Guiding principles for creating new high strength-high conductivity copper alloys

Abstract

Solid solution strengthened alloys such as brass and bronze have been widely used as contact materials for energisation in a range of devices due to the fact that they are relatively low cost. In more recent times precipitation strengthened alloys such as copper-beryllium, copper-titanium and copper-nickel-silicon are used due to their excellent strength and conductivity. Yet, little headway has been made in the development of precipitation hardening copper alloys due to the difficulty associated with departing from existing alloy designs and structure control methods. One team of researchers is exploring the use of over-aged material instead of the conventional peak-aged material. This is because previous studies have suggested that wires of this type may have improved strength and conductivity. But there remain many unknowns. Associate Professor Satoshi Semboshi is a researcher based at the Institute for Materials Research, Tohoku University, Japan, who is seeking to shed light on these unknowns.