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Composite gradient plates with GCr15, Q420 and IF steel was fabricated by vacuumrolling composite (VRC) technology and the forage harvester blades were prepared. Microstructure, chemical composition and hardness distribution, and shear strength in the interface of composite gradient plates were inspected. In order to compare the cutting performance between composite gradient material selfsharpening blades and commercial blades, the field experiment was carried out. The results indicated that a more disordered metallurgical bonding characteristics because of materials interbiting characteristics at the interface of different plates (GCr15/Q420, Q420/IF) during rolling process was formed. With fewer microstructure defects, transition zone was formed due to the chemical compositions diffusion in the interface. The shear strength of the bonding interface exceeded the requirements of the national standard, which can meet the requirements of gradient material selfsharpening blades. The interface fracture mode was ductile fracture with good plasticity. There was a relatively gentle hardness gradient variation between different interfaces. The flank surface, point tip and cutting edge of selfsharpening blades were made up of GCr15 steel with higher hardness and wear resistance. Hardness gradient variation and uniform wearing for rake surface of selfsharpening blades were remarkably exhibited. In the operation process, selfsharpening blades improved the operation efficiency and service life. It can keep the tool tip in the prominent position and edge curvature radius slightly change, which can maintain sharpness property of blades and lowdamage cutting of regeneration. Field experiment can obtain the results comparison of wear weightloss rate and macroscopic morphology between the composite gradient material selfsharpening blades and commercial blades. The results showed that under the same operation conditions, compared with commercial blades, the gradient material selfsharpening blades had more excellent properties: slightly variation of arc radius, edge curvature radius, and abrasive resistance. The further field experiment results indicated that the wear resistance of the selfsharpening blades was more than three times of that of commercial blades. 