冷喷涂Ni-Al-W活性复合材料反应性能研究

Study on Reaction Performance of Ni-Al-W Active Composites Consolidated by Cold Spraying

利用差示扫描量热法(DSC)探究了Ni-Al-W活性复合材料的热反应过程。结果表明,采用冷喷涂制备的NiAl-W活性复合材料在制备过程中没有发生金属间化合反应,只在温度达到450℃时发生了固态扩散反应。W含量对于Ni-Al-W体系的固态扩散反应阈值温度无明显影响。Ni-Al固态扩散反应之后,W开始参与Ni-Al-W体系的固态扩散反应,Al-W反应阈值温度大于Ni-Al反应。四种不同配比的复合材料均在Ni-Al共晶温度时发生热爆反应。随着W含量的升高,在反应中对Al的消耗量也随之增加,从而抑制了Ni Al金属间化合物的形成,降低了体系反应的能量密度。

The thermal properties of Ni-Al-W active composites were analyzed by differential scanning calorimetry(DSC).The results show that there was no intermetallic compound reaction in processing NiAl-W active composite,and the solid state diffusion reaction was found at 450℃.The effect of the content of tungsten on threshold temperature of solid-state diffusion reaction of Ni-Al-W system was negligible.Tungsten started to diffuse in the Ni-Al-W system after Ni-Al solid-state reaction and the threshold temperature of Al-W reaction was higher than that of Ni-Al reaction.When the temperature reached the eutectic temperature of Ni-Al,the explosion reaction was found in all of the four different composites.With increasing content of tungsten,the consumption of aluminum caused by tungsten increased,this inhibited the formation of Ni-Al intermetallic compound and reduced the energy density of the system reaction.