Gradient structure wear-resistant composite material and its preparation method

A preparation method of gradient structure wear-resistant composite material, which includes the following steps:

• Step S1:
• Mix coarse-grained wear-resistant material particles and fine-grained wear-resistant material powder uniformly in a volume ratio of 1:100 to 10:1, perform vacuum evaporate on the mixture, and obtain surface modified coarse-grained wear-resistant material particles;
• the coarse-grained wear-resistant material particles are one type of hard alloy particles or a mixture of multiple kinds of hard alloy particles, and the particle size range D50 of the coarse-grained wear-resistant material particles is 1-200mm;
• the fine-grained wear-resistant material powder is iron alloy powder or manganese steel alloy powder, and the particle size range D50 of the fine-grained wear-resistant material powder is 0.1-200 μm;
• Step S2:
• Mix the surface modified coarse-grained wear-resistant material particles, the remaining fine-grained wear-resistant material powder left after Step S1, and a solvent containing a dispersant evenly to obtain a composite slurry;
• Step S3:
• Pour the composite slurry into a mold, vibrate the mold, and after the vibration is completed, heat it to remove the solvent in the composite slurry, wherein the conditions for the vibration are:
• vibration frequency:
• 10 Hz to 5000 Hz, acceleration:
• 1 m/s2 to 1000 m/s2, duration:
• 0.001 h to 10 h;
• Step S4:
• apply pressure on the mold and sinter the mold to obtain gradient structured wear-resistant composite materials.