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Electrostatic atomization minimum quantity lubrication (EMQL) technology has been developed to address the need for environmentally friendly, efficient, and low-damage grinding of challenging titanium alloy materials. EMQL leverages multiple physical fields to achieve precise atomization of micro-lubricants, enabling effective lubrication in high temperature, high pressure, and high-speed grinding environments through the use of electric traction. Notably, the applied electric field not only enhances atomization and lubrication capabilities of micro-lubricants but also significantly impacts heat transfer within the grinding zone. In order to explore the influence mechanism of external electric field on spatial heat transfer, this paper first comparatively analyzes the grinding heat under dry grinding, MQL, and EMQL conditions and explores the intensity of the effect of external electric field on the heat transfer behavior in the grinding zone. Furthermore, the COMSOL numerical calculation platform was used to establish an electric field-enhanced (EHD) heat transfer model, clarifying charged particles' migration rules between poles. By considering the electroviscous effect, the study reveals the evolution of heat transfer structures in the presence of an electric field and its impact on heat transfer mechanisms. [ABSTRACT FROM AUTHOR]

In this paper, anatase TiO2 nanoparticles (14 nm) were coated on the surface of piezoelectric PbTiO3 single crystal fibers by a secondary hydrothermal method, thus a p‐n junction was formed at the interface between TiO2 and PbTiO3. The PbTiO3 fibers were exposed to an external force (by ultrasound) to generate a dynamic piezoelectric electric field in the crystal, which incessantly separates the carriers and improves the photocatalytic efficiency of TiO2. When the ultrasonic frequency is 40 kHz, the TiO2/PbTiO3 fibers have the highest photocatalytic degradation efficiency (96%) for methylene orange (MO), which is up to 60% improvement compared to TiO2 nanoparticles. [ABSTRACT FROM AUTHOR]

0.96Pb(Ni1/3Nb2/3)O3-0.04PbZrO3(PNN-PZ) ceramics prepared via columbite method exhibit high crystallinity and high density, typical relaxor behavior is demonstrated by the dielectric data. The high dielectric tunability (˜87%) and low dielectric loss (˜0.007) were obtained for PNN-PZ at room temperature around 30kV/cm and 1 kHz, at fields below 13kV/cm, a double-wells model work well between tunability and dc bias electric field, in contrast, at all fields, the thermodynamic model can do better in fitting the dielectric nonlinear tunability behavior of the PNN-PZ ceramics than the double-wells model. These properties indicate that PNN-PZ ceramics might be a promising candidate for tunable materials. [ABSTRACT FROM PUBLISHER]

Abstract: Energy-storage properties of [(Bi1/2Na1/2)0.94Ba0.06]La(1−x)Zr x TiO3 (BNT-BLZT, x=0, 0.02, 0.04, and 0.06) lead-free anti-ferroelectric ceramics fabricated via the conventional sintering technique were first investigated. Calculation from the X-ray diffraction results reveals that BNT-BLZT ceramic possesses a single perovskite structure phase. In addition, the P–E hysteresis loops measured at room temperature show that the BNT-BLZT (x=0.02) ceramics obtain the maximum P value of 37.5μC/cm2 and the largest energy-storage density W max is 1.58J/cm3. The temperature dependence of dielectric permittivity ε r and dielectric loss tanδ illustrate that the addition of Zr can improve the piezoelectric properties of BT-BLZT ceramics. These properties indicate that BNT-BLZT ceramics might be a promising lead-free anti-ferroelectric material for energy storage application. [Copyright &y& Elsevier]

Systematic industrial experiments were carried out to investigate the characteristics of non-metallic inclusions with the aim of reducing their harmful effect on SAE4145 steel properties. Factsage thermodynamic software was used to simulate the conditions under which the inclusions occur. The number of inclusions in molten steel decreased rapidly with refining time. The inclusion morphology changed from an irregular initial shape to predominantly spherical inclusions. After vacuum treatment, almost all of the inclusions were CaO-SiO2-Al2O3-MgO composites. To form low melting point inclusions of CaO-SiO2-20%Al2O3-MgO, the corresponding activities of [O], [Ca], [Mg] and [Al] should be controlled in the range of a[O] 0-10 ppm, a[Ca] 0-45×10-10 ppm, a[Mg] 0-0.3 ppm, and a[Al] 0~20 ppm. [ABSTRACT FROM AUTHOR]

The current work aims to compare the effects of systematic A-site substitutions on the electrical properties of potassium sodium niobate (KNN)-based coating. The A-site elements were replaced by Li+ to form (K0.4675Na0.4675Li0.065) NbO3 (KNLN). The pure KNN coating and the Li+-doped potassium sodium niobate (KNLN) coating with dense morphology and single perovskite structure were successfully prepared by supersonic plasma spraying, and the phase composition, microscopic morphology and electrical properties of the two coatings were compared and analyzed in detail by XRD, XPS, three-dimensional morphology and SEM on an Agilent 4294A (Santa Clara, CA, USA) and FE-5000 wide-range ferroelectric performance tester. The results show that: as the polarization voltage increases, the pure KNN coating is flatter and fuller, but the leakage current is large. The KNLN coating has a relatively long hysteresis loop and is easily polarized. The domain deflection responds faster to the external electric field, and the resistance of the domain wall motion to the external electric field is small. The dielectric constant of KNLN coating is 375, which is much higher than that of the pure KNN coating with 125, and the dielectric loss is stable at 0.01, which is lower than that of pure KNN coating at 0.1–0.35. This is because Li+ doping has successfully constructed a polycrystalline phase boundary in which O-T phases coexist, and has higher dielectric properties, piezoelectric properties and ferroelectric properties. At the same time, due to the high-temperature acceleration process in supersonic plasma spraying, the violent volatilization of the alkaline elements Li+, Na+ and K+ leads to the presence of oxygen vacancies and part of Nb4+ in the coating, which seriously affects the electrical properties of the coating. [ABSTRACT FROM AUTHOR]