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The interfacial adhesive properties of polypropylene/stainless steel were studied by the blister test. The polypropylene film with a squared free-standing window was pressured by oil from one side of film. The corresponding deformation field was observed by a digital speckle correlation method. The experimental results show that the squared film deforms and debonds from stainless steel with the increase of pressure. The debonding of the squared film in initiates from the center of edge and extends to the corner, and then the deformation of film evolves from square to circle shape. The interfacial adhesive energy of polypropylene/stainless steel is (22.60±1.55) J/m 2 , which is in agreement with that measured by film with a circular window.

Bi0.9La0.1Fe0.95Mn0.05O3 (BLFMO) ferroelectric thin films were fabricated on Pt/Ti/SiO2/Si/substrates by the sol-gel process at different pyrolysis temperatures. The mass loss of BLFMO powder was investigated by thermo gravimetry analyser (TGA), and the polycrystalline structure and smooth surface of BLFMO thin films were characterized by X-ray diffraction (XRD) and atomic force microscopy (AFM), respectively. The remnant polarization (Pr) of the BLFMO films pyrolyzed at 420°C is 21.2 μC/cm2 at the coercive field (Ec) of 99 kV/cm and the leakage current density is 7.1×10−3 A/cm2, which indicates that the BLFMO thin films display relatively good ferroelectric property at this temperature.

To characterize the elastic-plastic properties of thin film materials on elastic-plastic substrates, a simple theory model was proposed, which included three steps: dimensionless analysis, finite element modeling and data fitting. The dimensionless analysis was applied to deriving two preliminary nondimensional relationships of the material properties, and finite element modeling and data fitting were carried out to establish their explicit forms. Numerical indentation tests were carried out to examine the effectiveness of the proposed model and the good agreement shows that the proposed theory model can be applied in practice.

Bi3.15Nd0.85Ti3O12 (BNT) powder and thin film were prepared by metal organic decomposition (MOD) method. The heat flow curve of BNT powder was measured with a modulated temperature differential scanning calorimeter, and thermal physical parameters such as thermal conductivity coefficient and thermal diffusion coefficient were obtained from the heat flow curve. The phase identification, ferroelectric, and piezoelectric properties of BNT thin film annealed at 700℃ were investigated with X-ray diffractometer, ferroelectric analyzer, and scanning probe microscope. The results show that the thin films consisting of a single phase of bismuth-layered perovskite are polycrystalline, without a preferred orientation. Remnant polarization 2P(subscript r) is 63.2μC/cm^2 under 530 kV/cm applied field, and the effective piezoelectric coefficient d33 is 30 pm/V.

Nanocrystalline nickel films of 17–40 nm grain sizes were prepared using pulsejet electrodeposition. Structure, corrosion and lattice strain were analysed by transmission electron microscope, electrochemical workstation and X-ray diffraction, revealing that with decreasing of grain size, the lattice strain, corrosion rate of the films are enhanced. The observations can be consistently understood in terms of the bond-order-length-strength correlation mechanism indicating that the shortened and strengthened bonds between the under-coordinated atoms modify the energy density and the atomic cohesive energy in the surface skins of the grains. The surface energy density gain is responsible for the residual atomic cohesive energy for the activation energy of corrosion. Additionally, a novel algorithm was proposed to extract the elastic-plastic properties of nickel films and results that the nickel film has much higher yield strength than bulk nickel.

The forming limits of nickel coating on the right region were studied, so as to direct the preparation of the material and help the production of workpieces. The electrodeposited nickel coating was prepared on steel substrate to form advanced structures, and its plastic instability was investigated by the Swift Plastic Instability Theory. By using the compound law for laminated sheet metals, explicit equations for the calculation of the instable eigen values were deduced. The forming limit diagrams of the nickel coating on the right region were plotted. It is exhibited that the forming limit of the coating sheet is between the forming limits of the individual nickel coating and steel substrate. The forming limit of the nickel coating is not so good as that of the steel substrate, and the forming limit strain of the coating sheet tends to diminish with the increase of thickness of the coating. The greater the normal anisotropic coefficient of the materials is, the better the forming limit is.

Dysprosium-doped Bi 4 Ti 3 O 12 (Bi 3.4 Dy 0.6 Ti 3 O 12 BDT) ferroelectric thin films were deposited on Pt(111)/Ti/SiO 2 /Si(111) substrates by chemical solution deposition (CSD) and crystallized in nitrogen, air and oxygen atmospheres, respectively. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to identify the crystal structure, the surface and cross-section morphology of the deposited ferroelectric films. The results show that the crystallization atmosphere has significant effect on determining the crystallization and ferroelectric properties of the BDT films. The film crystallized in nitrogen at a relatively low temperature of 650 °C, exhibits excellent crystallinity and ferroelctricity with a remanent polarization of 2 P r = 24.9 μC/cm 2 and a coercive field of 144.5 kV/cm. While the films annealed in air and oxygen at 650 °C do not show good crystallinity and ferroelectricity until they are annealed at 700 °C. The structure evolution and ferroelectric properties of BDT thin films annealed under different temperatures (600–750 °C) were also investigated. The crystallinity of the BDT films is improved and the average grain size increases when the annealing temperature increases from 600 °C to 750 °C at an interval of 50 °C. However, the polarization of the filas is not monotonous function of the annealing temperature.

The possibility of ultra-thin Y2O3 (yttrium sesquioxide) films as insulator of metal ferroelectric insulator semiconductor (MFIS) structure was investigated. The ultra-thin Y2O3 films with thickness of 10–40 nm were fabricated on p-type Si (100) substrates by molecular beam epitaxy(MBE) in vacuum and subsequently submitted to rapid thermal processing (RTP) in air ambient at 700, 800 and 900 °C for 30 min, respectively. The films were characterized by X-ray diffractometry and Raman spectroscopy. High frequency capacitance—voltage (C—V) characteristics and current—voltage (I—V) characteristics of the Y2O3/Si structure were analyzed. A Raman peak of the Y2O3 thin films was observed at 378 cm−1. From the C—V data, these films exhibit dielectric constants ranging from 13 to 17.28, the hysteresis width (ΔVFB) ranging from 0.07 to 0.22 V and the density of trapped charges ranging from 1.65×1011 to 4.01×1011 cm−2. A leakage current of 4.75×10−8−9.0×10−6 A/cm2 at 1.5 MV/cm was observed. The results show that the Y2O3 buffer layers are suitable for non-volatile MFIS structure field-effect-transistors (FETs) memory application.

The deformation-induced textures in electrodeposited nickel coating were numerically studied. The finite element method (FEM) for polycrystalline was developed based on Taylor model. Then the deformation-induced textures in electrodeposited nickel coating with initial random and lamellar texture were simulated under tensile load. It is found that the initial textures significantly influence the deformation-induced textures. For nickel coating with the initial random textures, when the tensile strain is about 40%, there are some lamellar textures. For nickel coating with the initial lamellar textures, the lamellar texture is more intensity with the increase of the tensile strain. With the increase of the tensile strain in the coating, there are more pronounced element distortion and a more inhomogeneous deformation. Due to the different crystal orientations, the grain-scale roughness is observed. With increasing tensile strain in the coating, the surface grain-scale roughness increases on the free surface. The surface roughness of the coating with initial random texture is lower than that with the initial lamellar texture.

The wavelet transform is applied to the analysis of acoustic emission signals collected during tensile test of the ZrO2-8% Y2O3 (YSZ) thermal barrier coatings (TBCs). The acoustic emission signals are de-noised using the Daubechies discrete wavelets, and then decomposed into different wavelet levels using the programs developed by the authors. Each level is examined for its specific frequency range. The ratio of energy in different levels to the total energy gives information on the failure modes (coating micro-failures and substrate micro-failures) associated with TBCs system.

An analytical method was proposed to solve the mechanical problems of stamping a thin strip on an elastic foundation. The thin strip was divided into four parts according to its deformation and contact with the punch and the elastic foundation, especially an elastic-plastic part was considered in the deflection of the thin strip. Analytical solutions were derived individually for each part and two models were established with the help of elastic and plastic large deflection theories. Compatibility conditions between the neighboring parts of the thin strip constructed the non-linear equation group. Solutions were carried out by programming with a software. The deformation shape, the membrane force, and the moment and shear force of the deformed thin strip were obtained. The results of the two models were compared. The study shows that the method is effective.