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To enhance the productivity and quality of optical-grade liquid silicone rubber (LSR) and an optical convex lens simultaneously, uniform vulcanization of the molding material is required. However, little has been reported on the uniform vulcanization of LSR in the heated cavity. This paper presents a conformal heating channel to enhance the temperature uniformity of the mold surface in the LSR injection molding. The curing rate of an optical convex lens was numerically investigated using Moldex3D molding simulation software. Two different sets of soft tooling inserts, injection mold inserts with conventional and conformal heating channels, were fabricated to validate the simulation results. The mold surface temperature uniformity was investigated by both numerical simulation and experiment. In particular, both a thermal camera and thermocouples were employed to measure the mold surface temperature after LSR injecting molding. It was found that the uniformity of the mold surface for LSR injection mold with the conformal heating channel was better. The average temperature of the mold surface could be predicted by the heating oil temperature according to the proposed prediction equation. The experimental results showed that the trend of the average temperature of five sensor modes was consistent with the simulation results. The error rate of the simulation results was about 8.31% based on the experimental result for the LSR injection mold with the conformal heating channel.

Liquid silicone rubber (LSR) techniques are experiencing exponential growth, particularly in the field of high technology due to the low-temperature flexibility, superior heat stability, chemical resistance, and aging resistance of LSR components. Enhancing the curing rate of LSR parts in liquid silicone rubber injection molding is an important research topic. In this study, an injection mold with high energy efficiency of vulcanization for the liquid silicone rubber injection molding of a fisheye lens was developed and implemented. The LSR injection mold has a conformal heating channel (CHC) and conformal cooling channel (CCC) simultaneously. The function of CHC is to enhance the curing rate of a fisheye lens in the LSR injection molding to meet the requirements of sustainable manufacturing. The curing rates of a fisheye lens were numerically examined using the Moldex3D molding simulation software. It was found that the curing rate of the fisheye optical lens cured by injection mold with CHC was better than that of the injection mold with a conventional heating channel. The curing efficiency could be increased by about 19.12% when the heating oil temperature of 180 °C was used to cure the fisheye optical lens. The simulation results showed that the equation y = −0.0026x3 + 1.3483x2 − 232.11x + 13,770 was the most suitable equation for predicting the curing time (y) through the heating oil temperature (x). It was found that the trend of the experimental results was consistent with the simulation results. In addition, the equation y = −0.0656x2 + 1.5827x − 0.894 with the correlation coefficient of 0.9974 was the most suitable equation for predicting the volumetric shrinkage of the fisheye optical lens (y) through the heating oil temperature (x). The volume shrinkage of the fisheye optical lens cured by injection mold with CHC was very similar to that of the injection mold with a conventional heating channel. The maximum volume shrinkage of the fisheye optical lens cured at 180 °C was about 8.5%.

Various sensing materials have been demonstrated to increase the precision of sensing technology. Nevertheless, this complicates the fabrication process for materials integration to obtain devices that can simultaneously accommodate various gas detectors, like electronic nose. The study here focuses on exploring the sensing response of different functionalization of specific sensing materials to provide an alternative way to achieve selective response to multiple gases. Triethoxysilylpropyl succinic anhydride silane (TESPSA) was introduced on 2D material MXene‐Ti3C2Tx to form carboxylic acid terminated MXene (COOH‐Ti3C2Tx) and alternately coated with polyaniline (COOH‐Ti3C2Tx/PANI). This modification doubled up the gas binding sites and improved the binding strength of the Ti3C2Tx surface to NH3 gas molecules. The 5CC‐COOH‐Ti3C2Tx/PANI sensor prepared from five coating cycles showed the highest sensitivity (214.70 %) with fast gas response rate at 80 ppm NH3 (1.75 % s‐1). Therefore, the different signal responses from specific functionalization of the same sensing material functionalization will allow the possible sensor array fabrication to achieve fingerprint‐like sensing map recognition in the presence of mixed gases. With increasing applications of sensors for daily activity monitoring, it is important to have a high‐sensitivity sensor. The study demonstrates significant sensing response enhancement by introducing surface functionalization onto MXene sensing materials. The obtained P‐type response of COOH‐Ti3C2Tx/PANI sensor exhibits a higher and table response to NH3 than pristine MXene at room temperature with different humidity conditions.

Because of its excellent machining characteristics suited for fabricating complex and hollow three-dimensional components, additive-manufactured selective laser melting (SLM) technology has been increasingly applied in the production of medical implants. In this study, SLM combined with Ti–6Al–4 V powder was used to produce titanium alloy wires and vascular stents; various laser processing parameters were employed (laser average power and exposure time). A line-shaped CO 2 laser postannealing treatment was used to improve the ductility of the Ti–6Al–4 V wires and stents. A universal testing system and a field-emission scanning electron microscope were used to compare the tensile strengths of the Ti–6Al–4 V wires, the compressive strength of the vascular stents, and the microstructural properties under various SLM parameters. The experimental results revealed the Ti–6Al–4 V wires fabricated using a laser power and exposure time of 100 W and 70 μs, respectively, to have the highest tensile strength (489.09 ± 15.27 MPa). Microtensile tests showed that the strain of the Ti–6Al–4 V wires annealed with the optimal laser power of 5 W increased from 1.18 ± 0.07 to 1.5 ± 0.41%. The compressive strength of the horizontal (S-2) structured stents before and after laser annealing was significantly higher than that of the circular arc (S-1) structured stents at both time points. The compressive strength of laser-annealed S-1 and S-2 structured stents was greater than that of unannealed stents. Compared with the unannealed stents, the compressive strength of the 5 W laser-annealed S-1 and S-2 structured stents was 58.9% and 124.4% higher, and the compression of S-1 and S-2 was 11.5% and 13.5% higher, respectively.

This study investigated the relationship of the joining strength between interfacial microstructures and the hygrothermal aging characteristics of CFRP and Ti-6Al-4V (Ti-64). Interlaced micropatterns of interweaved strips and seamless structures were fabricated on CFRP and Ti-64 plates using fiber lasers. When the laser power and scan speed were set at 27.8 W and 100 mm/s, the Ti-64 and CFRP plates, which had the lowest WCA values of 49.5 ± 1.2° and 16.6 ± 2.8°, were used for the processed interlaced micropatterns, respectively. Before the aging test, the shear force of single-bonded Ti-64/CFRP specimens with unpatterned, interweaved strips, and seamless structures was 2580.5 ± 150.5 N, 4009 ± 90.1 N, 3773.6 ± 120.8 N, respectively. After the aging test for 30 days, the shear force of the Ti-64/CFRP specimens with unpatterned, interweaved strips, and seamless structures was 2408.8 ± 65.3 N, 3880.4 ± 160 N, 3340.5 ± 96.7 N, respectively. The key factor in enhancing the tensile strength was the mechanical interlocking at the interface around the bonded area. Therefore, the laser-ablated interweaved strips were remarkably capable of enhancing the joining strength of heterogeneous materials and resisting severe environmental changes.

In this study, a radio-frequency plasma-assisted chemical beam epitaxy (RF-PACBE) system with low growing temperatures was used to grow high-quality indium nitride (InN) thin films. The prepared InN thin films were annealed through a line-shaped CO 2 laser beam irradiation in an atmospheric environment at room temperature. The structural and electrical properties of InN thin films annealed with different CO 2 laser annealing parameters were measured and analyzed. The crystalline grains turned into large and granular morphologies after the InN thin films were annealed under various feeding speeds of a motorized X -axis positioning stage. According to the measured XRD patterns and rocking curves, the InN (0 0 2) peak intensities of laser-annealed thin films were higher than those of as-grown InN thin films. All surface roughnesses and sheet resistances of laser-annealed InN thin films were higher and less than those of as-grown InN thin films. At the set feeding speed of 7.5 mm/s, the laser-annealed InN thin film had the largest grain size of 69.4 nm and the lowest sheet resistance of 20.21 ± 0.27 Ω/sq. The experimental results revealed that the proper annealing conditions could decrease grain boundaries and release internal stresses to enhance the electrical properties through adjusting feeding speeds.

This study investigates the development of a rapid wax injection tooling with enhanced heat dissipation performance using aluminum-filled epoxy resin molds and cooling channel roughening technology. Experimental evaluations were conducted on cooling channels with eleven surface roughness variations, revealing that a maximum roughness of 71.9 µm achieved an 81.48% improvement in cooling efficiency compared to smooth channels. The optimal coolant discharge rate was determined to be 2 L/min. The heat dissipation time for wax patterns was significantly reduced, enabling a cooling time reduction of approximately 12 s per product. For a production scale of 100,000 units, this equates to a time savings of about 13 days. Empirical equations were established for estimating heat dissipation time and pressure drop, with a high coefficient of determination. This research provides a valuable contribution to the mold and dies manufacturing industry, offering practical solutions for sustainable and efficient production processes.

Polyetheretherketone (PEEK) is a promising biomaterial due to its excellent mechanical properties. Most PPEK manufacturing methods include additive manufacturing, injection molding, grinding, pulse laser drilling, or incremental sheet forming. Rotary friction welding (RFW) is a promising bonding technique in many industries. However, very few studies have focused on the RFW of PEEK. Conventionally, the number of revolutions is fixed during the welding process. Remarkably, the rotary friction welding of PEEK polymer rods using an innovative variable rotational speed is investigated in this study. The average bending strength of the welded part using a three-stage transformation rotational speed was enhanced by about 140% compared with a rotational speed of 1000 rpm. The advantage of computer numerical controlled RFW of PEEK using variable rotational speed is a reduced cycle time of RFW. A reduction in cycle time of about 6% can be obtained using the proposed RFW with a three-stage transformation rotational speed. The innovative approach provides low environmental pollution and high energy efficiency and complies with sustainable development goals.

Polylactic acid (PLA) stands out as a biomaterial with immense potential, primarily owing to its innate biodegradability. Conventional methods for manufacturing PLA encompass injection molding or additive manufacturing (AM). Yet, the fabrication of sizable medical devices often necessitates fragmenting them into multiple components for printing, subsequently requiring reassembly to accommodate the constraints posed by the dimensions of the AM platform. Typically, laboratories resort to employing nuts and bolts for the assembly of printed components into expansive medical devices. Nonetheless, this conventional approach of jointing is susceptible to the inherent risk of bolts and nuts loosening or dislodging amid the reciprocating movements inherent to sizable medical apparatus. Hence, investigation into the joining techniques for integrating printed components into expansive medical devices has emerged as a critical focal point within the realm of research. The main objective is to enhance the joint strength of PLA polymer rods using rotary friction welding (RFW). The mean bending strength of welded components, fabricated under seven distinct rotational speeds, surpasses that of the underlying PLA substrate material. The average bending strength improvement rate of welding parts fabricated by RFW with three-stage transformation to 4000 rpm is about 41.94% compared with the average bending strength of PLA base material. The average surface hardness of the weld interface is about 1.25 to 3.80% higher than the average surface hardness of the PLA base material. The average surface hardness of the weld interface performed by RFW with variable rotational speed is higher than the average surface hardness of the weld interface performed at a fixed rotating friction speed. The temperature rise rate and maximum temperature recorded during RFW in the X-axis of the CNC turning machine at the outer edge of the welding part surpassed those observed in the internal temperature of the welding part. Remarkably, the proposed method in this study complies with the Sustainable Development Goals due to its high energy efficiency and low environmental pollution.

This study aims to investigate the electrochemical reduction effects on graphene oxide (GO) powders with various bias voltages and treatment times. Phosphate-buffered saline solution was used as the electrolyte in the electrochemical reduction process. The experimental results showed that the GO powders were reduced to produce the best reduced GO (rGO) powders as using a bias of −17.5 V for 2 h. After the analysis of Raman spectra for GO and rGO powders, the intensity ratios of the D and G bands increased from 0.85 to 1.08, respectively. The carbon to oxygen ratios increased from 0.4 to 1.79 measured by an X-ray photoelectron spectroscopy. Moreover, the electrical conductivity obviously increased from 7.92 × 10 −4 to 4.16 × 10 −1  S/cm. Fourier transform infrared spectra revealed the disappearance of oxygen-containing functional groups in rGO powders. According to the cyclic voltammetry analysis, the specific capacitance of the rGO powders could reach 183 F/g at the scan rate of 100 mV/S in 1 M KCl electrolyte solution. This specific capacitance value was 16 times higher than that obtained with the GO powders. The results indicated that the produced high-quality rGO powders could be used for high-performance supercapacitors.