Particle-assisted texture engineering for achieving exceptional bendability of Cu–Ni–Si alloy

Abstract

This study presents a novel processing strategy that enables unprecedented bendability in a high-strength Cu–Ni–Si alloy containing 4.5 wt% Ni—achieving a bend radius-to-thickness ratio of 0.25 without cracking, which significantly exceeds previously reported performance. The key approach lies in particle-assisted texture engineering, achieved through intermediate annealing (IA). Texture analysis reveals that IA promotes the formation of cube ({001}) texture within particle-affected deformation zones (PADZs) surrounding dispersed Ni2Si particles, thereby triggering localized recrystallization. The cube texture fraction increases markedly to 14 % in the IA-treated alloy, compared to only 2 % in the untreated counterpart. Despite comparable mechanical and electrical properties between the two alloys, the IA-treated alloy exhibits markedly superior bendability. This improvement is attributed to the suppression of shear banding, enabled by the increased cube texture. Crystal plasticity finite element modeling elucidates the mechanistic link between PADZs and texture evolution, offering quantitative insight into the microstructural origins of bendability. These findings demonstrate that IA and particle dispersion are effective strategies for tailoring crystallographic textures to achieve exceptional bendability in high-strength Cu alloys. This work offers a pathway for designing high-performance Cu alloys suitable for next-generation electronic components.