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The NiTi claddings by tungsten inert gas (TIG) with Ni and Cu interlayer were manufactured to resist the cavitation erosion-corrosion (CEC). The cavitation test, the open circuit potential and the potentiodynamic polarization measurements were used to study the synergistic effect among cavitation erosion (CE) and corrosion for the NiTi claddings. After the CEC test for 11h, the cumulative mass loss of 304 stainless steel is 5 and 1.15 times that of NiTi-Ni-TIG cladding and NiTi-Cu-TIG cladding, respectively. In NiTi-Cu-TIG cladding, the galvanic corrosion between the Cu-Ti intermetallics and the B2 phase causes the anodic dissolution of the Cu-Ti intermetallics, and results in the B2 phase losing support and spalling off during the CEC test. In contrast, NiTi-Ni-TIG cladding can be used against the CEC because of its uniform microstructure, no Cu-rich area and the effect of corrosion on CE of NiTi-Ni-TIG cladding is small.

Diffusion bonding of AA7075/AZ80 joint has been synthesized, studied and demonstrated to optimize the lap shear, Ram tensile and hardness properties. Response surface methodology (RSM) is applied to develop mathematical relationships between the control parameters of two factors and three-level responses. Optimization experiments were carried out to check the models’ adequacy. The results show a high degree of coincidence between the optimized and actual values, implying that the proposed models can accurately forecast lap shear, Ram tensile, and hardness properties force within the process parameter constraints of the diffusion bonding process. Scanned electron microscopic Scanning Electron Microscope (SEM) images, optical images, and radiography film photography investigations also revealed the excellent fracture resistance of the AA7075/AZ80 alloy, making it a suitable material for deployment in engineering applications.

A systematic investigation has been performed regarding the mechanisms that lead to damage of dissimilar laminated construction, with a different stacking sequence. Also, such construction of materials involving glass/polymer is used in blast-proof safety screens or bullet-proof windows or windshields in automobiles, architectural glazing, aerospace and aeronautical fields. In many cases, the laminated plate can be effectively used if it has properties such as high-performance and a low specific weight. In this work, the impact induced damages in glass/PMMA and PMMA/glass, and laminated circular plates with an upside-down stacking sequence are investigated by using an instrumental long bar impact tester in a biaxial bending state. In order to improve the damage tolerance of other types of laminated circular plates, various geometric (ratio of inner to outer layer thickness) and stacking sequence parameters were considered in determining their effect in absorbing an impact. The measured impact force profiles and the impulse of the force explained the impact damage behavior that is induced in dissimilar laminated circular plates. We have shown that a stacking sequence could have an effect on the initiation of radial cracks and in the impact damage area of laminated plates, in inner and outer layers. Also, the greater the inner layer thickness, the less damage the areas sustain. A design guideline of a stacking sequence is proposed for effective dissimilar laminated plate construction.

Radial stress distribution and plastic damage zones evolution in ceramic coating/metallic interlayer/ductile substrate systems under spherical indentation were investigated numerically by axisymmetric finite element analysis (FEA) for a typical ceramic coating deposited on carbon steel with various indenter radius-coating thickness ratios and interlayer thickness-coating thickness ratios. The results showed that the suitable metallic interlayer could improve resistance of ceramic coating systems through reducing the peak tensile radial stress on the surface and interface of ceramic coatings and plastic damage zone size in the substrate under spherical indentation.

CVD diamond coating was deposited on to 13%wt. Co-containing tungsten cemented carbide surfaces using a hot filament chemical vapor deposition (HFCVD) to improve wear properties and performance of WC-13%wt.Co. Prior to the deposition of the diamond films, a W-C gradient intermediate layer had been sputtered on WC-13%wt.Co. The surface and cross-section morphology, phase transformation, and grain size distribution of the samples were investigated by means of field emission scanning electron microscope (SEM), X-ray diffractometer (XRD), and atomic force microscope (AFM), respectively. The results show that W-C gradient intermediate layers can effectively reduce the diffusion of Co in cemented carbide substrates during diamond deposition process, resulting high nucleation density and ultra smooth nanocrystalline diamond films.

The influence of an AlO_x oxide or Si interlayer on the thermoelectric power factor of the higher manganese silicide (HMS, MnSi_y, y = 1.73–1.75) film deposited on quartz substrate is investigated. The HMS film and the interlayer are prepared on quartz substrate by magnetron sputtering of MnSi₂, Al, Si and Si:B (1 at.% B content) targets. It is found that the metallic phase MnSi is present in the semiconducting HMS film without an interlayer, resulting in a lower Seebeck coefficient, 0.160 mV/K, but not a lower electrical resistivity, 0.021 Ω ⋅cm at 683 K. The thermoelectric power factor is only 122 × 10^-6 W/mK² at 683 K. On the other hand, the metallic phase MnSi disappears and the Seebeck coefficient restores to its high value after using the AlO_x oxide or Si interlayer. Besides, the electrical resistivity decreases by using the AlO_x oxide or Si:B interlayer. The HMS film with an Si:B interlayer has the highest Seebeck coefficient, 0.247 mV/K, and the lowest electrical resistivity, 0.011 Ω ⋅cm, at 683 K. Thus, the thermoelectric power factor is enhanced and can reach 555 × 10^-6 W/mK² at 683 K.

In this paper, we fabricated Pt/TiO_x/ZnO/n⁺-Si structures by inserting TiO_x interlayer between Pt top electrode (TE) and ZnO thin film for non-volatile resistive random access memory (ReRAM) applications. Effects of TiO_x interlayer with different thickness on the resistance switching of Pt/TiO_x/ZnO/n⁺-Si structures were investigated. Conduction behaviors in high and low resistance state (HRS and LRS) fit well with the trap-controlled space-charge-limited conduction (SCLC) and Ohmic behavior, respectively. Variations of set and reset voltages and HRS and LRS resistances of Pt/TiO_x/ZnO/n⁺-Si structures were investigated as a function of TiO_x thickness. Switching cycling tests were attempted to evaluate the endurance reliability of Pt/TiO_x/ZnO/n⁺-Si structures. Additionally, the switching mechanism was analyzed by the filament model.

The finite element method (FEM) is employed to analyze the residual stress distribution of bi-layer (a-SiC $+$ diamond) film system, and the adhesion enhancement mechanism of a-SiC interlayer is further investigated. The influence of a-SiC interlayer on the surface topography of WC-Co substrate is taken into consideration by adopting a 3D surface topography model agreeing with the Atomic Force Microscope (AFM) characterization of a-SiC interlayer. For the sake of comparison, the stress distribution of a diamond film with no interlayer is also simulated. The simulation analysis reveals that the residual stress distribution is much more homogeneous after employing the a-SiC interlayer, which is supposed to be of great importance to the adhesion enhancement of diamond films. Afterwards, the diamond films with and without a-SiC interlayer are fabricated on WC-Co substrates. Raman mapping is carried out to measure the real residual stress distribution of as-fabricated a-SiC diamond films, which is in accordance with the simulation results. Moreover, the a-SiC interlayered diamond film exhibits better adhesion than the diamond film with no interlayer in adhesion evaluation, which can be ascribed to the more homogeneous residual stress distribution and better interfacial bonding after introducing the a-SiC interlayer.

In this study, the effect of diamond interlayer on the tribological properties of titanium aluminum nitride (TiAlN) film sliding against medium carbon steel is investigated in dry rotary friction tests, by evaluating the coefficients of friction (COFs), wear rates, worn surfaces and element transitions of the contacted surfaces in the cemented carbide (WC-Co)-steel, TiAlN-steel, microcrystalline diamond (MCD)-steel, TiAlN/MCD-steel, micro- and nano-crystalline diamond (MNCD)-steel and TiAlN/MNCD-steel contacting pairs. It is found that compared with the TiAlN monolayer, the TiAlN/MCD bilayer film shows 57% higher COF, while the COF of TiAlN/MNCD multilayer inversely drops as much as 54%, due to the distinguished surface diamond grain morphologies of the MCD and MNCD interlayers as well as the copied effect of the TiAlN layer with relatively small thickness. Meanwhile, the diamond interlayer can provide robust load support for the top TiAlN layer, induce the wear mechanism transform from the abrasive wear to adhesive wear, and result in the mild wear of TiAlN/MCD and TiAlN/MNCD multilayers compared to the TiAlN monolayer. Moreover, the softer TiAlN top layer on MCD and MNCD interlayers can effectively improve the storage capacity of element oxygen and worn steel ball debris as well as accelerating the surface chemical reactions to form a smoother continuous ionic metal oxides tribofilm in the contacted zones due to its good self-lubricating property. Among all the hard coatings discussed when sliding against medium carbon steel, the TiAlN/MNCD coating shows the lowest COF and mild wear, due to the robust load support capacity of the beneath MNCD layer as well as the good self-lubricated and tribofilm formation capacity of the top TiAlN layer, which shows broad application potential in carbon steel machining.

In this study, the diamond films are deposited on tungsten carbide substrates with 10wt.% Co via hot filament chemical vapor deposition (HFCVD). Amorphous SiC (a-SiC) interlayers with various thicknesses are fabricated between the diamond films and tungsten carbide substrates via precursor pyrolysis to promote the adhesion and friction performance of diamond films. Indentation tests are performed to evaluate the adhesion of the as-fabricated diamond films, which show that the a-SiC interlayers can greatly improve the adhesive strength between diamond films and tungsten carbide substrates with 10wt.% Co. Moreover, the thickness of a-SiC interlayer is of great importance for the effectiveness on the film–substrate adhesion enhancement. The optimum thickness of a-SiC interlayer is 1$\mu$m. Afterwards, ball-on-disc experiments are chosen to check the tribological properties of the as-fabricated a-SiC interlayered diamond film specimen with the optimum interlayer thickness, which exhibits lower friction coefficient than the conventional diamond film with no interlayer.

A model of a heterophase sample with interlayers is proposed to describe coexistence of tetragonal and orthorhombic phases in lead-free perovskite-type ferroelectric solid solutions. Versions of phase coexistence are analyzed at variations of unit-cell parameters of (Ba, Ca)(Ti, Zr)${\mathrm{\text{O}}}_3$ and (K, Na)(Nb, Sb)${\mathrm{\text{O}}}_3$-(Ba, Ca)${\mathrm{\text{ZrO}}}_3$ with compositions near morphotropic phase boundaries. Large regions of the tetragonal and orthorhombic phases are split into $90^{\circ }$ and $120^{\circ }$ domains, respectively. The interlayer of the orthorhombic phase is either single-domain or split into $90^{\circ }$ domains. A complete stress relief can be achieved at an elastic matching of the polydomain/single-domain or polydomain/polydomain phases. It is shown that different phase contents in (${\mathrm{\text{Ba}}}_{0.85}{\mathrm{\text{Ca}}}_{0.15}$)$\cdot \cdot$(${\mathrm{\text{Ti}}}_{0.9}{\mathrm{\text{Zr}}}_{0.1}$)${\mathrm{\text{O}}}_3$ powder and ceramic are caused by different non-${180}^{\circ }$ domain structures in the phases. The interlayer of the orthorhombic phase plays an important role in forming the phase content in solid solutions. Agreement is shown when comparing the evaluated volume fractions of the orthorhombic phase to experimental data.

Joining of metal with ceramics has become significant in many applications, because they combine properties like ductility with high hardness and wear resistance. By friction welding technique, alumina can be joined to mild steel with AA1100 sheet of 1mm thickness as interlayer. In the present work, investigation of the effect of friction time on interlayer thickness reduction and bending strength is carried out by factorial design. By using ANOVA, a statistical tool, regression modeling is done. The regression model predicts the bending strength of welded ceramic/metal joints accurately with ± 2% deviation from the experimental values.

To investigate the mechanical behaviour of laminated glass with the elasto-viscoplastic ionomer interlayer SentryGlas® by DuPont, an experimental program was executed on full-scale glass laminates. The results of this research improved the insight in the complex mechanical behaviour of this stiff interlayer. More specifically, a clear influence of load duration and temperature could be observed for both creep and relaxation during torsion experiments. Namely, within the tested temperature range of 5 °C up to 65 °C, torsional stiffness changed with a factor 3.

To investigate the mechanical behaviour of laminated glass with the elasto-viscoplastic ionomer interlayer SentryGlas® by DuPont, an experimental program was executed on full-scale glass laminates. The results of this research improved the insight in the complex mechanical behaviour of this stiff interlayer. More specifically, a clear influence of load duration and temperature could be observed for both creep and relaxation setups during bending experiments. The stiffness reduction due to the load duration and the temperature raise was most significant for the smaller specimens — with a span of 1m — while for the largest specimen — with a span of almost 3 meter — the reduction remained less than 25% of the monolithic bending stiffness, even after a load duration of 48 hours at 65°C.