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The purpose of this paper is to form good cutting qualities in glass-epoxy material for opening flexible areas of rigid-flex printed circuit boards (PCB) by ultraviolet (UV) laser cutting.

The cut width and cut depth of glass-epoxy materials were both observed to evaluate their cutting qualities. The heat affected zone (HAZ) of the glass-epoxy material was also investigated after UV laser cutting. The relationships between the cut width and the parameters of various factors were analyzed using an orthogonal experimental design.

The cut width of the glass-epoxy material gradually increased with the increment of the laser power and Z-axis height, while cutting speed and laser frequency had less effect on the cut width. Optimal parameters of the UV laser process for cutting glass-epoxy material were obtained and included a laser power of 6W, a cutting speed of 170 mm/s, a laser frequency of 50 kHz and a Z-axis height of 0.6 mm, resulting in an average cut width of 25 μm and small HAZ.

Flexible areas of rigid-flex PCBs are in good agreement with the cutting qualities of the UV laser. The use of a UV laser process could have important potential for cutting glass-epoxy materials used in the PCB industry.

The purpose of this study is to obtain strong materials with multiwall carbon nanotubes (MWCNTs) doped and investigate laser cut of MWCNTs also find the effect of the laser cutting parameters on composite materials.

The laminated composite plates were manufactured by using a vacuum infusion process. The mechanical properties of the composite materials produced were determined according to American Society for Testing and Materials (ASTM) D3039M, ASTM D3171, ASTM D 792 and ASTM D2583. A 130 Watts carbondioxide (CO₂) laser cutting machine was used for drilling the two different composite plates with a thickness of 1.6–1.5 mm. Three variables were considered as process parameters including laser power (in three levels of 84.50, 104.00 and 127.40 W), cutting speed (in three levels of 4, 6, 8 mm/s) and 14 mm fixed focal position.

The fibers could not be cut due to insufficient melting in the experiments performed using 84.50 and 104.00 W laser power but the cutting was successfully completed when the laser power was 127.40 W. However, as the cutting speed increased, the contact time of the laser beam with the material decreased, so the kerf decreased, but the increased laser power created a thermal effect, causing an increase in hardness around the cutting surface. This increase was lower in MWCNTs doped composites compared to pure composites. It has been found that the addition of nanoparticles to layered glass fiber composite materials played an effective role in the strength of the material and affected the CO₂ laser cutting quality.

This study is a unique study in which the CO₂ laser cutting method of MWCNT-doped composite materials was investigated and the machinability without cutting errors, such as delamination, splitting, distortion and burring using the most suitable laser cutting parameters was revealed.

The purpose of this paper is to propose an new online path planning method for porcine belly cutting. With the proliferation in demand for the automatic systems of pork production, the development of efficient and robust meat cutting algorithms are hot issues. The uncertain and dynamic nature of the online porcine belly cutting imposes a challenge for the robot to identify and cut efficiently and accurately. Based on the above challenges, an online porcine belly cutting method using 3D laser point cloud is proposed.

The robotic cutting system is composed of an industrial robotic manipulator, customized tools, a laser sensor and a PC.

Analysis of experimental results shows that by comparing with machine vision, laser sensor-based robot cutting has more advantages, and it can handle different carcass sizes.

An image pyramid method is used for dimensionality reduction of the 3D laser point cloud. From a detailed analysis of the outward and inward cutting errors, the outward cutting error is the limiting condition for reducing the segments by segmentation algorithm.

The purpose of this paper is to demonstrate the use of selective laser melting for producing single and double chamber laser cutting nozzles. The main aim is to assess a whole production chain composed of an additive manufacturing (AM) and consecutive finishing processes together. Beyond the metrological and flow-related characterization of the produced nozzles, functional analysis on the use of the produced nozzles are carried out through laser cutting experiments.

SLM experiments were carried out to determine the correct compensation factor to achieve a desired nozzle diameter on steel with known processibility by SLM and using standard nozzle geometries for comparative purposes. The produced nozzles are finished through electrochemical machining (ECM) and abrasive flow machining (AFM). The performance of nozzles produced via additive manufacturing (AM) are compared to conventional ones on an industrial laser cutting system through cutting experiments with a 6 kW fibre laser. The produced nozzles are characterized in terms of pressure drop and flow dynamics through Schlieren imaging.

The manufacturing chain was regulated to achieve 1 mm diameter nozzles after consecutive post processing. The average surface roughness could be lowered by approximately 80 per cent. The SLM produced single chamber nozzles would perform similarly to conventional nozzles during the laser cutting of 1 mm mild steel with nitrogen. The double chamber nozzles could provide complete cuts with oxygen on 5 mm-thick mild steel only after post-processing. Post-processing operations proved to decrease the pressure drop of the nozzles. Schlieren images showed jet constriction at the nozzle outlet on the as-built nozzles.

In this work, the use of an additive manufacturing process is assessed together with suitable finishing and functional analysis of the related application to provide a complete production and evaluation chain. The results show how the finishing processes should be allocated in an AM-based production chain in a broader vision. In particular, the results confirm the functionality for designing more complex nozzle geometries for laser cutting, exploiting the flexibility of SLM process.

The current state in the application of lasers for cutting and welding is reviewed. Most cutting operations are performed on specifically developed laser machine tools such as the Trumpf Lasercell and its application in the development of trim shapes and low volume panel production at a sub‐contract toolmaker is described. Robots are mainly used with lasers for welding, particularly of vehicle body components where laser welds are found to be advantageous in reducing material weight and improving body strength. One example is the production of differing thickness panels and a robotic installation for producing car door inners is described. The benefits of the new generation of Nd:YAG power lasers are listed, including the ability to transmit the laser beam via fibre optic cables. This is particularly advantageous when robots are used to manipulate the “torch” and a new robot cell from Trumpf is described. Finally, the role of gases in laser processing is discussed.

Looks at the various applications of the CO₂ gas laser in industrial material processing. Describes how the CO₂ laser beam interacts with particular materials and highlights the laser system configuration, system characteristics and attributes. Details CO₂ laser cutting, welding and surface modification and briefly touches on some emerging aerospace application areas.

Laser cutting of sheet metal in both the flat and pressed form is a well‐established technique which has been used for many years. The limitations of this process are a relatively slow speed of operation and the high capital and running costs of operating lasers. The quality of edge finish and dangers of working with lasers are additional disadvantages of the technology. Contour Cutting Technology Limited have now developed a multi‐axis plasma cutting system which produces a high‐quality finish at speeds three or four times the speed of lasers, and at around 40 per cent of the capital cost of a comparable laser system. Material from 0.8mm up to about 6mm can be successfully cut with a good quality edge finish.

This paper focuses on some of the presentations given at a technical workshop on “Laser processing of polymer‐based materials”, organised by Association of Industrial Laser Users. Applications in cutting and welding are discussed and specifically how different combinations of polymer materials and laser types produce different results. Applications are described that include pre‐weakening of car trims for integrated airbags and “on the fly” scribing of web materials used in packaging. In several of these applications, robots play an important role in manipulating the laser beam.

The problems of pattern cutting as applied to flexible elastic mesh fabrics (lace) are described within the context of the total manufacturing process. While the design and knitting stages of lace manufacture are highly computerised, providing associated benefits, the cutting room operates with conventional, slow, labour intensive machinery, leading to substantial processing bottlenecks and dependent costs. A new system is presented which uses machine vision to determine the required cutting path on the lace fabric in real‐time via sophisticated, yet high speed, image processing algorithms. The determined cutting path data are used to direct a high speed CO₂ laser beam to the correct cutting point with beam velocities of typically 6 m/sec. Simultaneous dual edge cutting is now possible using this new system, leading to lace throughput being increased by a factor of ten typically, with the possibility of processing more sophisticated designs and achieving higher cut edge quality.

The purpose of this study is, to compare laser-based additive manufacturing and subtractive methods. Laser-based manufacturing is a widely used, noncontact, advanced manufacturing technique, which can be applied to a very wide range of materials, with particular emphasis on metals. In this paper, the governing principles of both laser-based subtractive of metals (LB-SM) and laser-based powder bed fusion (LB-PBF) of metallic materials are discussed and evaluated in terms of performance and capabilities. Using the principles of both laser-based methods, some new potential hybrid additive manufacturing options are discussed.

Production characteristics, such as surface quality, dimensional accuracy, material range, mechanical properties and applications, are reviewed and discussed. The process parameters for both LB-PBF and LB-SM were identified, and different factors that caused defects in both processes are explored. Advantages, disadvantages and limitations are explained and analyzed to shed light on the process selection for both additive and subtractive processes.

The performance of subtractive and additive processes is highly related to the material properties, such as diffusivity, reflectivity, thermal conductivity as well as laser parameters. LB-PBF has more influential factors affecting the quality of produced parts and is a more complex process. Both LB-SM and LB-PBF are flexible manufacturing methods that can be applied to a wide range of materials; however, they both suffer from low energy efficiency and production rate. These may be useful when producing highly innovative parts detailed, hollow products, such as medical implants.

This paper reviews the literature for both LB-PBF and LB-SM; nevertheless, the main contributions of this paper are twofold. To the best of the authors’ knowledge, this paper is one of the first to discuss the effect of the production process (both additive and subtractive) on the quality of the produced components. Also, some options for the hybrid capability of both LB-PBF and LB-SM are suggested to produce complex components with the desired macro- and microscale features.