microstructure and properties of Mg-Zn binary alloy. The main research contents are as followed: (1) The microstructure of Mg-Zn binary alloys by gas-phase alloying is composed of elliptical α-Mg and polygonal eutectic mixtures, which are composed of MgZn and Mg7Zn3 phases, and show two typical morphologies: lamellar and rods-like. After T4 treatment, Mg7Zn3 and MgZn2 decompose extensively, while the amount of MgZn phase increased and the size of stuctures and phases of the alloy increased too. After T6 treatment, dendritic structure was formed in Mg-Zn binary alloy, with a large number ofα-Mg and Mg7Zn3, and the phase size decreases and the structure distribution is more uniform. With the increase of T4 temperature and time, the hardness of Mg-Zn binary alloy increased, and the strengthening mechanism is solution strengthening. After T6 treatment, the aging strengthening mechanism dominated and the hardness increased due to the homogeneous distribution of aged structure. (2) The corrosion potential of Mg-Zn alloy increases from -1468.8mV at condensate state to -1267.1 mV and the corrosion current density decreases to 134.47μA•cm2 24 hours after solution at 340℃. After T6 treatment, the self-corrosion potential decreases to -1535.4mV and the corrosion current density increases to 685.00μA•cm2. Rct values continue to increase, from 128.70Ω•cm2 in the condensate state to 216.31Ω•cm2 at T4 state, and after T6 treatment it significantly decreased to only 26.55Ω•cm2.That is to say, solution treatment improves the corrosion resistance of Mg-Zn alloy in Ringer's solution, while the corrosion resistance decreases significantly after aging treatment. (3) With the increase of hot pressing time and temperature, the structure distribution becomes more uniform and the eutectic structure fines, and the content of eutectic mixture decreases. When hot pressing for 8 hours at 420℃, the alloy structure has completely become flat, accompanied by precipitation and dispersion of the second phase. When the hot pressing makes the structure size finer and the second phase disperses, the strengthening mechanism is the synergistic effect of fine grain strengthening and aging strengthening. (4) The corrosion current density of the alloy increased from 56.19μA•cm2 to 175.56μA•cm2, and the charge transfer resistance decreased from 295.1Ω•cm2 to 30.2Ω•cm2 with the increase of time from 4h to 12h at 320℃, 10 MPa. The corrosion current density decreased from 90.51μA•cm2 to 30.05μA•cm2 and the charge transfer resistance increases from 38.39Ω•cm2to 515.13Ω•cm2 as the hot pressing temperature rised from 300℃ to 360℃ at 10 MPa for 40 min. (5) The corrosion morphology of condensed Mg-Zn binary alloys is mainly local corrosion. After T4 treatment, the corrosion morphology changed to a certain degree of overall corrosion, while after T6 treatment, the pitting corrosion density is higher, and the corrosion products distribute along a specific direction after hot pressing. After different treatments, the weight loss rate of the alloy increased but the corrosion rate decreased. With the corrosion proceeding, the pH value of the solution increased in the early stage and tended to stabilize at 10.5 Solution treatment and hot pressing can change the passive film on the surface of the alloy and protect the alloy.