Piezoelectric energy harvester converting strain energy into kinetic energy for extremely low frequency operation Appl. Phys. Lett.

Electroforming has been applied in the fabrication of a mold. However, its lower microhardness has prevented its wider usage in general plastics and optical mold making. In this paper, CeO 2 nanoparticles is first added to the bath to improve the microhardness of the electroformed microprism mold. Compared with microprism pure nickel mold, the microhardness and the wear resistance of the microprism Ni-CeO 2 nanocomposite mold were significantly improved. The maximum microhardness of 530 HV was observed in the nanocomposite deposits obtained at the current density of 1 Adm -2 , and the microhardness of pure nickel is approximately 291 HV. Finally, a microprism Ni-CeO 2 nanocomposite mold was successfully electroformed.

The improvement of the incorporated nanoparticle content in nanocomposite coatings is a key factor in composite electrodeposition. This paper describes a modified sediment co-deposition (SCD) technique which has been developed to produce Ni-CeO 2 nanocomposite coatings, with the aim of enhancing the embedded CeO 2 nanoparticle content. The maximum content of CeO 2 particles in the nanocomposite coatings created using this modified SCD technique is 7?09 wt-%, which is the highest reported. A maximum microhardness of 630 HV is obtained, which is significantly greater than that observed in nanocomposite coatings fabricated using the conventional electrodeposition technique. As the wear resistance of the nanocomposite coatings increases with increasing incorporated CeO 2 nanoparticle content, so this nanocomposite coating with an incorporated CeO 2 nanoparticle content of 7?09 wt-% exhibits maximum wear resistance.

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The ferrite plays an important role in key component materials for nuclear power plant. The study was performed on ferritic alloys with various Cr content ranging from 10 to 38wt%. The Vickers-hardness and mechanical test results indicate that the high Cr content will cause a hardening and strengthening effect on the ferrite steel. Meanwhile, it can be concluded that the ferritic alloy suffers a reduction of toughness and a failure mode transition from ductile to brittle fracture with the increasing Cr content from the SEM fractography analysis.