纳米α-Al_2O_3颗粒弥散强化镍基复合涂层的耐磨性能研究

Abrasive Resistance of Nanometer α-Al_2O_3 Particle Dispersion Reinforced Ni Matrix Composite Coating

将纳米α-A l2O3颗粒或N i包裹的纳米α-A l2O3复合粉和镍基粉用湿法混合,采用火焰热喷涂工艺制备了复合涂层,用磨粒磨损试验机进行磨损试验,研究了纳米α-A l2O3的体积分数、粒径和是否预先进行包裹处理对涂层喷焊性和耐磨粒磨损性能的影响。结果表明,纳米α-A l2O3以包裹形式加入能有效改善弥散相与N i基涂层的相容性,相应涂层的耐磨性优于未包裹处理;当纳米A l2O3的体积分数为2%时,涂层的耐磨性能最好,为N i基涂层的2倍多;在相同的体积分数下,随着涂层中弥散强化相尺寸的减小,涂层的耐磨性提高。

The nanometer α-Al2O3-metal composite coating was prepared by flash thermal spray method and it was abraded on abrasive wear machine to study its abrasive resistance property. The effect of the volume fraction, the size and the coated status of the nanometer α-Al2O3 on the abrasive wear property of the coating were studied. The result shows that the abrasive wear resistance property of the coating strengthened by the coated nanometer α-Al2O3 is better than that by the uncoated powder. The coated nanometer α-Al2O3 improves the wetting property of the nanometer α-Al2O3 in the Ni-based coating and improves the abrasive resistance of the coating. With 2% volume fraction addition of nanometer α-Al2O3 ,the coating has the best abrasive wear resistance property and is twice of the pure Ni-based powder coating. With the same additive volume, the abrasive resistance of the coating increases as the size of the dispersion strengthening phase decreases.