Composite energy absorption structure based on unit polycrystalline micro-truss structure shaped like Chinese character'mi 'and 3D printing method of composite energy absorption structure

The invention relates to a composite energy absorption structure based on a unit polycrystalline micro-truss structure shaped like a Chinese character'mi 'and a 3D printing method of the composite energy absorption structure. The composite energy absorption structure is composed of a plurality of layers of polycrystalline micro-truss structures which are subjected to 3D printing layer by layer inthe Z-axis direction. The polycrystalline micro-truss structure comprises a plurality of twin-crystal micro-truss areas with the center line of the polycrystalline micro-truss structure as the symmetric line, each twin-crystal micro-truss area is formed by rotating a left single-crystal micro-truss structure body and a right single-crystal micro-truss structure body with the center line of the twin-crystal micro-truss area as the symmetric line around the Z axis in opposite directions at the same angle, and the two-dimensional dot array structure units are *-shaped units. According to the invention, different areas ar