Combined processing method for preparing anti-corrosion AZ91D magnesium alloy with obdurability

The invention discloses a combined processing method for preparing an anti-corrosion AZ91D magnesium alloy with obdurability. The combined processing method comprises the following steps: step 1, continuous ECAP (Equal Channel Angular Pressing), wherein the step 1 specifically comprises the substeps of: cutting a casting state AZ91D magnesium alloy blocky material into columnar test pieces, uniformly coating a solid lubricant on the surfaces of the test pieces after a regular pre-treatment and on a surface of a mould, putting the test pieces into the mould to be heated to 230 DEG C to 300 DEG C along with the furnace for heat preservation, then continuously performing ECAP deformation for multiple times, and rotating the test pieces for 180 DEG between two adjacent pressing passes to realize ultrafine processing of the alloy tissues; step 2, subsequent micro-arc oxidation surface treatment, wherein the step 2 specifically comprises the substeps of: cutting the test pieces obtained in the step 1 to obtain a shape needed by a member, performing the micro-arc oxidization treatment after grinding, polishing and ultrasonically cleaning the surfaces of the test pieces, putting the test pieces into silicate electrolyte, performing the micro-arc oxidization treatment for 15-20 min under the conditions that an externally applied voltage is 350-400 V, a duty ratio is 15-30% and a frequency of 400-600 Hz to finally obtain the anti-corrosion AZ91D magnesium alloy blocky material with excellent obdurability and corrosion resistance. The combined processing method for preparing the anti-corrosion AZ91D magnesium alloy with obdurability, disclosed by the invention, has the advantages of high yield, simple technological operation as well as equipment requirements and good industrial application prospect.