kYr, : where increase weight, constant [23]. Figure shows weight increase 350°C, 400°C, 450°C [280]. volume oxide formed is greater volume metal which (Pilling Bedworth ratio 1.26), metal should occur [281]. growth oxide alloys takes place migration metal through the oxide layer reaction oxygen of parabolic oxidation kinetics suggests rate-controlling oxidation of melts diffusion process slag. linear depen-

Chapter

ABSTRACT

Figure 2 The oxidation kinetics in 99.999% lead at 350°C, 4OQ°C and 450°C [280]. (Courtesy of Dr. S. A. Hiscock.)

is lower than in PbO, so that the formation of Pb30 4 leads to a reduction of the rate constant [280,282].