Atmospheric Heat Dispersion Research of Mg-Al-Zn Magnesium Alloys

The atmospheric heat dispersion of magnesium alloys AZ80, AZ31, ZK60 and aluminum alloys AA6082 were measured in the temperature range of 20 similar to 220 degrees C. The thermal dispersion curves of the columnar model could be exponentially fitted as T=T-0+Delta T-0.exp(-t/A(0)). The result shows that the solution treatment can decrease the thermal conductivity of the magnesium alloys. However, the solution plus aging treatment can increase the thermal conductivity. The relationship between Delta T/T and the heat dispersion rate was also studied. The heat dispersion rate of high columns (60 mm) is about two times larger than that of low columns (20 mm) in the condition of forced air convection, while there is no obvious difference in the condition of natural convection. Moreover, the dispersion properties of these alloys can be evidently divided into two regions by Delta T/T in natural convection. There is no much difference among AZ80, AZ31, AA6082 alloys when 0.05<Delta T/T<0.25 (20 similar to 120 degrees C), while the AZ80 and AZ31 exhibit superior performance to AA6082 alloys when 0.25<Delta T/T<0.45 (120 similar to 220 degrees C).