## Materials Science and Engineering: An Introduction

σ = 6.67 x $10^{6}$ $(Ω-m)^{-1}$ (Answers may slightly vary.)
Given: Tensile strength of Cu-Ni = 275 MPa (40,000psi) Required: Electrical conductivity of Cu-Ni Solution: From Figure 7.16a, the composition of an alloy having 275 MPa is about 10 wt% Ni. From Figure 18.9, the resistivity of this composition is about 15 x $10^{-8}$ Ω-m As conductivity is the reciprocal of resistivity (Equation 18.4), σ = $\frac{1}{p}$ = $\frac{1}{15 \times10^{-8} Ω-m}$ σ = 6.67 x $10^{6}$ $(Ω-m)^{-1}$