Mechanical properties and deformation behaviour of laminated titanium-intermetallic composites synthesised using Ti and Cu foils

Abstract

Ti-intermetallic laminated composites were fabricated via reaction synthesis in vacuum using foils of titanium and copper with controlled temperature, treating time and pressure. Microstructural examinations using SEM and EDX demonstrated that copper layers were completely consumed and five intermetallic compounds: Ti2CU, TiCu (predominant phase), Ti 3CU4, Ti2Cu3 and TiCu4 were formed. The mechanical properties and fracture behaviour of the fabricated composites were examined. The results showed that treating time at 900°C was a main factor determining properties. After 5 hours of treating all investigated composites with the same thickness of starting Ti foil have higher yield strength, higher ultimate tensile strength and higher flexural strength than composites after 0.5 hour of treating. Only strain at fracture of the composites decreases with increasing of the treating time. The composites exhibited good cohesion between layers during tensile test. Delamination of layers occurred during three-point bending test, especially when the load perpendicular to the laminates was applied.