Effects of impurity elements on SiC grain boundary stability and corrosion

• 作者: Jun Hui Bao-Liang Zhang Tao Liu Min Liu Wen-Guan Liu
• 来源期刊: 核技术（英文版）
• 年，卷（期）: 2021,（11）
• 所属期刊栏目: NUCLEAR CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR MEDICINE
• 页码范围: 54-72
• 页数: 19页
• 语种: 英文

摘要

Grain boundaries(GBs)have critical influences on the stability and properties of various materials.In this study,first-principles calculations were performed to determine the effects of four metallic impurities(Ni,Al,Bi,and Pb)and three nonmetallic impurities(H,O,and N)on the GBs of silicon carbide(SiC),using the Σ5(210)GBs as models.The GB energy and segregation energy(SE)were calculated to identify the effects of impurities on the GB stability.Electronic interactions considerably influ-enced the bonding effects of SiC.The formation of weak bonds resulted in the corrosion and embrittlement of GBs.The co-segregation of Bi,Pb,and O was also investigated in detail.