碳涂层对SiC纤维增强钛基复合材料界面显微结构及性能的影响

研究涂碳的SiC(C)/Ti-6Al-4V和无涂碳的SiC/Ti-6Al-4V材料的界面结构以及结合强度。结果表明:碳涂层阻止了径向纤维间的相互作用,该涂层界面反应物只是TiC,这些产物包含邻近碳涂层生成的细小晶粒和邻近金属基体生成的粗大晶粒;在无涂碳界面上,相邻纤维一侧产生的是TiC薄层,毗邻金属基体产生的是TiC和Ti5Si3晶粒组成的厚混合物,晶粒的大小从纤维到基体逐渐增大。涂炭和无涂碳复合材料的界面结合强度分别是(118.2±4.24),(230±6.28)MPa,证明碳涂层在纤维和基体之间提供了一个弱结合界面。涂碳纤维复合材料的界面结合发生在涂碳层和反应层之间,而无涂碳发生在纤维和反应层之间。

Interface microstructure and properties of SiC fiber coated with carbon reinforced titanium matrix composites

Interface microstructure and bonding strength of SiC(C)/Ti-6Al-4V and SiC/Ti-6Al-4V material were compared.Carbon coating prevents radial fiber interactions,and the product of SiC(C)/Ti-6Al-4V interfacial reaction is TiC,the product contains fine crystal grain formed near carbon coating and coarse grain generated near metal matrix.At the interface of SiC/Ti-6Al-4V material,TiC layer is formed at fiber side,thick mixture containing TiC and Ti5Si3 grains is produced near metal matrix.Grain size increases gradually from fiber to substrate interfacial bonding strength of SiC(C)Ti-6Al-4V and SiC/Ti-6Al-4V composites is(11.8+4.24) and(230+6.28) MPa,respectively.Interface bonding of coated carbon fiber composite material occurs in the coated carbon layer and reaction layer,the interfacial combination of uncoated fiber composite is between fiber and reaction layer.