利用新型的摩擦电喷镀系统在45钢基体上制备 nano-Al2 O3/Ni 复合镀层.运用 SEM、XRD、EDS、TEM等分析方法对复合镀层的表面形貌、微观结构和组织成分进行表征及分析；并分别利用显微硬度计和摩擦磨损试验机对复合镀层的力学性能和摩擦磨损性能进行表征.实验结果表明,nano-Al2 O3/Ni 复合镀层表面平整均匀,晶粒细小,XRD主峰的晶面指数为(111)和(200),平均晶粒大小为20．8 nm,复合镀层截面组织致密,与基质镍结合紧密,EDS结果显示出复合镀层在共沉积过程中,只有极少部分镍发生氧化.由于摩擦,喷射和纳米颗粒的协同作用,复合镀层产生了硬质颗粒弥散强化,细晶强化和高密度位错强化,导致截面平均硬度达676 Hv；油润滑条件下,复合镀层的主要磨损机制为粘着磨损并伴有微切削.
Nano-Al2 O3/Ni composite coatings were prepared on 45 steel substrate by using a novel friction spray electroplating system.The surface morphology,microstructure and composition were analyzed by SEM,XRD, EDS and TEM.The mechanical and tribological properties of the composite coatings were also respectively ana-lyzed by HV-1 000 microharness tester and MM200 wear testing machine.The experimental results showed that nano-Al2 O3/Ni composite coatings possess smoother,finer and more uniform microstructure.The main peaks (111),(200)were demonstrated by the XRD pattern and average grain size of 20.8 nm was calculated.The cross-section morphology of composite coating exhibited denser microstructure and coating was combined tight-ly with matrix metal nickel.The results of EDS analysis showed that little nickel is oxidized during the co-de-posite process.Due to synergism among friction, spraying and nanoparticles, the composite coating was strengthened by the hard-particles-dispersion intensification,fine-crystal intensification intensification and high density dislocation intensification,and average hardness 676 Hv was obtained.The main wear mechanism of composite coatings was adhesive wear and slight cutting under oil lubrication condition.
参考文献
| [1] | Stoudt M.R.;Cammarata R.C..SUPPRESSION OF FATIGUE CRACKING WITH NANOMETER-SCALE MULTILAYERED COATINGS[J].Scripta materialia,20006(6):491-496. |
| [2] | P.S.Song;B.C.Sheu;H.H.Chou.Deposition of plating metals to improve crack growth life[J].International Journal of Fatigue,20013(3):259-270. |
| [3] | R. Montanari;A. Sili;G. Costanza.Improvement of the fatigue behaviour of Al 6061 /20 percent SiC_p composites by means of titanium coatings[J].Composites science and technology,200114(14):2047-2054. |
| [4] | 丁红珍;李尚周.摩擦电刷镀Ni-W-D合金镀液改良及镀层性能研究[J].电镀与涂饰,2005(8):8-10. |
| [5] | 梁志杰;谢凤宽.摩擦电喷镀技术[J].电镀与精饰,1999(5):16-19. |
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