Mechanics behaviors and electrical conductivity of beryllium bronze alloy entangled metallic wire material: Experimental study and theoretical modeling

Abstract

In the present work, a novel entangled metallic wire material (EMWM) with good mechanical properties and electrical conductivity was developed by using beryllium bronze alloy wire as raw material. A series of thermal-mechanical-electrical coupling tests were carried out to investigate the mechanical properties (average stiffness, loss factor) and electrical conductivity of beryllium bronze alloy entangled metallic wire material (QBe2-EMWM) and austenitic stainless steel entangled metallic wire material (304-EMWM). The effect of the density and ambient temperature on mechanical performances and resistance properties of EMWM were analyzed in detail. It is found that the mechanical properties of QBe2-EMWM are similar to those of austenitic stainless steel entangled metallic wire material (304-EMWM). The electrical resistance of EMWM decreases with the increase of density. Moreover, the electrical resistance of QBe2-EMWM is significantly lower than 304-EMWM and is only 5 % of 304-EMWM. In the aspect of theoretical modeling, based on a cube unit-cell approach, a simplified electrical resistor network was derived from modeling low-frequency current flow through the EMWM. Considering the influence of ambient temperature, the simplified resistor network model was modified by referring to the temperature term of the Johnson-Cook model, and then the conductivity model considering temperature effect for EMWM was established. The accuracy of the theoretical electrical model of EMWM was verified by comparing the calculated results with the experimental data. The results show that the proposed model can adequately predict the electrical conductivity characteristics of EMWM under different temperatures.