We prepared electroplated nano-ordered multilayered Co/Pd films on an electropolished polycrystalline copper substrate using an automatic plating machine and confirmed that the films show a remanent perpendicular magnetic anisotropy which depends on the Co film thickness. The effect of underlayer films using Pd, Sn, Pt, Rh films between Co/Pd films and the copper substrate was studied. When Sn film was used as the underlayer film, higher magnetic properties than when using other underlayers, i. e., SQR=0.79, coercive force=680 Oe, were obtained.
The antibacterial activity for pathogenic and food-poisoning bacteria and affinity for biomaterial adsorption of electroless Ni-P-PTFE plated composite coating on stainless steel were studied. The antibacterial abilities of electrolytic Ni plated and electroless Ni-P plated coatings on stainless steel for Escherichia coli increased with decreasing their spontaneous electrode potentials, suggesting that the amount of Ni2+ dissolved from the plated coatings was correlated with the magnitude of antibacterial ability. Growth of pathogenic and food-poisoning bacteria, i. e., Escherichia spp. (coli and O157), Staphylococcus spp. (aureus and MRSA), Salmonella spp., Klebsialla spp., and Pseudomonas spp., was inhibited completely after being in contact with electroless Ni-P-PTFE plated coating for 24 h. The Ni-P and Ni-P-PTFE plated coatings showed high affinities for E. coli adhesion and bovine serum albumin (BSA) adsorption compared with those of stainless steel. Kinetic analysis of cleaning curves of BSA-fouled Ni-P and Ni-P-PTFE plated coatings showed that the first-order desorption rate constants for Ni-P and Ni-P-PTFE plated coatings were lower by one order of magnitude than those for stainless steel. These results indicated that Ni-P-PTFE plated coating had a significantly high antibacterial ability, whereas its surface was more susceptible to biofouling than stainless steel.
Activities of the zinc ionic species in the 1-ethyl-3-methylimidazolium bromide (EMIB) -ZnBr2-ethylene glycol (EG) baths were calculated by the computer simulation method fitting the measured and calculated rest potential of Zn, and the relationships between the calculated activities and the results of the actual Zn electrodeposits were considered. Smooth and metallic colored Zn deposits with 100% of cathodic current efficiencies even at high current densities of 200-300 Am−2 were obtained from baths in which the activities of ZnBr42− were dominant compared with those of ZnBr3− and Br−. This suggests that ZnBr42− is the effective Zn ionic species for Zn electrodeposition. At compositions where the activities of ZnBr3− were relatively high, the dendritic deposits were obtained at the edge of the substrate. The reduction of ZnBr3− causes the dendritic deposits. The appropriate amount of EG addition to EMIB-ZnBr2 bath promotes the formation of ZnBr42− that forms the smooth Zn deposits.
A method for fatigue reliability evaluation of Hybrid DLC to ensure safe design is proposed. This concept represents a major contribution to the fatigue reliability design method for surface modification components, namely "The influence of surface modification processing on materials with internal failures." The fatigue reliability of high-speed tool steel SKH-51, coated with Hybrid DLC, is described. Hybrid DLC is a compound film process that produces a DLC film by P-CVD on a PVD system TiN hard film. This material follows the weakest link model. The variation in the inclusion leading to internal destruction was examined statistically. Convergence of the variation produced in the S-N diagram was tried. The influence of coating processing on fatigue fracture mechanism was considered. In particular attention was paid to change due to the heat treatment history of the base material. The industrial significansce of the acquired knowledge was examined.
One dimensionally (1D) ordered structures of nanoparticles were prepared using templates composed of fine trenches of nanometer scale. Spreading a solution of nanoparticles (Fe2O3) of 11 nm diameter on a substrate with fine trenches that were prepared by electron beam lithography, and subsequent evaporation of the solvent yielded a 1D ordered structure of nanoparticles with interval of 45nm.