Hot Deformation Behavior and Microstructure Evolution of Cu-Ni-Co-Si Alloys

Materials (Basel). 2020 Apr 27;13(9):2042. doi: 10.3390/ma13092042.

Abstract

The Cu-1.7Ni-1.4Co-0.65Si (wt%) alloy is hot compressed by a Gleeble-1500D machine under a temperature range of 760 to 970 °C and a strain rate range of 0.01 to 10 s-1. The flow stress increases with the extension of strain rate and decreases with the rising of deformation temperature. The dynamic recrystallization behavior happens during the hot compression deformation process. The hot deformation activation energy of the alloy can be calculated as 468.5 kJ/mol, and the high temperature deformation constitutive equation is confirmed. The hot processing map of the alloy is established on the basis of hot deformation behavior and hot working characteristics. With the optimal thermal deformation conditions of 940 to 970 °C and 0.01 to 10 s-1, the fine equiaxed grain and no holes are found in the matrix, which can provide significant guidance for hot deformation processing technology of Cu-Ni-Co-Si alloy.

Keywords: Cu–Ni–Co–Si alloy; constitutive equation; dynamic recrystallization; hot compression deformation; microstructure.