Structure and properties of ductile CuAlMn shape memory alloy synthesized by mechanical alloying and powder metallurgy

Highlights: • A ductile Cu–Al–Mn–Ti–B shape memory alloy with fine grain has been prepared via mechanical alloying and powder metallurgy. • Cu diffraction pattern appeares only after 25 h milling. • The quenched alloy with a single β phase has good ductile and high strength. • The aged alloy with a M18R martensite structure remains a shape memory recovery of 92% after 120 cycles. - Abstract: A ductile Cu–Al–Mn–Ti–B shape memory alloy with high fatigue strength has been prepared via mechanical alloying and powder metallurgy. With increasing milling time, the size of the crystallite grains decreases. Cu diffraction pattern appeared only after milling at a speed of 300 rpm for 25 h. The single phase CuAlMnTiB solid solution powder after 35 h milling was hot-pressed and extruded to form the final alloy. The quenched alloy had a single β phase at room temperature and its yield strength, maximum strength and strain were measured to be 390 MPa, 1015 MPa and 14.4%, respectively. The aged alloy showed a martensite structure at room temperature and had a shape memory recovery of 92% after 120 cycles