Effects of the grain size, boundary type and texture on the bending properties of phosphorus bronze strips

Abstract

The bending formability of phosphorus bronze strips plays a critical role in determining the service performance of board-to-board connectors. The mechanisms of grain size, boundary type, and texture influences on bending property of phosphorus bronze was systematically investigated in this work. The results demonstrate that the bending properties of phosphorus bronze strips was improved with reduced grain size, and excellent bending formability can be achieved when the grain size was controlled below 2 μm. Grain boundary engineering, which increases the fraction of special boundaries, effectively mitigates internal stress concentration within grains, thereby improving the bending properties of phosphorus bronze strips. However, as rolling reduction increases, deformation textures such as Brass, Goss, and rotated-Goss significantly strengthen. Notably, the continuous evolution of the Brass texture can induce shear band formation in the alloy, which adversely affects the bending properties along the bad way. Synergistic control of fine grain, boundary type, and cold deformation is essential for achieving high tensile strength and superior bending formability of phosphorus bronze strips. This research offers valuable insights into the development of advanced connector materials