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Laser forming is a highly flexible and iterative contactless thermomechanical forming process that utilises a defocused laser beam to induce material shortening and bending. There is a high potential for the use of laser forming in rapid prototyping, small and unique batch production; however, to achieve that potential a certain level of automation is required. The presented work seeks to address this need of automation by proposing an end-to-end sheet-metal manufacturing system utilising laser forming and cutting, where the input for the system is a 3D CAD model and the output is a manufactured product. The contribution of the presented work is interconnected laser forming and cutting framework. The presented framework consists of subsystems for automatic extraction of geometrical information from a CAD model, process planning and generation of manufacturing information, scheduling of tasks and a feedback control loop for laser forming. The framework is experimentally validated and has shown consistent forming and cutting behaviour on two types of parts with variation in cutting features, bend angle and lengths of the bend's free edge. [ABSTRACT FROM AUTHOR]

Axonal degeneration is a key component of neurodegenerative diseases such as Huntington's disease (HD), Alzheimer's disease, and amyotrophic lateral sclerosis. Nicotinamide, an NAD+ precursor, has long since been implicated in axonal protection and reduction of degeneration. However, studies on nicotinamide (NAm) supplementation in humans indicate that NAm has no protective effect. Sterile alpha and toll/interleukin receptor motif-containing protein 1 (SARM1) regulates several cell responses to axonal damage and has been implicated in promoting neuronal degeneration. SARM1 inhibition seems to result in protection from neuronal degeneration while hydrogen peroxide has been implicated in oxidative stress and axonal degeneration. The effects of laser-induced axonal damage in wild-type and HD dorsal root ganglion cells treated with NAm, hydrogen peroxide (H2 O2 ), and SARM1 inhibitor DSRM-3716 were investigated and the cell body width, axon width, axonal strength, and axon shrinkage post laser-induced injury were measured.

Nitinol is a commonly used alloy for manufacturing medical devices (i.e., stents). This study examines the process chain for manufacturing nitinol stents, focusing on the effects of laser cutting, heat treatment, and electropolishing processes on the stent's final surface roughness, strut thickness, weight, and recoil. The laser cutting's experimental results showed an optimal surface roughness (Ra) under 1.20 μm at 65% and 95% spot overlap, corresponding to feed rates of 300 mm/min and 749 mm/min, respectively. Heat treatment experiments on expanded stent samples revealed the lowest recoil of 0.78 mm achieved at 550°C for 720 s for 0.2 mm strut thickness. Electropolishing using 18V for 20 s provided the greatest reduction in surface roughness (Ra and Rz), along with a decrease in the weight and wall thickness. The results highlight the importance of optimizing process parameters to obtain desired surface quality, shape setting, and dimensional characteristics for functional nitinol stents. The research provides insights into enhancing the manufacturing of self-expanding nitinol stents for improved clinical outcomes. [ABSTRACT FROM AUTHOR]

The growing use of titanium alloys has led to the gradual replacement of traditional processing methods by laser cutting technology, making it the preferred method for processing titanium alloy plates due to its high efficiency, precision, and adaptability. In this review, the characteristics of laser cutting technology and its application in titanium alloy plate processing are summarized, outlining several aspects of the cutting process, microstructure, and mechanical properties of the material after cutting, along with simulation predictions. Previous research categorized laser-cutting input parameters into beam parameters and process parameters, with the commonly used parameters being the laser power, cutting speed, and gas pressure. Various parameter combinations can achieve different cutting qualities, and seven indices can be used to evaluate the cutting process, with the surface roughness and slit width serving as the most common indices. Different auxiliary gases have shown a significant impact on the laser cutting quality, with commonly used gases consisting of nitrogen, argon, and air. Argon-assisted cutting generally results in better surface quality. Due to the rapid temperature change, the titanium alloy microstructure will undergo a non-diffusive martensitic phase transformation during laser cutting, producing a heat-affected zone. Experimental studies and simulations of the mechanical properties have shown that the occurrence of a martensitic phase transformation increases the hardness and residual tensile stress of the material, which reduces the fatigue strength and static tensile properties. In addition, studies have found that the more streaks appear on the cut surface, the lower the fatigue strength is, with fatigue cracks arising from the stripes. Hence, the established analytical solution model and three-dimensional finite element model can effectively predict the temperature distribution and residual stress during the cutting process. This can provide a better understanding of the high residual stress characteristics of the cutting edge and the stripe formation mechanism, allowing researchers to better explore the mechanism of laser cutting. [ABSTRACT FROM AUTHOR]

Keyhole laser-based processes have been adopted widely due to the high-quality welds and cuts that they produce and the accurately controlled dimensions of the end part. Fast-running simulation tools are required in order to estimate the dependence of process outputs, efficiency, and stability on the process variables. This work presents a fast-running simulation tool for keyhole laser-based processes with inert or no assisting gas that takes into account the effect of laser beam defocusing and the alteration of the effective reflectivity of the material due to the keyhole cavity. The model is built upgrading a successful model for the thermal phenomena based on finite differences and the enthalpy method. The presented model is compared to experimental results for the laser cutting process with both CO 2 and fiber laser sources and inert assisting gas. The model accurately predicts cutting depth and kerf, heat-affected zone width, and the dependence of the cutting depth on the position of the focal plane. The model manages to achieve reduced computational time enabling its utilization in process digital twins. [ABSTRACT FROM AUTHOR]

Fiber batteries are essential for the realization of high‐performance wearable and textile electronics with the desirable features of conventional textiles, including breathability, stretchability, and washability. However, the development of fiber batteries is limited by scalability and performance since most reported fabrication techniques are not compatible with standard battery manufacturing. This work presents a novel method for the scalable fabrication of fiber batteries with a stacked design analogous to that of conventional pouch cells using layer lamination and laser machining. To accomplish this, several poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVDF‐HFP) separators are developed, enabling lamination between conventional battery electrodes using a heated rolling press. The laminated strips are subsequently laser cut to form fibers with widths as narrow as 650–700 µm. These prototypes are successfully cycled in pouch cells and capillary tubes, delivering very high linear energies up to 0.61 mWh cm−1. Custom equipment is designed to demonstrate scalable fiber battery fabrication processing in a roll‐to‐roll fashion. This work marks a paradigm shift in fiber battery research by demonstrating substantial benefits over all previous approaches including optimal active material utilization, low inactive material content, scalability, and compatibility with equipment already used widely in the battery industry. [ABSTRACT FROM AUTHOR]

In connection with the need to obtain a properly made and cut material and the appearance of the surface layer, new manufacturing technologies were used for tests, namely the laser cutting technology. This article describes the laboratory stand built for the purpose of research, as well as the possibility of using laser cutting on several sample materials (polymer films), together with an indication of the results obtained. The idea was to elaborate on the cutting technology that will be proper for manufacturing the desired type of spacers for ion-exchange membranes separating while maintaining the required level of product quality and chemical purity. The latter criterion was the basic one, due to the scope of use of the manufactured elements. This article also describes the problem encountered during the construction of the stand or during the research. The last part of this article describes the further steps of the research that will be carried out in the future along with a discussion and summary of the research performed. It is important from the point of view of the development of production technology, but also because of the characteristics of materials for the production of surface layers and coatings resistant to mechanical or thermal wear used in industry. The introduction of innovative solutions is also aimed at studying the improvement of the economics of the production of materials that are significant, in particular, for small- and medium-sized enterprises. [ABSTRACT FROM AUTHOR]

The fabrication of plasmonic 3D microstructures is still a challenge. In this study, the fabrication of gold‐nanoparticle (Au‐NP)‐filled acrylate‐based micron‐scale cuboids forming plasmonic 3D particles is investigated. UV curable acrylate is mixed with HAuCl4 and spin‐coated onto a fused silica wafer. UV light and heat treatment of the layer result in polymerization of the acrylate and formation of Au‐NPs with a plasmonic resonance ranging from 535 to 550 nm. The plasmonic resonance wavelength decreases slightly with increasing UV dose. The resonance wavelength can be shifted by a subsequent annealing process. The decreasing resonance wavelength with increasing annealing temperature is discussed as a result of the increasing Au‐NPs. The size and the distribution of the resulting gold particles in the acrylate matrix is investigated by transmission electron microscopy. The Au‐NPs‐filled acrylate layer is laser structured using a UV‐femtosecond laser, which allows the fabrication of adjustable micro‐cuboids with edge lengths down to 15 μm. The laser‐cut micro‐cuboids are transferred into isopropanol and the plasmonic properties of the structures in the liquid are successfully demonstrated. The presented concept allows easy and large‐scale fabrication of plasmonic microstructures with independently adjustable plasmonic properties and microstructural size and shape. [ABSTRACT FROM AUTHOR]

In this study, the effects of laser cutting on the fatigue properties of carbon fibre-reinforced polymers are investigated. For this purpose, unidirectional carbon fibre-reinforced epoxy laminate is cut by laser. The material to be cut evaporates directly in the laser beam and the laser beam can produce thermally induced damage, which is referred to as heat-affected zones. Specimens are cut with two different parameters (varying cutting velocity and break time between passes) to widths up to 15 mm for investigation of the heat-affected zones effects on fatigue behaviour. Prior to fatigue tests microstructure is evaluated using light and scanning electron microscopy with regard to cutting geometry and heat-affected zones. Fatigue tests are performed using multiple amplitude tests with a stress ratio of 0.1, instrumented with a video extensometer system and thermocouples for strain and temperature measurements to determine the influence on mechanical properties and evaluate the sensitivity of the used testing method and measurement instrumentation for this use case. Lower cutting velocities and break time passes lead to a larger edge angle and thus in different specimen widths on front (laser inlet) and bottom (laser outlet) of the carbon fibre-reinforced epoxy laminate. Therefore, the resulting true geometry was considered using statistical approaches to eliminate possible cross-sectional errors regarding mechanical stress application. The results show that the specimen widths and process parameters impact the fatigue properties, highlighting the importance of knowledge about heat induction and the detection of inflicted laminate damage. [ABSTRACT FROM AUTHOR]

Abstract—The structural features and microhardness in the zone adjacent to the edges of the cut during laser cutting of gear blanks from a sheet of 40Kh steel 6 mm thick were studied. The possibility of combining laser cutting with surface hardening is shown. On average, the hardened surface layer in different sections of the cut has a thickness on the order of 150–250 μm with a maximum hardness approximately equivalent to 46–58 HRC, which is quite comparable to the hardening of 40Kh steel with most surface treatments. [ABSTRACT FROM AUTHOR]

Robotic systems equipped with high-power laser sources are often employed for the production of battery packs for the electric mobility sector. Considering the strive toward a circular manufacturing economy, there is great interest in the possibility of reconfiguring such equipment for dismantling operations. The present study explores the hybrid use of a robotized fiber laser welding system, adapting its scope from joining of battery casings toward the separation of the same thin Al sheets, enabling the recycling of the internal cells of the battery pack. Process feasibility is assessed by tailoring the beam size as well as exploiting dynamic beam oscillation to perform the separation process. Dynamic beam oscillation allows us to obtain a smaller kerf width and greater process stability with respect to linear trajectories with larger beam sizes. The damage to underlying cells of the separation region was also assessed on different materials (Al, Ni-plated steel, and Cu). Greater surface modifications and higher peak temperatures (in excess of 800 °C) were recorded when employing dynamic beam oscillation with respect to linear trajectories. This research demonstrates a pathway for reutilization of the existing technological systems for a circular and sustainable production chain in the e-mobility sector. [ABSTRACT FROM AUTHOR]

Introduction: Self-coalescing microfluidic devices represent an exciting opportunity for leveraging viscous dominated flow phenomena to reconstitute a series of reagents with a single sample infusion. In a self-coalescing microfluidic device, spatially separated dried reagents are reconstituted using a single infusion. Due to the unique device geometry, the reagents remain spatially separated after infusion. As such, self-coalescing microfluidic devices have the potential to simplify point-of-care testing by simultaneously performing multiple colorimetric tests in one device. The current versions of these devices use standard, more costly microfabrication processes and are too small to be easily read by eye. Methods: Here, we created a low cost and scaled up version of a self-coalescing microfluidic device by using laser-cut-roll-based silicone tape. In addition to eliminating the need for cleanrooms, our approach simplifies the integration of assay reagents since they can be spotted onto a coverslip and covered with the tape microfluidic device. We empirically optimized our device, finding that flow rate significantly influenced the formation of self-coalescence as well as proper reagent reconstitution. Results and Discussion: When flow rates were too slow or fast, reagents would streak, leading to inadvertent mixing between different spatial locations. Our studies further revealed that geometry had a stronger influence on device operation in low-flow conditions. Our final optimized device exhibited a 100% success rate, demonstrated through self-coalescence with no reagent streaking at 100 μL/min, which enabled the isotropic diffusion of reagents. Furthermore, the spots are spatially separated and large enough to be visualized by the naked eye and captured by a smartphone camera for downstream analysis. Taken together, our innovative device leverages the advantages of sticker microfluidics and low-cost manufacturing methods to offer standalone functionality. This approach has the potential to significantly impact point-ofcare diagnostics, particularly in resource-limited regions. By enabling multiplexed diagnostic assays through our novel technology, we aim to provide accessible and affordable healthcare solutions. [ABSTRACT FROM AUTHOR]

This study investigates the effects of a water-guided laser on the cutting performance of AISI 1020 steel sheets of various thicknesses by comparing the results with respect to a conventional laser. For this purpose, a novel nozzle design has been devised enabling the delivery of laser beams to the workpiece conventionally as well as through water guidance. Diverging from prior literature, a fiber laser is used with a high wavelength and a laser power output of 1 kW. Experiments are conducted on steel sheets with thicknesses ranging from 1.5 mm to 3 mm using three different cutting speeds and laser power levels. Analysis focuses on assessing surface roughness, burr formation and heat effects on the cut surfaces for both conventional and waterjet-guided cutting. Surface roughness is evaluated by using a 3D profilometer and cut surfaces are examined through SEM imaging. The results showed that the waterjet-guided laser system greatly reduced surface roughness and minimized problems associated with traditional laser cutting such as kerf, dross adherence and thermal damage. The study revealed that cutting speed had a greater effect on surface roughness reduction than laser power, with the most noticeable differences occurring in thinner sheets. Furthermore, the investigation suggests that the waterjet-guided laser cutting system demonstrates superior performance relative to conventional methods, particularly in surface quality. [ABSTRACT FROM AUTHOR]

Laser beam cutting (LBC) is widely accepted method for creating the complex geometries in difficult to cut sheetmetal with close tolerances and high precision. In this study, the curved profiles have been cut in Ni-based superalloy (Inconel718) thin sheet using pulsed Nd-YAG laser. The performance of the process in terms of top kerf deviation (TKD) and kerf taper (KT) has been analyzed by employing the response surface modelling (RSM) and neural network modelling (NNM) approaches. Experiments have been conducted using the Box-Behnken design (BBD) by considering the four laser cutting parameters namely lamp current, pulse width, pulse frequency and cutting speed. The experimental results have been used further to develop the regression and neural network models. Subsequently, predicted results from both the models have been compared with the actual experimental results. On comparison, the prediction error for RSM were found as 14.06% and 14.18%, while for NNM were 12.23% and 6.80% for TKD and KT, respectively. Hence, both the models confirmed strong ability to match the responses. NN model exhibited superior predictive power. [ABSTRACT FROM AUTHOR]

Among the non-traditional manufacturing processes, electro-thermal based processes are used to machine the difficult to cut materials. Among thermal based unconventional machining processes, laser machining and plasma arc cutting (PAC) are most significant processes that find applications in various industries including aerospace, automotive, shipbuilding, chemical processes equipment manufacturing and fabrication. In this manuscript, the parametric optimization of PAC is extensively reviewed. Bibliometric analysis of PAC was performed using Web of science and Scopus database wherein research publications were analyzed between year of 1961 to 2023. It was observed from the analysis that minimization of energy consumption in thermal based non-conventional machining methods is not extensively studied. Therefore, literature was reviewed to discuss about energy consumption and reduction of energy requirements in laser and PAC machining. [ABSTRACT FROM AUTHOR]

As an alternative to SU-8 soft lithography, a new silicon mold process of fabricating PDMS microchannel chips was proposed. A picosecond laser is used to cut through a 550 μm thick silicon wafer and generate the original microchannel pattern with a 50 μm minimum feature size. This single-crystal silicon pattern, with the edge debris caused by laser cutting being trimmed off by a KOH solution and with the protection field oxide layer being removed by BOE afterwards, firmly resided on a glass substrate through the anodic bonding technique. Four-inch wafers with microchannel patterns as the PDMS mold cores were successfully bonded on Pyrex 7740 or Eagle XG glass substrates for the follow-up PDMS molding/demolding process. This new maskless process does not need a photolithography facility, but the laser cutting service must be provided by professional off-campus companies. One PDMS microchannel chip for particle separation was shown as an example of what can be achieved when using this new process. [ABSTRACT FROM AUTHOR]

A high-power fiber laser was used to cut AZ31B magnesium alloy. The effects of laser cutting speed, assisted air pressure, and defocus on cutting quality were studied systematically. Scanning electron microscope and ultra-depth-of-field three-dimensional microscope were used to observe the morphology of kerf and the cutting surface. The results show that the kerf width at the straight line and the kerf width at the sharp corner always keep the synchronous change law. The cutting surface can usually be divided into three areas: top area, scour area, and stripe area. The change of the area of the three regions has an important influence on the roughness value of the cutting surface. Studying the variation of roughness by studying the variation of three areas is applicable to laser cutting speed and assisted air pressure, but not to defocus. The slag height decreases from 75.87 to 46.83 μm with the increase of laser cutting speed. The slag height decreases rapidly to 52.88 μm and then increases slowly to 61.74 μm with the change of defocus. The slag height decreases rapidly from 58.37 to 24.81 μm with the increase of assisted air pressure. [ABSTRACT FROM AUTHOR]

This study investigates laser-induced damage in thin silicon (Si) wafer ablation both experimentally and numerically. A 40-W continuous-wave CO2 laser is employed as the volumetric heat source. Experiments are conducted that involve variations in the laser cutting speed from 5 to 20 mm/s and the number of passes from one to three while maintaining a constant laser power of 40 W for investigation. The measured output parameters include surface morphologies, heat-affected zone (HAZ), and kerf width. For the first time, a finite element solution based on the brittle–ductile transition (BDT) phenomenon is introduced to predict temperature-stress gradients in the laser cutting region. Johnson–Cook (J-C) plasticity, along with the introduced damage criteria, are employed to analyse the cutting characteristics. The results show that the lowest CO2 laser speed and minimal number of passes enhance Si wafer quality. Nevertheless, increasing cutting speed and the number of passes significantly intensify material ablation and oxidisation due to elevated laser heat input. Using optimal parameters, numerical analysis shows a high level of agreement with experimental findings. Transverse/longitudinal stresses correlate with temperature, while the longitudinal stress is substantially lower compared to the transverse stresses due to thermal expansion and the direction of heat transfer. Following that, computed assessments of compressive and tensile stresses are used to refine specific laser parameters and locations for experimental setup. [ABSTRACT FROM AUTHOR]

In the field of ultra-thick plate cutting, thermal cutting using high-temperature heat is used rather than mechanical cutting, and research is being conducted to increase the efficiency of cutting. In this paper, in order to improve cutting efficiency, a hybrid cutting head using both laser and gas cutting was designed, and the optimal cutting conditions were demonstrated through an experiment for cutting ultra-thick plate using the manufactured cutting head. The plate material used 100 t carbon steel, and a multi-axis hybrid method was adopted. As a result of the experiment was confirmed that the cutting speed was improved more than twice as much as when using the single cutting method, and the optimal speed condition in which sludge did not occur was derived. The maximum cutting speed was 600 mm/min, and the optimal cutting speed at which sludge did not occur was confirmed at 550 mm/min. [ABSTRACT FROM AUTHOR]

Acoustic emission (AE) technology is an effective method for monitoring the quality of carbon fiber reinforced plastic (CFRP) laser cutting. It is a challenge to decipher the formation mechanism because of the heterogeneity and anisotropy of CFRP. By analyzing the characteristics of AE signals and the images captured by the high-speed camera under different parameters, four types of AE signal sources were found: high-strength carbon fiber fractures, uniform resin ablation, photochemical fractures, and plasma plume impact. Kerf depth can be accurately identified by measuring the amplitude of the AE signal, and the experimental results verify that the error between the predicted and the experiment values is less than 0.1 mm. The laser defocusing amount, the width of the Heat-affected zone (HAZ), and the overall cutting time can be accurately determined by measuring the Root Mean Square (RMS) of the AE signal. The focus position can be adjusted before the laser cutting, decreasing the width of HAZ from 211.3 μm to 131.5 μm and the time of through-hole cutting from 245 s to 207 s. [ABSTRACT FROM AUTHOR]

In the last decade, increased availability of 3d printers and laser cutters has led to development of specialized market for producing models as souvenirs and personalized gifts. One type of such models are city scale-models. The topic of this research deals with the examination of various laser engraving and laser cutting techniques, as well as the application of 3d printing in the production of specialized city scale-models. The aim of the research is to find the most efficient way of realising this project while fulfilling the following criteria: production time, quality of the final result (need for additional processing) and total production costs. Results of this research are successfully fabricated city scale-models and a tabular overview containing data on the basis of which the best approach can be determined, in relation to given predispositions. [ABSTRACT FROM AUTHOR]

Fiber lasers, the latest laser-cutting technology, are notable for their high process efficiency, cutting precision, and high cutting quality for thin materials. However, the quality of the cut significantly decreases when machining thicker materials. For now, this is a challenge for the metalworking industry. This study investigated the effects of laser power, cutting speed, and auxiliary gas pressure on the fiber-laser cutting quality of 4 and 6 mm thick S355JR steel plates. To evaluate the influence of cutting parameters on cutting quality, surface roughness, dimensional accuracy and cut taper were measured. A microscopic analysis of the laser cuts was performed, revealing the heat-affected zone, transition zone and unaffected base-material zone. Research results show that laser cutting is a complex process, and the correct choice of cutting parameters greatly influences the cutting performance and final quality. An artificial neural network was created and trained using the results from measuring the quality characteristics to achieve optimum cutting quality. The accuracy of the optimization model was assessed by control samples, which were cut using calculated optimum parameters. The actual values of the quality characteristics only slightly differ from the predicted values, showing that the optimization model is suitable for selecting cutting parameters. [ABSTRACT FROM AUTHOR]

Here we demonstrate fast selective laser‐induced etching (SLE) process with three‐dimensional (3D) hologram optics to reduce display bezel thickness with cost effective methods. To apply fast SLE for display manufacturing, one‐side etching process should be presumed to protect display active area. We developed one‐side selective laser‐induced etching with asymmetric 3D hologram laser beam satisfying with commercial mechanical strength. Faster etch process having etch rate 10 µm/min than common SLE, 1~3 µm/min was developed. Furthermore, we achieve that bezel thickness is 100 µm shorter than wheel scribing and CNC grinding. [ABSTRACT FROM AUTHOR]

In this study, we analyzed the laser cutting characteristics of pulse transverse electrical discharge in gas at atmospheric pressure (TEA) CO2 and ultraviolet (UV) pulse laser processing in a multilayer display panels. First, the numerical calculation for was performed to confirm the thermal characteristics of each materials and optical field distribution at the interface of different material layers. Also, processing characteristics were experimentally confirmed by measuring cutting profile and adhesion characteristics of layer interface. Experimental results show that the characteristics of multi layers polymer cutting have different trend from those in a single‐layer because of the optical and thermal properties of each layer. In particular, the interface of layers had a substantial affect due to optical field distributions and thermal characteristic difference. Also, the optical absorbance of layers affect adhesion at the interface. The result suggests proper processing condition to enhance the laser ablation processing quality of multilayer display panel. In conclusion, understanding the characteristics of multilayer laser cutting processing is important for determining the optimal conditions for display panel micromachining and enhancing the quality of laser cutting for the cutting edge technology. [ABSTRACT FROM AUTHOR]

The reactors, in which underwater laser cutting is applied, are usually more than 10m high, and the inside of the reactor is filled with coolant. It is necessary to investigate underwater laser cutting by constructing a pressurized water tank that simulates a 10-meter-deep environment in consideration of the 10-meter-deep environment where underwater cutting will be performed during actual reactor dismantling. Therefore, this study aims to first examine the effect of water pressure on laser cutting in an underwater environment and then analyze the quality of the cut part according to the cutting direction and nozzle diameter. [ABSTRACT FROM AUTHOR]

The service performance of hot stamped ultra-high strength steel after die punching was evaluated in this paper through typical experiments, including tensile tests, bending tests, and hydrogen embrittlement tests, as well as characterization analysis. The tested samples were prepared through a specially designed tool by considering different die clearances, punch corner radii, and punch shapes. The results showed that the tensile properties are closely related with the selected punching parameters, while the bending properties and hydrogen embrittlement susceptibility are less sensitive to parameters. Furthermore, the laser cutting method was also involved to produce holes on hot stamped parts and compared with the punching samples. It was found that the laser cutting samples performed better in terms of tensile properties and hydrogen embrittlement susceptibility, which were due to the effects of annealing treatment during laser cutting that decreases the material hardness and brings compressive residual stress near the cutting surface, while the bending properties are insensitive to different drilling methods. [ABSTRACT FROM AUTHOR]

The main goal of these scientific studies, which are reflected in this work, is aimed at finding ways to improve quality indicators in the implementation of laser processing of tubular thin-walled blanks. The analysis of literary sources showed that the majority of scientific research is aimed at improving the process of combined gas-laser cutting of relatively thick metal plates. Compared to this, the process of interaction of a focused laser beam and a flow of compressed gas with thin-walled tubular blanks is more complicated. Because it is necessary to take into account the effect of laser radiation on the lower part of the tubular workpiece, as well as the effect of gas pressure, which can distort the geometric configuration of the medical endoprosthesis. After a thorough analysis of a priori information, a strategy of theoretical research was developed, followed by an adequacy check by obtaining experimental samples of medical endoprostheses. Namely, with the help of the Fluent 6.2 software package, the process of the propagation of the auxiliary gas jet at the outlet of the conical nozzle and its interaction with the tubular thin-walled workpiece was simulated. A method of modeling the process of spreading the jet of auxiliary gas at the outlet of the conical nozzle has been developed. Which made it possible to determine the limit values of the auxiliary gas pressure distribution along the axis of the nozzle at which deformation processes and distortion of the geometric configuration of the medical endoprosthesis occur. According to the results of the modeling of the process of the interaction of the auxiliary gas with a cylindrical thin-walled blank, an experimental batch of blanks for medical endoprostheses with a diameter of 1.6 and 4 mm with the simplest ”linear” design of the pattern and different thread lengths and a circle step equal to 0.16 mm was produced. Medical endoprostheses are widely used in medicine for the treatment of such dangerous diseases as thrombophlebitis. [ABSTRACT FROM AUTHOR]

This article considered the problem of improving the quality of the edges of parts cut by laser radiation, due to a new approach, which consists in smoothing the surface of laser cuts with a ball tool. The conducted analysis showed the prospects of improving the characteristics of the technology of laser cutting parts from sheets of different thickness when applying subsequent ball smoothing of the cut surface. The purpose of the study is a comprehensive analysis of the effect of smoothing parameters on the operational characteristics of parts obtained by this combined method. The necessary methods of assessing the roughness of the cut surfaces, the microhardness of their edges, and the residual stresses occurring in the surface layer of the cut were used to conduct the experiments. Based on the formulated hypothesis about the prospect of improving the characteristics of the cut edges during their subsequent smoothing, it was experimentally established that there is a noticeable decrease in the values of roughness parameters after smoothing the surface of laser cuts compared to their values for samples only after laser cutting. In addition, studies show that in the region of the edge of the cut, there is an increase in the microhardness of the cut surface by up to 20%. At the same time, compressive stresses appear on the edge of the cut, which ensure an increase in the operational characteristics of the parts after the proposed combined treatment. To implement the researched technology of smoothing the laser cut surface, the design of the smoothing head was proposed. As a result of the study of the proposed combined method of obtaining parts by laser cutting with subsequent smoothing of the surface of the cuts, it was confirmed that with low additional capital costs, it is possible to significantly improve the operational characteristics of the parts produced in this way. This also proves the prospects for further development of the presented combined technology, both with the use of ball smoothing and with the application of other methods of surface strengthening of laser cut edges. [ABSTRACT FROM AUTHOR]

With the megatrend of digitalization, the demand for sensors in previously difficult-to-access scenarios is increasing. Filament-shaped sensors (FSS) are ideal for this demand, especially in applications in which the monitoring of textile structures is the focus. Electrically conductive bicomponent filaments based on thermoplastic polyurethane (TPU) and doped with carbon nanotubes (CNTs) offer great potential due to their flexible mechanical properties. Through the core-conducting, bicomponent structure, the sensing material is protected from environmental factors such as surrounding conductive materials and external moisture. The insulating material, however, simultaneously complicates the contacting method in order to measure sensing changes in the conductive core. In this work, laser cutting is employed as a technology in order to expose the conductive core of the filaments. The filament is then coated with silver and mechanically crimped, providing both a conductive interface for the data acquisition device as well as a protective layer. Laser parameters (power 20–100 W and speed 5–50 mm/s) are investigated to identify the parameters with the best cutting properties for which the filaments are analyzed visually and electrically. This work provides a robust and reproducible method for contacting core-conducting TPU filaments for strain-sensing applications. This study shows that while the choice of laser parameter influences the morphology of the cut surface, its impact on the resulting linear resistivity is negligible. [ABSTRACT FROM AUTHOR]

Laser machining is a technique capable of achieving extremely precise material cutting using appropriate parameters. The research proposes a new approach for producing biodegradable hybrid composites composed of Polylactic acid (PLA), bamboo particles (BP), and montmorillonite (MMT) clay using an innovative solvent-free stir-casting technique optimised for maximum efficiency. The primary objective is to evaluate the machinability of the resultant PLA/BP/clay hybrid polymer composite in-depth, emphasising important quality characteristics such as surface roughness, kerf angle, and material removal rate. The key machining parameters under consideration are laser power, scan speed, and gas pressure. This evaluation encompassed the utilisation of Analysis of Variance (ANOVA) to comprehend the extent of impact these process parameters have on the quality characteristics. Additionally, an interactive model was developed for forecasting and enhancing the quality parameters of laser cutting using Response Surface Methodology (RSM). The Particle Swarm Optimisation (PSO) algorithm was also employed to determine the optimal values of the design parameters for machining composites. The laser power has been precisely optimised to a value of 21.40 W. A constant setting of 3 mm/s for the scan speed and 3.04 bar of gas pressure enables accurate and controlled laser machining of the hybrid polymer composite. [ABSTRACT FROM AUTHOR]

The strength–ductility mechanism of the low-carbon steels processed by laser cutting is investigated in this paper. A typical gradient-phased structure can be obtained near the laser cutting surface, which consists of a laser-remelted layer (LRL, with the microstructure of lath bainite + granular bainite) and heat-affected zone (HAZ). As the distance from the laser cutting surface increases, the content of lath martensite decreases in the HAZ, which is accompanied by a rise in the content of ferrite. Considering that the microstructures of the LRL and HAZ are completely different from the base metal (BM, ferrite + pearlite), a significant strain gradient can be inevitably generated by the remarkable microhardness differences in the gradient-phased structure. The hetero-deformation-induced strengthening and hardening will be produced, which is related to the pileups of the geometrically necessary dislocations (GNDs) that are generated to accommodate the strain gradient near interfaces. Plural phases of the HAZ can also contribute to the increment of the hetero-deformation-induced strengthening and hardening during deformation. Due to the gradient-phased structure, the low carbon steels under the process of laser cutting have a superior combination of strength and ductility as yield strength of ~487 MPa, tensile strength of ~655 MPa, and total elongation of ~32.7%. [ABSTRACT FROM AUTHOR]

The demand for easy-to-use, affordable, accessible, and reliable technology is increasing in biological, chemical, and medical research. Microfluidic devices have the potential to meet these standards by offering cost-effective, highly sensitive, and highly specific diagnostic tests with rapid performance and minimal sample volumes. Traditional microfluidic device fabrication methods, such as photolithography and soft lithography, are time-consuming and require specialized equipment and expertise, making them costly and less accessible to researchers and clinicians and limiting the applicability and potential of microfluidic devices. To address this, researchers have turned to using new low-cost materials, such as double-sided tape for microfluidic device fabrication, which offers simple and low-cost processes. The innovation of low-cost and easy-to-make microfluidic devices improves the potential for more devices to be transitioned from laboratories to commercialized products found in stores, offices, and homes. This review serves as a comprehensive summary of the growing interest in and use of double-sided tape-based microfluidic devices in the last 20 years. It discusses the advantages of using double-sided tape, the fabrication techniques used to create and bond microfluidic devices, and the limitations of this approach in certain applications. [ABSTRACT FROM AUTHOR]

This study focused on the efficacy of employing a pulsed fiber laser in the curved cutting of thin, non-oriented electrical steel sheets. Experiments were conducted in paraffinic oil by adjusting the input process parameters, including laser power, pulse frequency, cutting speed, and curvature radius. The multiple output quality metrics included kerf width, inner and outer heat-affected zones, and re-welded portions. Analyses of the Random Forest Method and Response Surface Method indicated that laser pulse frequency was the most important variable affecting the cut quality, followed by laser power, curvature radius, and cutting speed. To improve cut quality, an innovative artificial intelligence (AI) approach incorporating a deep neural network (DNN) model and a modified equilibrium optimizer (M-EO) was proposed. Initially, the DNN model established correlations between input parameters and cut quality aspects, followed by M-EO pinpointing optimal cut qualities. Such an approach successfully identified an optimal set of laser process parameters, even beyond the specified process window from the initial experiments on curved cuts, resulting in significant enhancements confirmed by validation experiments. A comparative analysis showcased the developed models' superior performance over prior studies. Notably, while the models were initially developed based on the results from curved cuts, they proved adaptable and capable of yielding comparable outcomes for straight cuts as well. [ABSTRACT FROM AUTHOR]

Copyright of Textile Industry / Tekstilna Industrija is the property of Union of Textile Engineers & Technicians of Serbia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Laser-processing technology has been widely used in the ultra-precision machining of diamond materials. It has the advantages of high precision and high efficiency, especially in the field of super-hard materials and high-precision parts manufacturing. This paper explains the fundamental principles of diamond laser processing, introduces the interaction mechanisms between various types of lasers and diamond materials, focuses on analyzing the current development status of various modes of laser processing of diamond, briefly discusses the relevant applications in diamond cutting, micro-hole forming, and micro-groove machining, etc., and finally discusses the issues, challenges, and potential future advancements of laser technology in the field of diamond processing at this point. [ABSTRACT FROM AUTHOR]

Soft robots with good deformability and adaptability have important prospects in the bionics and intelligence field. However, current research into soft robots is primarily limited to the study of actuators and ignores the integrated use of functional devices and actuators. To enrich the functions of soft robots and expand their application fields, it is necessary to integrate various functional electronic devices into soft robots to perform diverse functions during dynamic deformation. Therefore, this paper discusses methods and strategies to manufacture optical stimuli-responsive soft actuators and integrate them into functional devices for soft robots. Specifically, laser cutting allows us to fabricate an optically responsive actuator structure, e.g., the curling direction can be controlled by adjusting the direction of the cutting line. Actuators with different bending curvatures, including nonbending, can be obtained by adjusting the cutting depth, cutting width, and the spacing of the cutting line, which makes it easy to obtain a folded structure. Thus, various actuators with complex shape patterns can be obtained. In addition, we demonstrate a fabrication scheme for a worm-like soft robot integrated with functional devices (LEDs are used in this paper). The local nonbending design provides an asymmetric structure that provides driving power and avoids damage to the functional circuit caused by the large deformation during movement. The integration of drive and function provides a new path for the application of soft robots in the intelligence and bionics field. [ABSTRACT FROM AUTHOR]

Axonal degeneration is a key component of neurodegenerative diseases such as Huntington's disease (HD), Alzheimer's disease, and amyotrophic lateral sclerosis. Nicotinamide, an NAD+ precursor, has long since been implicated in axonal protection and reduction of degeneration. However, studies on nicotinamide (NAm) supplementation in humans indicate that NAm has no protective effect. Sterile alpha and toll/interleukin receptor motif‐containing protein 1 (SARM1) regulates several cell responses to axonal damage and has been implicated in promoting neuronal degeneration. SARM1 inhibition seems to result in protection from neuronal degeneration while hydrogen peroxide has been implicated in oxidative stress and axonal degeneration. The effects of laser‐induced axonal damage in wild‐type and HD dorsal root ganglion cells treated with NAm, hydrogen peroxide (H2O2), and SARM1 inhibitor DSRM‐3716 were investigated and the cell body width, axon width, axonal strength, and axon shrinkage post laser‐induced injury were measured. [ABSTRACT FROM AUTHOR]

Laser cutting is a precise, powerful, and low-cost tool for cutting different sheets of metals and polymers. The literature survey shows that the quality of cutting (surface roughness and kerf geometry) is a sophisticated parameter and conventional approaches cannot describe the quality of cutting for thin sheets of polymers very well. Statistical tools can help to interpret the effect of process variables. In this article, the laser cutting of Polymethyl methacrylate (PMMA) is experimentally investigated. The effect of process variables of laser cutting including the scanning speed, laser power, and laser beam diameter on the kerf width and surface roughness by Response Surface Methodology design investigated. The results revealed that increasing the laser power leads to increasing the surface roughness and decreasing the taper angle, while the kerf width at the top and bottom surface of the sheet decreases at first, then increases (for higher laser power than 90W). Also, increasing the scanning speed causes increasing surface roughness while the taper angle and the kerf width at the top and bottom surface increase at first, then it decrease. By increasing the laser beam diameter, the surface roughness will increase while the taper angle and the kerf width at the top and bottom surface decrease at first and then increase. The sophisticated effect of the main process variables and their interactions determines that finding the optimum condition of process parameters is hard and multi-objective optimization approaches are needed to find local minimum surface roughness and kerf geometry. [ABSTRACT FROM AUTHOR]

When designing technological processes, developers always face tasks aimed at increasing the efficiency of the laser cutting process of tubular blanks, as well as improving technological equipment. The main efforts are aimed at improving the quality indicators, in particular the roughness of the cut surface, as well as the elastic characteristics of medical endoprostheses. The analysis of scientists' research on laser processing of medical endoprostheses made it possible to determine the main priority directions of scientific research, namely the search for ways to improve experimental equipment and optimal control parameters of the technological process of laser processing of tubular thin-walled blanks. The purpose of this is to increase the elastic characteristics of the medical endoprosthesis, in particular its flexibility due to the reduction of the width of the cut, as well as the optimization of the technological process of laser cutting of the tubular thin-walled blank. On the basis of a priori information, methods and approaches were developed to improve technological equipment in order to increase the productivity and quality of manufacturing medical endoprostheses. Namely, a complex approach was developed to increase the elastic characteristics of the stent by reducing the width of the laser cut. In particular, the methods of mathematical statistics were used for the effective analysis of technological factors affecting the process of laser treatment of medical endoprostheses. Namely, mathematical models of the process of laser cutting of thin-walled tubular blanks were obtained. In this work, the optimal configuration of the experimental prototype of experimental equipment for the manufacture of medical endoprostheses (stents) was developed. Also, a technique was developed and optimization of the control parameters of the process of laser cutting of tubular blanks was carried out. The results of experimental studies showed the possibility of reducing the width of the laser cut, which made it possible to improve the elastic characteristics of the medical endoprosthesis. [ABSTRACT FROM AUTHOR]

To address the issues of workpiece distortion and excessive material melting caused by heat accumulation during laser cutting of thin-walled sheet metal components, this paper proposes a segmented optimization method for process parameters in sheet metal laser cutting considering thermal effects. The method focuses on predetermined perforation points and machining paths. Firstly, an innovative temperature prediction model T p r , t is established for the nth perforation point during the cutting process, with a prediction error of less than 10%. Secondly, using the PSO-BP-constructed prediction model for laser cutting quality features and an empirical model for processing efficiency features, a multi-objective model for quality and efficiency is generated. The NSGA II algorithm is employed to solve the objective optimization model and obtain the Pareto front. Next, based on the predicted temperature at the perforation point using the model T p r , t , the TOPSIS decision-making method is applied. Different weights for quality and efficiency are set during the cutting stages where the temperature is below the lower threshold and above the upper threshold. Various combinations of machining parameters are selected, and by switching the parameters during the cutting process, the thermal accumulation (i.e., temperature) during processing is controlled within a given range. Finally, the effectiveness of the proposed approach is verified through actual machining experiments. [ABSTRACT FROM AUTHOR]

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Self-coalescing microfluidic devices represent an exciting opportunity for leveraging viscous dominated flow phenomena to reconstitute a series of reagents with a single sample infusion. In a self-coalescing microfluidic device, spatially separated dried reagents are reconstituted using a single infusion. Due to the unique device geometry, the reagents remain spatially separated after infusion. As such, self-coalescing microfluidic devices have the potential to simplify point-of-care testing by simultaneously performing multiple colorimetric tests in one device. The current versions of these devices use standard, more costly microfabrication processes and are too small to be easily read by eye.Methods: Here, we created a low cost and scaled up version of a self-coalescing microfluidic device by using laser-cut-roll-based silicone tape. In addition to eliminating the need for cleanrooms, our approach simplifies the integration of assay reagents since they can be spotted onto a coverslip and covered with the tape microfluidic device. We empirically optimized our device, finding that flow rate significantly influenced the formation of self-coalescence as well as proper reagent reconstitution.Results and Discussion: When flow rates were too slow or fast, reagents would streak, leading to inadvertent mixing between different spatial locations. Our studies further revealed that geometry had a stronger influence on device operation in low-flow conditions. Our final optimized device exhibited a 100% success rate, demonstrated through self-coalescence with no reagent streaking at 100 μL/min, which enabled the isotropic diffusion of reagents. Furthermore, the spots are spatially separated and large enough to be visualized by the naked eye and captured by a smartphone camera for downstream analysis. Taken together, our innovative device leverages the advantages of sticker microfluidics and low-cost manufacturing methods to offer standalone functionality. This approach has the potential to significantly impact point-of-care diagnostics, particularly in resource-limited regions. By enabling multiplexed diagnostic assays through our novel technology, we aim to provide accessible and affordable healthcare solutions.