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The micro-arc oxidation process of 6N01 alumin m alloy under different control modes of the electrolyte temperature has been discussed in detail. Compared to the thermostatically controlled treatment, the process has different discharge characteristics when treated without control of electrolyte temperature, particularly at the later stage of the treatment. To investigate the discharge mechanism, scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), energy dispersive spectrometry (EDS) and X-ray diffractometry (XRD) were used to characterize the morphology and elemental composition of the films. Mott-Schottky (M-S) and electrochemical impendence spectroscopy (EIS) measurements were also used to reveal the correlation between the discharge mechanism and electronic property and the interface model during the film formation at the later stage. The results indicate that the galvanostatic MAO treatment of 6N01 alumin m alloy consists of three main stages under both control modes of the electrolyte temperature. The length of the second anodization stage is prolonged because of the increased electrolyte temperature, and the discharge mechanism changes into the enhanced anodizing process instead of the intensive micro-arc oxidation regime in the boiling electrolyte at the final stage when the micro-arc oxidation treatment is performed without control of electrolyte temperature. Meanwhile, the treatment without control of electrolyte temperature ultimately leads to a thicker and rougher film with a respectably thick inner barrier film and a lower content of γ-Al2O3. Further, in the anodizing electrolyte, the sample that is coated with an n-type semiconducting film has a thicker space charge, a more positive flat band potential and a smaller donor density when it is treated without control of electrolyte temperature for 30 min. Accordingly, the charge transition occurs with more difficulty. Apart from that, a high resistance of the barrier layer is found to restrict the transformation of cations and anions. Thus, the conversion of the discharge mechanism is proven to promote the growth of MAO films based on the electronic properties and interface model analysis when the MAO treatment is carried out without control of electrolyte temperature.