【摘要】 采用座滴法研究了反应烧结SiC/Co-Cr体系的润湿性。与反应烧结SiC/纯Co体系进行对比,研究了Cr含量、实验温度和保温时间对润湿角的影响及活性元素的作用。结果表明,加入适量的活性元素Cr能够显著提高体系的润湿性。当体系的Cr含量分别为5%,7%和42%时,体系的润湿角较小,润湿性比较好。SiC/Co-Cr体系和SiC/纯Co体系的润湿过程均属于反应性润湿,实验温度和保温时间对体系的润湿角影响较大。微观结构研究和XRD分析表明,对于SiC/纯Co体系,界面区域发生了化学反应,生成了CoSi,减小了润湿角。加入活性元素Cr以后,由于Cr元素与基体发生反应,生成Cr23C6,进一步降低了体系的界面能,提高了润湿性。更多还原

【Abstract】 The wettability of a reaction bonded SiC/Co-Cr system was studied by the sessile drop technique in high vacuum.The effect of Cr content and technological parameters including wetting temperature and dwelling time on the wettability of the system was investigated.Compared with the reaction bonded（RB） SiC/pure Co system,the wettability of the system is remarkably improved by adding active element Cr.The relatively small contact angles of the RB SiC/Co-Cr system are obtained with the Cr content of 5%,7% and 42%,respectively.Wetting temperature and dwelling time strongly affect the contact angle.The experimental results show that the wetting processes of both RB SiC/pure Co system and RB SiC/Co-Cr system belong to reactive wetting.Microstructure study and XRD phase analysis indicate that interfacial reactions take place in the RB SiC/pure Co system,leading to the formation of CoSi,and resulting in the decreasing of the contact angle;but for the RB SiC/Co-Cr system,interfacial reactions cause the formation of Cr₂3C₆,leading to the decreasing of the interfacial energy of the system,and consequently the wettability of the system is improved.更多还原