中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
Vol. 17 Special 1 November 2007 |
mechanism of electrodeposited nickel coating
(Key Laboratory of Low Dimensional Materials & Application Technology, Ministry of Education,
Faculty of Materials Optoelectronics & Physics, Xiangtan University, Xiangtan 411105, China)
Abstract:Nickel coating deposits with better ductility on a lower carbon steel sheet were produced by electrodeposition method and the electrodeposited nickel coating was deformed with the strain of 10%. Then the surface morphology, the deformation texture and the mechanical properties were analyzed by scanning electron microscopy (SEM), X-ray diffractometry (XRD) and nano-indentation measurement, respectively. The principle of nano-indentation to measure the hardness and elastic modulus of nickel coating was introduced. The relation curves of the load and displacement were obtained, including the original electrodeposited samples and the samples under tension. The results show that: 1) there are only two main texture components Ni (111) and Ni (200) in the nickel coating, and no new texture component is found due to the elongation; 2) after tensile deformation in the coating, the surface roughness increases and the microcrack is found; 3) The hardness and the elastic modulus decrease after tensile deformation; and 4) for the original electrodeposited sample, the indentation depths change with the load, the hardness and the elastic modulus decrease with the increase of the depth. In addition, the investigation of creep shows that the value of creep increases when the tensile strain ε>10%.
Key words: electrodeposited nickel coating; tension deformation; nano-indentation; creep