Huang Song-Jeng, Li Chuan, Feng Jun-Hang, Selvaraju Sivakumar, Subramani Murugan
Department of Mechanical Engineering, National Taiwan University of Science and Technology, Taipei 106336, Taiwan.
Department of Biomedical Engineering, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan.
Materials (Basel). 2024 Apr 16;17(8):1836. doi: 10.3390/ma17081836.
A new Mg-4Zn X Ti-6Al-4V (TC4, of 0, 1, and 3 wt.%) alloy was successfully fabricated by a simple and low-cost gravity casting method and heat treatment at 150 °C for 24 h. The composite was examined by XRD, uniaxial tests, FESEM/EDS, potentiostat/EIS, and immersion tests for the material's microstructures, mechanical properties, electrochemical characteristics, and corrosion resistance. Experimental results indicate that heat treatment enables the precipitation of Zn along the Mg grain boundaries and drives the co-precipitation of Al around the TC4 particles and nearby grain boundaries. Uniaxial tensile tests reveal that TC4 reinforces the Mg-Zn matrix material with higher elastic modulus, ultimate tensile stress, and toughness. The heat treatment further enhanced these mechanical properties. Electrochemical tests show that 1 wt.% TC4 composite exhibits the highest open circuit potential among all tested samples, which implies the 1 wt.% TC4-added Mg-Zn is better resistant to the oxidation of the essential metals Mg, Zn, and Al. The immersion tests in the HBSS solution further show that the 1 wt.% TC4 composite has the lowest rise of pH values after 14 days, and EDS for the corroded surface signifies that Mg is the main element vulnerable to oxidation by corrosion.
一种新型的Mg-4Zn X Ti-6Al-4V（TC4，含量为0、1和3 wt.%）合金通过简单且低成本的重力铸造法成功制备，并在150°C下进行了24小时的热处理。通过X射线衍射（XRD）、单轴试验、场发射扫描电子显微镜/能谱仪（FESEM/EDS）、恒电位仪/电化学阻抗谱（EIS）以及浸泡试验对该复合材料的微观结构、力学性能、电化学特性和耐腐蚀性进行了检测。实验结果表明，热处理能够使锌沿镁晶界析出，并促使铝在TC4颗粒周围和附近晶界处共析出。单轴拉伸试验表明，TC4增强了Mg-Zn基体材料，使其具有更高的弹性模量、极限拉伸应力和韧性。热处理进一步提高了这些力学性能。电化学测试表明，在所有测试样品中，添加1 wt.% TC4的复合材料具有最高的开路电位，这意味着添加1 wt.% TC4的Mg-Zn对主要金属镁、锌和铝的氧化具有更好的抗性。在汉克斯平衡盐溶液（HBSS）中的浸泡试验进一步表明，添加1 wt.% TC4的复合材料在14天后pH值的上升幅度最小，腐蚀表面的能谱分析表明镁是易被腐蚀氧化的主要元素。
