Nanosheet Ca2Nb3O20 (ns-CN) layers with pseudo-perovskite-type crystal configuration were applied on the surface of polycrystalline metal substrates to achieve preferential crystal orientation of Pb(Zr,Ti)O3 (PZT) films for the purpose of enhanced ferroelectricity comparable to that of epitaxial thin films. PZT films with tetragonal symmetry (Zr/Ti=0.40:0.60) were fabricated by chemical solution deposition (CSD) on ns-CN-buffered Inconel 625 and SUS 316L substrates, while ns-CN was applied on the the substrates by dip-coating. The preferential crystal growth on the ns-CN layer can be achieved by favorable lattice matching between (001)/(100)PZT and (001)ns-CN planes. The degree of (001) orientation was increased for PZT films on ns-CN/Inconel 625 and ns-CN/SUS 316L substrates, whereas randomly-oriented PZT films with a lower degree of (001) orientation were grown on bare and Inconel 625 films. Enhanced remanent polarization of 60 µC/cm2 was confirmed for the PZT films on ns-CN/metal substrates, ascribed to the preferential alignment of the polar [001] axis normal to the substrate surface, although it also suffered from higher coercive field above 500 kV/cm caused by PZT/metal interfacial reaction.

Ultrahigh strain and piezoelectric behavior in relaxor based ferroelectric single crystals Journal of Applied Physics 82, 1804 (1997) Lead zirconate titanate (PZT) film with polar axis orientation was grown on a SUS 316L stainless steel substrate with the help of a Ca 2 Nb 3 O 10 nanosheet (ns-CN) layer that had a pseudo-perovskite-type crystal structure. The ns-CN buffer layer was supported on a platinized SUS 316L (Pt/SUS) substrate, followed by chemical solution deposition (CSD) of the PZT films with tetragonal symmetry (Zr/Ti =40/60). The PZT films consisting of c-domain, with [001]-axis orientation of the perovskite unit cell, were deposited on the ns-CN/Pt/SUS substrate owing to (i) epitaxial lattice matching between the unit cell of PZT and substrate surface and (ii) in-plane thermal stress applied to the PZT film during cooling-down step of CSD procedure. The c-domain-oriented PZT film on ns-CN/Pt/SUS substrate exhibited enhanced remanent polarization of approximately 52 µC/cm 2 and lowered dielectric permittivity of approximately 230, which are superior to those of conventional PZT films with random crystal orientation and comparable to those of epitaxial PZT films grown on (100)SrRuO 3

One-axis-oriented BiFeO 3 (BFO)-based films were fabricated on platinized silicon and SUS 316L substrates using nanosheets of calcium niobate (ns-CN) with pseudo-perovskite crystal structure. Ca 2 Nb 3 O 10 nanosheets (ns-CNs) were supported on the substrates by dip coating, followed by chemical solution deposition (CSD) of Mn-doped BFO (Mn-BFO) films. Preferential crystal growth of (100)-oriented BFO films was achieved on both ns-CN/(111)Pt/TiO 2 /(100)Si and ns-CN/(111)Pt/SUS316L substrates. The out-of-plane lattice parameters of the BFO films on ns-CN/(111)Pt/SUS316L were larger than the parameter reported for BFO bulk because of elastic deformation caused by thermal stress between the BFO films and SUS316L substrate, whereas those of the films on ns-CN/(111)Pt/TiO 2 /(100)Si were smaller than the reported value. The remanent polarization of the Mn-BFO films was enhanced to approximately 60¯C/cm 2 on ns-CN/(111)Pt/SUS316L because of the compressive thermal stress that causes elastic elongation of Mn-BFO crystals to align or change the tilt angle of their polar axes for the substrate surface.

The machining accuracy of ultra-precision machine tools relies on the performance of the spindle and linear table. The machining accuracy of ultra-precision machine tools is now at the level of several tens of nanometers. In order for ultra-precision machine tools to achieve machining accuracy, a precise spindle system is indispensible. High bearing stiffness is particularly important to minimize displacement due to the cutting force. This paper considers a spindle design supported by high-stiffness water hydrostatic thrust bearings. An objective of this study is to design a precision spindle supported by water hydrostatic thrust bearings with 1 kN/µm bearing stiffness. The bearing restrictors are chosen so that the highest stiffness can be obtained for given bearing parameters. The influences of gap sizes and supply water pressure on the bearing stiffness are presented. Based on the feasibility study done on the design of highstiffness water hydrostatic thrust bearings, the spindle is designed and developed. The influences of the water pressure on the spindle deformation and bearing stiffness are also investigated.

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