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Due to the error between the strain measured by the fiber grating sensor pasted on the surface of the substrate and the real strain of the substrate, the analysis of the relationship between the strain measured by the fiber and the actual strain of the substrate is the focus of this research. Since structures are subjected to various harsh conditions in actual service, such as temperature changes, fatigue, corrosion, aging, cracks and other external factors, when using surface-adhesive fiber Bragg grating (FBG) sensors for structural health monitoring, all external factors may affect the measurement accuracy of the sensors and cause measurement errors, so it is necessary to consider some specific factors in a comprehensive manner. In this paper, we theoretically study the average strain transfer rate of the three-layer strain transfer model of a surface-adhesive fiber grating sensor under the effects of temperature change and fatigue load, derive the formula for the average dynamic strain transfer rate under the combined effects of two external factors using the shear-lag method and analyze the parameters of the fiber-optic sensor to correct the error and optimize the measurement accuracy of the sensor in order to better monitor the structure under temperature change and fatigue load. The shear hysteresis method is also used to analyze the parameters of the fiber-optic sensor to correct the errors and optimize the measurement accuracy of the sensor in order to better monitor the real dynamic strain of the substrate under temperature and fatigue loads and provide theoretical guidance for its measurement.

In this paper, an experimental investigation of the machinability of Titanium grade 23 has been carried out using hybrid micro-textures on the cutting tool. The different types of micro-textures have been fabricated on the rake surface as well as on the flank surface of the cutting tool. The performance of textured tools with the presence of a chip breaker has been investigated. The selected patterns were vertical grooved rake face (VT-R), diagonal grooved rake face (DT-R), vertical grooved flank face (VT-F) and hybrid textured tools namely, vertical rake and flank (V+V), diagonal rake and vertical flank (D+V). A comparative study has been carried out to acknowledge the performance of textured tools while dry turning Titanium Grade 23 alloy. The machinability has been made to acknowledge the performance of textured tools with the variation of machining time in case of dry turning operation. The machinability criteria are investigated based on cutting forces, cutting temperature and tool wear mechanisms involved while machining. The performance of the cutting tool with DT-R and VT-F micro-texture is observed to be better in comparison to others. Innovative applications of micro-textured tools are for dry green machining without any environmental hazards and proper chip-flow control.

Ferroelectric ceramics, such as barium titanate, have garnered significant interest due to their unique electrical and mechanical properties. In particular, their ability to undergo significant deformation under an applied electric field aids in their utilization in many applications, including actuators and sensors. The deformation behavior of ferroelectric ceramics is complex and is influenced by various factors, such as crystal structure, defect density, and processing conditions. This study focuses on the mechanics of ferroelectric ceramics and seeks to offer a thorough comprehension of the barium titanate’s deformation behavior. The study begins by discussing the crystal structure of barium titanate and how it influences the ferroelectric behavior of the material. It then delves into the various mechanisms of deformation, including domain wall motion, phase transformation, and twinning. The study also discusses the effects of temperature, electric field strength, and microstructure on the deformation behavior of barium titanate. Furthermore, the study explores the relationship between the deformation behavior and the mechanical characteristics of barium titanate, including Poisson’s ratio and Young’s modulus. Finally, the study concludes with a discussion of the potential applications of ferroelectric ceramics and the need for further research in this area. Overall, this study provides a comprehensive understanding of the deformation behavior of barium titanate showcasing distinct influences of grain size, texture, and anisotropy. Notably, varying grain sizes significantly impact deformation behavior. For instance, smaller grain sizes ($<10\mu$m) exhibit superior deformation characteristics, correlating with higher permittivity values (2731–5801) compared to larger grain counterparts (18.4$\mu$m). Additionally, transition temperatures ($T_{\mathrm{\text{O}}–\mathrm{\text{T}}}$) for different grain sizes (18.0–$30.1^{\circ }$C for smaller grains, 21.5–$30.6^{\circ }$C for larger grains) underscore the impact of phase transitions on grain size. These results underscore the paramount importance of grain size, texture, and anisotropy in governing the mechanical traits of barium titanate, emphasizing their consideration during fabrication and processing for optimal performance in diverse applications.

Polycrystalline Bi_0.975La_0.025Fe_0.975Ni_0.025O₃ (BLFNO) film is fabricated on Pt/Ti/SiO₂/Si(111) substrate by sol–gel method. It is found that the well-crystallized BLFNO film is polycrystalline, and the Pt/BLFNO/Pt capacitor possesses good ferroelectric properties with remnant polarization of 74 μC/cm² at electric field of 833 kV/cm. Moreover, it is also found that the leakage current density of the Pt/BLFNO/Pt capacitor increases with the increase of measurement temperature ranging from 100 to 300 K. The leakage density of the Pt/BLFNO/Pt capacitor satisfies space-charge-limited conduction (SCLC) at higher electric field and shows little dependence on voltage polarity and temperature, but shows polarity and temperature dependence at lower applied electric field. With temperature increasing from 100 to 300 K at lower applied electric field, the most likely conduction mechanism is from Ohmic behavior to SCLC for positive biases, but no clear dominant mechanism for negative biases is shown.

The present paper report the results of an experimental investigation of the temperature effect on the sliding friction and wear properties of the bulk metallic glass (BMG). To improve the friction and wear properties of the BMG, the disk specimens were developed in the alloy system of Fe_67.6C_7.1Si_3.3B_5.5P_8.7Cr_2.3Mo_2.6Al₂Co_1.0 using hot metal and industrial ferro-alloys. The friction and wear test was performed using flat-on-flat contact configuration of unidirectional tribometer and Si₃N₄ ceramic disk used as a counterpart. The worn surfaces of the BMG were observed by using scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS). The results indicated that the friction and wear properties of the BMG depend on the glass transition and the formation of protective oxide film. The friction coefficient decreased with increasing temperature, while it increased slightly when the temperature passed the glass transition temperature (T_g). The worn specimens were exposed to abrasion, adhesion, oxidation and plastic deformation. In addition, obvious surface flow characteristics was accompany during wear test.

This study investigates the effects of sliding ratio on the tribological response of the contact between the teeth of a metal/polymer gear in the regions close to the pitch point. For this purpose, a new twin-disc test rig was developed on the basis of two discs of different diameters rotating one above the other at the same angular speed. Two different materials were used: non-alloyed structural steel (C45) and polyamide (PA66). The effect of the slip ratio (4%, 12%, 20% and 28%) was studied at a constant pressure of 34 MPa and a constant angular speed of 300 rpm. In addition, the contact conditions were controlled with measurements of the two discs surface temperatures. The results indicate that the wear and the friction are closely related to the contact temperature generated by the sliding phenomenon. At low slip ratio (4% and 12%), the coefficient of friction and the temperature are characterized by a quasi-linear increase with time, and the wear increases slowly. At higher slip ratio (20% and 28%), the coefficient of friction and the temperature presents a steady state, and the wear increases dramatically. During the test, a film of transferred PA66 is formed on the steel surface causing the development of adhesive interactions between the contacting discs which increase the friction coefficient and the contact temperature. The high thermal conductivity of steel as compared to that of the polymer can reduce enormously the contact temperature generated by the sliding process.

In this work, the potential of tin (IV) 2,3-napthalocyanine dichloride (SnNcCl₂) has been studied for sensing applications due to its hydrophobic nature. The multipurpose sensor was fabricated by depositing 50-nm silver (Ag) electrodes on a glass substrate through vacuum thermal evaporation at pressure of $\sim 10^{-5}$ mbar. With the help of masking, a 40-micron inter-electrode gap between Ag electrodes was developed and then 80-nm film of SnNcCl₂ was thermally deposited in the inter-electrode gap resulting in a surface type Ag/SnNcCl₂/Ag multipurpose sensor and was studied for humidity and temperature sensing. The humidity characterization was carried out at two different frequencies, i.e. 120 and 1kHz in the relative humidity range 35–85% RH and 5.5 and 1.3 times increase was recorded with respect to initial capacitance for both frequencies, respectively. The temperature sensing was studied within a temperature range of 15–80^∘C at 120Hz frequency and 1.3 times increase in capacitance was observed with respect to initial capacitance. The sensor’s important parameters, i.e. response time and recovery time were measured to be 8 and 3s at 120Hz for humidity measurements. The morphology of the SnNcCl₂ thin film was measured by atomic force microscope (AFM) and scanning electron microscope (SEM) showing rough surface favorable for sensing applications. The amorphous structure of the film was confirmed by X-ray diffraction (XRD) while optical bandgap was calculated from ultraviolet-visible (UV-vis) spectroscopy.

In this paper, pulsed arc ion plating was applied for preparing Ti–Al–N coatings. The effects of different process parameters on the structure and corrosion resistance properties of Ti–Al–N coating were studied by changing the temperature. The microstructures, morphology features and the corrosion resistance of the different temperatures of Ti–Al–N coating were investigated to simulate the corrosion conditions of seawater. All the samples (prepared at $370^{\circ }$C, $375^{\circ }$C, $380^{\circ }$C and $385^{\circ }\text{C})$ were measured in 3.5wt.% NaCl solution at $25^{\circ }$C and characterized by potentiodynamic polarization curves, scanning electron microscopy (SEM) combined with analyzed by X-ray diffraction (XRD). The corrosion resistance of carbon steel was improved by the coating modification. The results showed that the sample prepared at $380^{\circ }$C possesses excellent corrosion resistance where corrosion current density can only reach to 11.176$\mu$A/cm², Meanwhile, SEM images also revealed that the microstructure of the sample is much smoother and nearly no defects can be observed.

Bone grinding is a craniotomy procedure which is used to remove a bone flap from the skull to expose and create an access for the dissection of tumors. In this study, a computer-controlled neurosurgical bone grinding has been used to explore the effect of various neurosurgical bone grinding parameters, such as cutting forces, torque, grinding force ratio, and temperature generated during bone grinding have been investigated. Bone samples after grinding have been assessed for morphological analysis. Based on the outcomes, a multi-attribute decision-making methodology based on grey relational analysis has been adopted. Regression models have been developed and then validated to ensure the adequacy of the developed models. Subsequently, a comparative analysis of experimental and predicted results have been presented. It is revealed that grinding forces and torque decreased with the escalation of rotational speed from 35,000 revolutions per minute (rpm) to 55,000rpm. The optimum combination of process parameters found as rotational speed of 55,000rpm, feed rate of 20mm/min, and depth of cut of 0.50mm.

To study the corrosion behavior of carbon steel in seawater at different temperatures, a novel electrochemical method called gradient-distributed wire beam electrode technique with high temporal and spatial resolution has been employed. This new wire beam electrode was prepared by three kinds of carbon steel with different carbon contents so that it can evaluate three materials simultaneously in the same corrosion medium (3.5wt.% NaCl solution) and improve the accuracy of tests results. After the gradient-distributed wire beam electrode soaked in 3.5wt.% NaCl solution for 8h, compared with measured at room temperature, the corrosion rate was accelerated greatly and polarity reversal of potential-current was also observed.

Machining with minimum quantity lubrication (MQL) or minimum quantity cooling (MQC) as a subset of green machining is a process in which small volume fluid of high lubrication and cooling properties alongside high pressure air is used in the material removal process. The heat generated in the grinding process has a great impact upon the workpiece quality. Serving lubrication and heat transfer functions, cutting fluids have an essential role in reducing the temperature and thus improving the process of grinding. In this research, nanofluid made of graphene nanoparticles in water-based fluid as a cutting fluid of high heat transfer is utilized to investigate the effects of nozzle number and nozzle geometry of the MQC system on the cutting temperature and surface roughness of the workpiece. The effect of geometry and number of nozzles on grinding with MQC has not been studied so far. The study findings show that the nozzle outlet cross-section of rectangular, compared to circular, decreases the surface roughness and temperature by 30% and 36%, respectively. Moreover, compared to the single nozzle, the use of three nozzles results in a decrease of 19% and 31.7% in the surface roughness and temperature. Under the same machining conditions, the MQC method by 0.15wt.% nanofluid of graphene in water using a rectangular nozzle outlet of 1.2mm width makes surface roughness and temperature reduced by 67.2% and 48.3% compared to the dry condition, whereas decreased by 13.4% and 8.8% compared to the wet method, respectively.

The drilling of glass fiber-reinforced plastic (GFRP) composites gained importance since they are used as structural components in many industries such as automotive, aerospace, and aviation. A large number of holes are needed in the industry to join these composite parts. However, some failures occur in drilling GFRP composites, such as delamination, matrix cracking, and fiber breakage. These failures not only reduce the strength of the composite, but also reduce its service life. Drilling parameters, drill bits, and woven types have a great influence on the occurrence of these failures by greatly influencing the thrust force, surface quality, and cutting temperature. In this study, the effects of drilling parameters and woven types of GFRP composites on thrust force, surface roughness, delamination factor, and cutting temperature were examined in the drilling of uni-directional (UD), $\pm 45^{\circ }$ and 0${}^{\circ }∕90^{\circ }$ GFRP woven composites. The effects of drilling parameters and the delamination factor on the tensile strength of the drilled specimen were also investigated. The result of this study indicated that thrust force, delamination factor, and surface roughness increased with increasing cutting speed and feed rate. An increase in feed rate decreased the cutting temperature, while an increase in cutting speed increased the cutting temperature. Also, it was found that the delamination factor had a critical influence on the tensile strength of the GFRP composites.

The machinability of a cutting tool merely depends on cutting temperature, surface finish, and tool life, etc. To investigate the machinability of non-textured plain cutting inserts and micro-textured cutting inserts, various novel micro-textures have been fabricated using a femtosecond laser machine on the rack face of the double-sided square cutting insert without amputating its TiCN coating. The turning operation has been performed on a Titanium Gr 2 rod of diameter 50 mm on a three-jaw self-centered lathe machine. Type of insert, rotational speed, and cutting feed rate are the main parameters with various levels. L27 orthogonal array has been used for the design of experiments. Significant reduction in cutting tool temperature and surface roughness has been observed using micro-textured cutting inserts. The cutting insert with Honeycomb micro-texture gives superior results with a minimum cutting temperature of 210^∘ C and a maximum of 76% improvement in surface finish.

Public transport via trams has become increasingly important in daily life to meet the growing demand for economic and environmental considerations. In order to ensure the safety of the railway system and reduce service costs, it is necessary to understand the tribological behavior of the system. There are various types of damage such as fatigue, wear, and cracking that can harm the wheels and rails. To determine the wear mechanisms and identify the situations in which wear movements occur, it is crucial to monitor factors such as temperature, surface roughness, and contact micro-hardness between the wheel and the rail. The objective of this study is to analyze the tribological behavior and the impact of climatic conditions on the wheel–rail contact system in the desert area of the Ouargla tramway in Algeria. To achieve this, an intelligent sensor programmed by a microcontroller was utilized to measure the temperature of the wheel–rail contact. Additionally, a hardness tester was used to measure the micro-hardness of the rail, and a roughness tester was utilized to monitor the surface condition of the rail. The measured temperature values during the passage of the tramway varied between ambient temperature and a temperature of 450^∘C. The micro-hardness values ranged from 270 Hv to 440 Hv, and the roughness values varied between 0.4$\mu$m and 2.7$\mu$m.