Solution We are asked to compute the diffusion coefficients of C in both and iron at 900C. Using the data in   Table 6.2, = 1.69 10-10 m2/s = 5.86 10-12 m2/s The for diffusion of C in BCC  iron is larger, the reason being that the atomic packing factor is smaller D than for FCC iron (0.68 versus 0.74—Section 3.4); this means that there is slightly more interstitial void space in  the BCC Fe, and, therefore, the motion of the interstitial carbon atoms occurs more easily. 6.17 Using the data in Table 6.2, compute the value of D for the diffusion of zinc in copper at 650ºC. Solution Incorporating the appropriate data from Table 6.2 into Equation 6.8 leads to = 4.8 10-16 m2/s
Solution We are asked to compute the diffusion coefficients of C in both  and  iron at 900C. Using the data in Table 6.2, = 1.69 10-10 m2/s = 5.86 10-12 m2/s The D for diffusion of C in BCC  iron is larger, the reason being that the atomic packing factor is smaller than for FCC  iron (0.68 versus 0.74—Section 3.4); this means that there is slightly more interstitial void space in the BCC Fe, and, therefore, the motion of the interstitial carbon atoms occurs more easily. 6.17 Using the data in Table 6.2, compute the value of D for the diffusion of zinc in copper at 650ºC. Solution Incorporating the appropriate data from Table 6.2 into Equation 6.8 leads to = 4.8 10-16 m2/s
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