The application relates to a repair protective layer preparation method of a
slurry circulating pump impeller, which comprises the following steps: a surface pretreatment step, a
laser cladding additive manufacturing step, a finishing step, a surface treatment step and a
corrosion and
wear resistance treatment step, wherein the
laser cladding additive manufacturing step comprises the following steps: automatically planning a
route by using a
laser cladding device, setting a repair
transition layer, and setting at least one repair layer on the repair
transition layer, wherein the scanning speed of the laser cladding device for setting the repair layer is greater than the scanning speed for setting the repair
transition layer, the repair transition layer is made of an iron-based
alloy material matched with the material of the
impeller, and the repair layer is made of an iron-based
alloy material with micro-nano particles added with WC and CeO2. The repair structure formed in this way has high
bonding strength with the
impeller base, and the impeller base and the repair layer are better integrated; the repair layer has the advantages of strength,
toughness,
wear resistance and
corrosion resistance, the impeller as a whole is repaired to meet the use requirements, and the service life is prolonged.