The invention discloses a sealing agent for aluminum and aluminum
alloy anode oxide films and a preparation method for the sealing agent. The sealing agent comprises the following raw materials by lL: 15-20g of
lanthanide nitrate, 0.6-0.8g of
oxidizing agent, 0.25-0.3g of stabilizing agent and deionized water, wherein the additive amount of the deionized water is the amount of adding the deionized water until the volume is constant at 1L after the rest raw materials are mixed. According to the sealing agent disclosed by the invention, by utilizing the combined action of rare-earth
metal and the
oxidizing agent, porous
layers of the
anode oxide films can be effectively sealed, and the
corrosion resistance of the
anode oxide films is obviously improved. Meanwhile, the sealing agent disclosed by the invention does not contain
chromium,
nickel or
fluorine, therefore, the
human body cannot be harmed, and the environment cannot be polluted. The sealing agent is a green environmental-protection sealing agent. Moreover, the aluminum and aluminum
alloy anode oxide films can be sealed at normal temperature, therefore, not only is the
energy consumption reduced but also the operation convenient is improved. After being treated by the sealing agent disclosed by the invention, the aluminum and aluminum
alloy anode oxide films are compact in
surface structure, is in uniform golden yellow and is higher in
bonding strength.