(a) From the plot of yield strength versus (grain diameter)–1/2 for a 70 Cu–30 Zn cartridg...

(a) From the plot of yield strength versus (grain diameter)–1/2 for a 70 Cu–30 Zn cartridge brass in Figure 7.15, determine values for the constants σ0 and ky in Equation 7.7.

(b) Now predict the yield strength of this alloy when the average grain diameter is 2.0 × 10–3 mm.

Figure 7.15 The influence of grain size on the yield strength of a 70 Cu–30 Zn brass alloy. Note that the grain diameter increases from right to left and is not linear. (Adapted from H. Suzuki, “The Relation between the Structure and Mechanical Properties of Metals,” Vol. II, National Physical Laboratory, Symposium No. 15, 1963, p.)

 (7.7)