高温下Mn对SiC/Cu界面反应和无压熔渗的影响

Influence of Mn on Interfacial Reaction and Pressureless Infiltration of SiC/Cu at High Temperature

研究了SiC/Mn二元体系反应和SiC/Cu/Mn三元体系反应。评价了利用无压熔渗工艺构建SiC/Cu复合材料的可能性及其利弊。通过XRD和SEM分析,研究了反应过程中的生成物相及其微观形貌。结果表明:Mn和SiC在N2中发生反应,在SiC表面生成了MnSiN_2。SiC的分解随温度的升高而加剧。在1250℃生成的Si_3N_4和石墨C的量很少,而随温度升至1350℃而大幅增加。SiC/Cu/Mn三元体系在1250℃N_2气氛中反应相组成除SiC和Cu外,主要为MnSiN_2和少量Si_3N_4、Cu_3Si以及石墨C。当温度升高至1350℃时,SiC分解严重,Si_3N_4和石墨C大幅增加。纯Cu粉在Mn助渗剂作用下在1350℃实现对SiC骨架的无压熔渗。

The reactions o f SiC/Mn binary system and SiC/Cu/Mn ternary system were researched. The possibility, advantages and disadvantages of using pressureless infiltration method to build SiC/Cu composite were evaluated. The phases generation during the reaction and its micro-morphology were analyzed by X-ray diffraction and scan electron microscope. The results show that Mn reacts with SiC in nitrogen atmosphere and MnSiN2 is generated on the surface of SiC particle. The decomposition of SiC increases with the temperature increasing. The amount of Si3N4 and graphite is less at 1250 ℃, but the amount increases significantly as the temperature increases to 1350 ℃. The main produced phase of SiC/Cu/Mn ternary system reacting at 1250 ℃ in N2 atmosphere is MnSiN2, and some Si3N4, Cu3Si and graphite phases besides SiC and Cu. As the temperature increases to 1350 ℃, SiC decomposes seriously, and the amount of Si3N4 and graphite increases significantly. Under the action of Mn infiltration-aid, pure Cu powder is pressureless-infiltrated into SiC skeleton at 1350 ℃.