Experimental study on surface characteristics and thermal conductivity of new zirconium alloy with oxide layer

摘要

The surface properties and thermal conductivity of oxide layer formed on the new zirconium alloy due to high temperature steam oxidation are studied in this paper. The thickness of oxide layer, surface wettability and thermal conductivity are measured. The effects of oxidation temperature and time on the wettability and thermal conductivity of zirconium alloy are analyzed. The results show that zirconium on the surface is fully oxidized to ZrO_2, and the difference of surface wettability is caused by different surface morphology. The characteristics of oxide layer surface cracks will affect the surface wettability. At the same oxidation temperature, with increasing time duration, the size and number of oxide layer cracks increase. The change of thermal conductivity is the result of competition among factors such as the development of recrystallization process, the increase of oxide layer thickness and the influence of pores and cracks.