Study of a superelastic Cu-base alloy intended for applications in earthquake engineering

S. MONTECINOS; A. SEPÚLVEDA; M. MORONI; F. LUND

Viña del Mar

Workshop; Frontiers in Materials Research; 2004

Centro Interdisciplinario de Materiales Avanzados CIMAT

A preliminary characterization of the mechanical behaviour of a polycrystalline Cu-11.8wt.%-0.5wt.%Be alloy,    as 3 mm diameter wires, was here presented, having in mind its eventual application in seismic energy dissipation devices based in superelastic materials. Thus, mechanical test were performed at a laboratory temperature of 24ºC and at frequency of 1 Hz for cyclic tensile tests. Microstructure was austenitic and mean grain size was of 0.5 mm. In a tensile test, the material exhibited an ultimate tensile strength of 5,146 kg/cm2 (504 MPa) and a total strain at fracture of 15.1%. Fracture was transgranular.  Hysteresis loops were present in cyclic tensile tests. As strain amplitude was increased, damping capacity B also increased.  The superelastic effect was evident up to strains of 2.3-2.6%, with corresponding values of B= 4.7- 5.0%.  An adiabatic heating of up to about 7 ºC was detected.