Method for measuring tail shrinkage length of aluminum alloy plate and application of method

The invention discloses a method for measuring the tail shrinkage length of an aluminum alloy plate and application of the method, and relates to the technical field of aluminum alloy extrusion detection. Wherein the aluminum alloy plate is obtained by extruding an aluminum alloy casting rod through a forward extrusion process, during extrusion, the aluminum alloy casting rod sequentially flows through an extrusion cylinder and an extrusion die, extrusion is stopped at the final stage of extrusion, and extrusion residue is reserved in the extrusion cylinder; the measuring method comprises the following steps: respectively measuring or acquiring the section length and the section width of the aluminum alloy plate, the length of the aluminum alloy casting rod, the barrel diameter of the extrusion barrel, the rod diameter of the aluminum alloy casting rod and the thickness of the extrusion residue; and then the tail shrinkage length is calculated. Based on the measuring method, a large amount of tail shrinkage l