Abstract
Pulse plating was used to prepare nickel films from a Watts bath with no additives. The influences of the current pulse electrolysis parameters of duty ratio=0.03-0.33, Ton=0.1-5 ms, and Iav=2-10Adm-2, on the hardness, texture, and crystal orientation were investigated. Those characteristics were studied respectively using a nano-indenter hardness tester, scanning electron microscopy, and XRD. Results showed the importance of Iav for obtaining high-hardness films. The highest value of hardness was 4.5 GPa at Ton=1 ms, duty ratio=0.1, and Iav=10 Adm-2. Hardness is related closely to the texture. A Hall-Petch relation was observed between the hardness and grain size. The preferred orientation changed to the(311)→(220)→(200)plane with increase of the duty ratio when the pulse parameters were Ton=1 ms and Iav=5Adm-2.
