Microstructure and properties of a novel ultra-high strength, high elasticity and high plasticity Cu-20Ni-20Mn-0.3Nb-0.3Cr-0.1Zr alloy

摘要

The elongation of high-strength copper alloy with tensile strength over 1300 MPa is generally less than 3%. In this paper, a novel Cu-20Ni-20Mn-0.3Nb-0.3Cr-0.1Zr (wt.%) alloy with high strength, high elasticity and high plasticity was prepared. Its tensile strength, elastic modulus and elongation is 1445 MPa, 147 GPa and 6.8%, respectively. On the basis of Cu-20Ni-20Mn alloy, microalloying Nb, Cr, Zr elements were added to restrain discontinuous precipitation and improve the properties of the alloys. By matching reasonable heat treatment process, a fine and highly uniform grain structure was obtained, which is the main reason for the increase of elongation. TEM and 3DAP results suggested that a large number of nanoscale NiMn precipitates are the main source of high strength in the alloy. The designed alloy has excellent comprehensive properties, which can be used for the preparation of precision sensing parts, elastic components. (C) 2020 Elsevier B.V. All rights reserved.