The Effect of Adding Nanodiamond Particles and Heat Treatment on Hardness and Wear Resistance of Ni-P-Nanodiamond Electroless Nanocomposite Coatings

Ni-P electroless composite coatings are produced by hard or soft particles in Ni-P matrices. In the co-deposition particles, nanodiamonds have a very high hardness, biological compatibility, high chemical stability and good resistance to abrasive and harsh environments,. In this study Ni–P nanodiamond composite coatings were deposited in various nanodiamond concentration on steel substrates. The effect of adding nanodiamonds and heat treatment on morphology, crystalline structure, hardness and wear resistance were investigated by FESEM, XRD, micro Vickers and pin on disk. The results demonstrated that coating produced with 0.6 g/l nanodiamond concentration had highest particles incorporation and hardness. The crystalline structure composite coating was finer and surface morphology changed. Also the heat treated composite coating had the highest wear resistance at 4000C for an hr. The mechanisms of improvement of the tribological properties of the electroless composite coating are also discussed.