Igor Vrublevsky

Stored Charge and its Influence on Properties of Anodic Alumina Films

In porous and barrier-type anodic alumina films, the stored charge has electronic nature and it plays a significant role in the process of aluminum anodizing. The charge stored can modify the distribution of local field generated by a voltage applied and thus it can affect the oxide growth. The method for the investigation of thermally activated defects in anodic alumina films by reanodizing technique was also described. It was applied for computation of activation energy of electron traps in barrier layer for sulfuric and oxalic acid alumina films and concentration of the traps.

Investigation of the efficiency of the heat dissipation for the heat-conducting circuit boards made of aluminum with the nanoporous alumina layer

The results of the investigation of the efficiency of the heat dissipation from the circuit board made of aluminum with the nanoporous alumina layer and conducting copper layer. In the construction of these circuit boards nanoporous alumina was used as insulator, which provided heat transfer from topology elements to the aluminum substrate. The conducting copper layer was formed by electroplating followed by chemical deposition of thin nickel layer. The diode MBRB16H60 was used as an element possessing high level of heat release. The temperature on the surface of the circuit board was measured by the thermocouple and the infrared images of the samples were studied by the thermal imaging camera. It was shown that proposed circuit boards allow significantly increasing the efficiency of the heat dissipation from the circuit board elements and reducing their operating temperature. The thermal conductivity of the nanoporous anodic alumina layer was determined to be 1.56 W K−1 m−1.

Study of thermal conductivity of nanoporous anodic alumina layer formed in sulphuric acid using steady-state heat flow technique

The paper presents the results of studies of thermal characteristics of nanoporous anodic alumina layer formed in sulphuric acid. One-sided heating of aluminum boards by heating element from carbon filament was used. The temperature of the back side of the board was kept constant by using an aluminum heatsink. Thermograms of aluminum board surface were taken by thermal imaging camera MobIR M4.