Si_3N_4/Ni和Si_3N_4/Ni_3Al的界面固相反应

使用扫描电子显微镜、电子能谱仪、X射线衍射等研究了在N2气氛中1150℃×10 h等温热处理的Si3N4/Ni,Si3N4/Ni3Al平面偶界面固相反应区的形貌、成分分布、显微结构及相组成。结果表明:Si3N4/Ni界面固相反应形成约20μm厚的反应区,反应区主要由Ni3Si构成,其中分布着大量细密的孔洞;而Si3N4/Ni3Al界面固相反应形成约2μm厚的反应区,反应区具有比Ni3Al高得多的Al含量,反应区由NiAl及Ni3Si构成。Si3N4/Ni3Al具有比Si3N4/Ni高得多的界面化学相容性。

Interfacial solid state reactions of Si_3N_4/Ni and Si_3N_4/Ni_3Al couples

The morphologies,phases,microstructure and elemental distributions of the Si_3N_4/Ni,Si_3N_4/Ni_3Al couples reaction zones annealed at 115℃ for 10 h under N_2 atmosphere were studied by means of scanning electron microscope with energy disperse spectroscopy analyzer and X-ray diffraction. The results show that interfacial solid state reaction of Si_3N_4/Ni forms a reaction zone about 20 μm thickness. The reaction zone is composed of Ni_3Si,in which a lot of small pores are distributed. Comparatively,the interfacial solid state reaction of Si_3N_4/Ni_3Al forms a reaction zone about 2μm thickness. The reaction zone is composed of NiAl and Ni_3Si,containing a very higher Al content than Ni3Al. The Si_3N_4/Ni_3Al couple has much higher chemical compatibility than the Si_3N_4/Ni couple.