Study on Electric Field Structure of Micro-Arc Oxidation Process for TC4 Alloy

In order to improve the theory of preparation process of micro-arc oxidation( MAO) film,it 's needed to proceed with in-depth study on the energy conversion process. Film samples which containing titanium oxide and biphasic calcium phosphate ingredients were prepared under different conditions of constant voltage mode and constant current mode,by using micro-arc oxidation power supply. Film surface and cross section morphology and structural characteristics were observed by scanning electron microscopy( SEM),voltage drop status of each unit of the micro-arc oxidation system and characteristics of the thermal cooling system were researched from perspectives of thermal energy and kinetic energy. Results showed that under the constant current mode,power supply voltage and film pressure drop would rise with the increasing of duty ratio,while the hydraulic pressure drop kept constant. The composition of power supply consumption was obtained; the energy conversion process and potential distribution within the range of film were characterized; the energy conversion process of micro-arc discharging was revealed. This study has a quantitative meaning to theoretical study of the process.