Wu Zongxu, Wang Haoran, Chen Zhaoke, Zhang Ruiqian, Wen Qingbo, He Zongbei, Li Ming, Xiong Xiang
Science and Technology on High Strength Structural Materials Laboratory, Central South University, Changsha 410083, China.
State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China.
Materials (Basel). 2022 Apr 15;15(8):2900. doi: 10.3390/ma15082900.
This study aimed to study the effects of different catalyst introduction methods on the distribution of SiC nanowires (SiCNWs) and the mechanical properties of SiC/SiC composites. Two different catalyst-introduction methods (electroplating (EP) vs. atomic deposition (AD)) have been used to catalyze the growth of SiC nanowires in SiC preforms. The morphology, structure and phase composition were systematically investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The SiCNWs-reinforced SiC/SiC composited was densified by CVI. The compressive strength of the SiCNWs-reinforced SiC/SiC composites was evaluated by radial crushing test. Compared with EP, atomic Ni catalysts fabricated by AD have higher diffusivity for better diffusion into the SiC preform. The yield of SiCNWs is effectively increased in the internal pores of the SiC preform, and a denser network forms. Therefore, the mechanical properties of SiCNW-containing SiC/SiC composites are significantly improved. Compared with the EP-composites and SiC/SiC composites, the compressive strength of AD-composites is increased by 51.1% and 56.0%, respectively. The results demonstrate that the use of AD method to grow SiCNWs is promising for enhancing the mechanical properties of SiC/SiC composites.
本研究旨在研究不同催化剂引入方法对SiC纳米线（SiCNWs）分布及SiC/SiC复合材料力学性能的影响。采用两种不同的催化剂引入方法（电镀（EP）与原子沉积（AD））来催化SiC预制体中SiC纳米线的生长。利用扫描电子显微镜（SEM）、透射电子显微镜（TEM）和X射线衍射（XRD）对其形貌、结构和相组成进行了系统研究。通过化学气相渗透（CVI）对SiCNWs增强的SiC/SiC复合材料进行致密化处理。通过径向挤压试验评估SiCNWs增强的SiC/SiC复合材料的抗压强度。与电镀法相比，通过原子沉积法制备的镍催化剂具有更高的扩散率，能更好地扩散到SiC预制体中。SiC预制体内孔中SiCNWs的产率有效提高，并形成更致密的网络。因此，含SiCNWs的SiC/SiC复合材料的力学性能得到显著改善。与电镀法复合材料和SiC/SiC复合材料相比，原子沉积法复合材料的抗压强度分别提高了51.1%和56.0%。结果表明，采用原子沉积法生长SiCNWs对提高SiC/SiC复合材料的力学性能具有广阔前景。
