Huang Yong, Wu Weisong, Cong Shuo, Ran Guang, Cen Danxia, Li Ning
College of Energy, Xiamen University, Xiamen 361102, China.
College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361102, China.
Materials (Basel). 2018 Aug 23;11(9):1509. doi: 10.3390/ma11091509.
The effect of the strain rate, experimental temperature, Zn content in the test solution, and prefilming time on the mechanical properties was investigated by a tensile test with a slow strain rate, at a chemical solution of 2.2 ppm Li and 1200 ppm B in a static autoclave with 8.2 MPa. The experimental parameters clearly affected the tensile properties. The surface morphology, fractograph, and cross-sectional microstructure were analyzed by scanning electron microscopy and transmission electron microscopy. The (elongation) and UTS (ultimate tensile strength) of the samples tested in chemical solution were obviously lower than those of the samples tested under a nitrogen atmosphere. However, in general, all samples showed a ductile fracture characteristic and an excellent tensile property in all experimental conditions. The and UTS were first increased with increasing Zn content, and then decreased at both conditions of 9.26 × 10/s and 4.63 × 10/s strain rates. The difference values of tensile properties at different strain rates showed fluctuations with increasing Zn content. The increased with both increasing experimental temperature and prefilming time. The UTS first decreased with increasing prefilming time and then increased. The (stress corrosion cracking susceptibility) decreased with an increasing strain rate, experiment temperature, and prefilming time. Many particles with polyhedrons were formed on the sample surfaces, which was attributed to corrosion in a periodical location at the sample surface. The average length of the particles decreased with increasing Zn content, but increased with both increasing experimental temperatures and prefilming time. The corresponding mechanism is also discussed in this work.
通过在含有2.2 ppm锂和1200 ppm硼的化学溶液中、8.2 MPa的静态高压釜内进行慢应变速率拉伸试验，研究了应变速率、实验温度、测试溶液中的锌含量以及预成膜时间对力学性能的影响。实验参数明显影响拉伸性能。通过扫描电子显微镜和透射电子显微镜分析了表面形貌、断口形貌和横截面微观结构。在化学溶液中测试的样品的伸长率和极限抗拉强度明显低于在氮气气氛中测试的样品。然而，总体而言，所有样品在所有实验条件下均表现出韧性断裂特征和优异的拉伸性能。伸长率和极限抗拉强度首先随锌含量的增加而增加，然后在9.26×10⁻⁶/s和4.63×10⁻⁶/s应变速率条件下均下降。不同应变速率下拉伸性能的差值随锌含量的增加呈现波动。伸长率随实验温度和预成膜时间的增加而增加。极限抗拉强度首先随预成膜时间的增加而下降，然后增加。应力腐蚀开裂敏感性随应变速率、实验温度和预成膜时间的增加而降低。样品表面形成了许多多面体颗粒，这归因于样品表面周期性位置的腐蚀。颗粒的平均长度随锌含量的增加而减小，但随实验温度和预成膜时间的增加而增加。本文还讨论了相应的机理。
