Materials, Methods & Technologies, Volume 8, 2014

Rezumat: Multilayer composites were obtained by diffusion welding under pressure of packets collected from thin foils of niobium or titanium and aluminum. Welding temperature for composites with Nb and Al was up to 1700°C, for composites of Ti and Al does not exceed 1200–1250°C. Layers hardening intermetallic compounds of Nb₃Al and Nb₂Al for Ti₃Al and TiAl were formed by interdiffusion of niobium or titanium with aluminum. Mechanical properties at temperatures up to 1300–1350°C for Nb/Al and to 850–900°C for Ti/Al composites were determined by short-time tests for 3-point bending. Creep tests at these temperatures were also carried out. Experimental data for multilayer Ti/Al-composites showed that when stress σ, equal to 200 MPa, its creep rate at 750°C is ~6·10⁻⁴ h⁻¹. When σ = 50 MPa, it was equal to 10⁻⁴ h⁻¹, which corresponds to 1% deformation of the sample for 100 hours.