Fabricação e caracterização térmica de liga com memória de forma CU-AL-HF

Abstract

In this work, the thermal properties of the alloy Cu-13%Al-0.5% Hf (percentage by weight), capable of forming memory, were carried out. The alloy was fabricated by the Plasma Skul Push-Pull (PSPP) technique, whose procedure consists of injecting the metal into a metal mold after a casting process by a rotating plasma torch. Via Differential Scanning Calorimetry (DSC), the existence of the reversible martensitic transformation in the material and the instability of its functional properties were verified by thermal cycling process. The results showed high phase change temperatures (MS>200°C) in addition to a high thermal degradation of the system, with well defined phase transformation peaks in only six analyzes, of the seven that were submitted. In this sense, even though the insertion of the Hafnium (Hf) in the Cu-Al matrix has validated the reach of high transformation temperatures, the functional properties were still unsatisfactory for the effective targeting of the LMF for applications involving HTSMAs.