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采用座滴法研究了真空、1800℃下NiAl在碳、TiC、SiC和ZrC上的润湿性,并通过铺展实验和熔渗实验优化了NiAl改性C/C复合材料的活性添加元素及添加量。采用真空熔渗法制备NiAl改性C/C复合材料,采用X射线衍射仪和扫描电镜分析了复合材料的微观结构和渗透机制。结果表明,NiAl与C或SiC的润湿性较差,与TiC或ZrC的润湿性很好;添加Ti能改善NiAl和C的润湿性,Ti粉含量为15%(质量分数)时,C/C复合材料熔渗NiAl的效果最佳,NiAl渗透层的厚度为0.8~0.9 mm;添加Ti利于C/C复合材料渗NiAl的主要原因是Ti与C反应形成TiC,改善了NiAl在C/C复合材料中的化学吸附和物理吸附特性,NiAl通过毛细管力作用渗入到C/C复合材料坯体中。
The droplet method was used to study the wettability of NiAl at 1800 ℃ under carbon, TiC, SiC and ZrC. The active addition elements and additions of NiAl modified C / C composites were optimized by spreading experiments and infiltration experiments the amount. NiAl modified C / C composites were prepared by vacuum infiltration method. The microstructure and infiltration mechanism of the composites were analyzed by X-ray diffraction and scanning electron microscopy. The results show that the wettability of NiAl with C or SiC is poor and the wettability with TiC or ZrC is very good. Adding Ti can improve the wettability of NiAl and C. When Ti content is 15% (mass fraction) The effect of infiltration of NiAl on C / C composites is best, and the thickness of NiAl infiltration layer is 0.8-0.9 mm. The main reason for adding Ti to infiltrating NiAl in C / C composites is the reaction of Ti with C to form TiC and the improvement of NiAl in C / C composites in the chemical adsorption and physical adsorption characteristics, NiAl through the capillary force into the C / C composite body.