Influence of Bath Additives on the Thermal Stability of the Nanostructure and Hardness of Ni Films Processed by Electrodeposition

Coatings

Tamás Kolonits¹  Jeno Gubicza¹  Zsolt Czigány²  László Péter³  Imre Bakonyi³ 

[1] Department of Material Physics, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, H-1117 Budapest, Hungary;Institute for Technical Physics and Materials Science, Centre for Energy Research, Hungarian Academy of Sciences, Konkoly-Thege M. út 29-33, H-1121 Budapest, Hungary;Wigner Research Centre for Physics, Hungarian Academy of Sciences, Konkoly-Thege út 29-33, H-1121 Budapest, Hungary;

关键词: nickel film;    electrodeposition;    annealing;    microstructure;    hardness;   

DOI  :  10.3390/coatings9100644

来源: DOAJ

【 摘 要 】

The effect of bath additives on the thermal stability of the microstructure and hardness of nanocrystalline Ni foils processed by electrodeposition was studied. Three samples with a thickness of 20 μm were prepared: one without any additive and two others with saccharin or trisodium citrate additives. Then, the specimens were heat-treated at different temperatures up to 1000 K. It was found that for the additive-free sample the recovery of the microstructure and the reduction of the hardness started only at temperatures higher than 500 K. At the same time, a decrease of the defect density and hardness was observed even at 400 K for the additive-containing films. This was explained by the higher defect density, which increased the thermodynamic driving force for recovery during annealing. At the highest applied temperature (1000 K), this larger thermodynamic driving force resulted in a recrystallization in the sulfur-containing sample, leading to a very low hardness of about 1000 MPa as compared to the additive-free sample (1300 MPa). On the other hand, the sample deposited with trisodium citrate additive showed a better thermal stability at 1000 K than the additive-free sample: the hardness remained as high as 2000 MPa even at 1000 K.

【 授权许可】

Unknown