The Effects of Cold Rolling and Annealing on the Microstructure Evolution of Ordered C-2000 Alloy during Metallic Wire Preparation

Abstract

When using well-designed multiple-stage heavy-drawn processes, i.e., cold rolling, drawing and cluster drawing to fabricate a metallic wire or fiber in steps, cold rolling and annealing are critical steps due to their effect on the initial microstructure before the heavy-drawn process. Understanding the relationship between microstructure evolution and cold rolling followed by annealing is required for smoothly implementing the heavy-drawn process. In this work, the evolution behavior in terms of the microstructure during cold rolling followed by annealing was investigated in a novel C-2000 alloy that is a promising candidate material for the fabrication of high-performance metallicwire. The investigation encompassed parameters including the grain size, grain boundaries, recrystallization texture, and short-range ordered (SRO) structure. Results show that the grain size distribution of the cold-rolledC-2000 alloy followed by annealing at 900 °C is quite uneven. The low-angle grain boundaries induced by cold rolling are more frequently transformed into the Σ3 twin boundaries during recrystallization. At the initial stage of annealing at 900 °C after cold rolling, the contents of different texture components are significantly different, but the differences tend to decrease with the extension of the annealing time. In addition, cold rolling destroys SRO domains formed during solid solution water quenching, and the destruction of SRO affects the precipitation of the long-range ordered phase during annealing. Incoherent Σ3ic with curved grain boundaries play an important role in the recrystallization of nucleation sites in the process of static recrystallization by nucleation–growth.