A Study of the Pore Surface State of Porous TiNi-based Materials Obtained by SHS at Various Ignition Temperatures
Structural features of porous TiNi-based materials obtained by SHS at temperatures of synthesis beginning of400 Cand600 Chave been investigated. It is found that finely porous material with a porosity P=75 % was obtained at the temperature of400 C. A surface of pore walls contains a dendritic relief, oxycarbidenitride layer and a multitude of secondary phase particles. Phase and chemical composition of the material is non-uniform. SHS material obtained at the synthesis beginning temperature of600 °Cis characterized as a coarse-porosity one P=65 %. Nano- and micropores are practically absent. The oxycarbidenitride surface layer with a variable thickness is substantially free of secondary inclusions due to the more complete processes of alloy formation. This layer has an own substructure based on carbonitride and oxynitride layers.