Journal articles: 'Fibre Laser'

1

McCaffer, C. J., L. Pabla, and C. Watson. "Curved adjustable fibre-optic diode laser in microscopic cholesteatoma surgery: description of use and review of the relevant literature." Journal of Laryngology & Otology 132, no. 4 (March 8, 2018): 360–63. http://dx.doi.org/10.1017/s0022215118000117.

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AbstractObjective:The use of lasers in cholesteatoma surgery is common and well accepted. The most commonly used laser fibres are straight and non-adjustable; these have several limitations. This paper describes the use of an alternative laser fibre.Method:This ‘How I Do It’ paper describes and illustrates the use of an alternative curved adjustable fibre-optic diode laser in microscopic cholesteatoma surgery.Results:The curved, adjustable laser fibre allows accurate and atraumatic disease removal when the use of a straight laser fibre may be less effective or accurate. It reduces potential damage to delicate structures without the need for extra drilling or bone removal.Conclusion:It is suggested that the curved adjustable laser fibre is superior to the traditional straight fibre for cholesteatoma surgery.

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He, Wentao, and Zhiwei Men. "Analysis on Transmission Characteristics of Stimulated Raman Scattering Based on the Multi-Sensor Signal Enhancement Technique." Scientific Programming 2022 (May 11, 2022): 1–9. http://dx.doi.org/10.1155/2022/5726718.

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In recent 20 years, fibre laser system has been developed rapidly and widely used for its high quality, high efficiency, high robustness, and compactness. However, there are still many factors (such as non-linear effect, thermal effect, and mode instability) that limit the further increase of power of fibre laser system. Stimulated Raman scattering (SRS) is one of the main limitations in the transmission process of fibre lasers. It not only reduces the output efficiency of fibre lasers, but also increases the damage risk of reverse Stokes light to the system. Recent studies have shown that SRS in low-mode fibres can lead to quasi-static mode degradation in addition to mode instability. With the introduction of multi-sensor enhancement technology in the fibre field, it becomes an effective means to popularise high-power and high-beam quality fibre lasers. Based on the multi-sensor signal enhancement technology, this paper explores the influence of this technology on the output efficiency of SRS in the mode-reducing fibre laser, which provides a new idea and method for the output efficiency and transmission analysis method of fibre laser.

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Popov, S. M., O. V. Butov, A. O. Kolosovskii, V. V. Voloshin, I. L. Vorob’ev, V. A. Isaev, D. V. Ryakhovskii, et al. "Optical fibres with an inscribed fibre Bragg grating array for sensor systems and random lasers." Quantum Electronics 51, no. 12 (December 1, 2021): 1101–6. http://dx.doi.org/10.1070/qel17659.

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Abstract We report the latest results on inscribing extended fibre Bragg grating (FBG) arrays upon fibre drawing, obtained at the Kotelnikov Institute of Radioengineering and Electronics of RAS. The properties of these structures are considered, and examples of their application in sensor systems of microwave dense wavelength multiplexing and as a basis for designing single-frequency fibre lasers are considered. The optical and laser characteristics of FBG arrays, inscribed (using 248-nm UV laser radiation) both in standard single-mode telecommunication fibres of the SMF-28 type and in erbium-doped active fibres, are investigated.

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Franczyk, Marcin, Dariusz Pysz, Filip Włodarczyk, Ireneusz Kujawa, and Ryszard Buczyński. "Yb3+ doped single-mode silica fibre laser system for high peak power applications." Photonics Letters of Poland 12, no. 4 (December 31, 2020): 118. http://dx.doi.org/10.4302/plp.v12i4.1075.

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We present ytterbium doped silica single-mode fibre components for high power and high energy laser applications. We developed in-house the fibre laser with high efficiency of 65% according to the launched power, the threshold of 1.16W and the fibre length of 20 m. We also elaborated the fibre with 20 µm in diameter core suitable for amplifying the beam generated in oscillator. We implemented made in-house endcaps to prove the utility of the fibre towards high peak power applications. Full Text: PDF ReferencesStrategies Unlimited, The Worldwide Market for Lasers: Market Review and Forecast, 2020 DirectLink J. Zhu, P. Zhou, Y. Ma, X. Xu, and Z. Liu, "Power scaling analysis of tandem-pumped Yb-doped fiber lasers and amplifiers", Opt. Express 19, 18645 (2011) CrossRef IPG Photonics, Product information, accessed: October, 2020. DirectLink J.W. Dawson, M. J. Messerly, R. J. Beach, M. Y. Shverdin, E. A. Stappaerts, A. K. Sridharan, P. H. Pax, J. E. Heebner, C. W. Siders, and C. P. J. Barty, "Analysis of the scalability of diffraction-limited fiber lasers and amplifiers to high average power", Opt. Express 16, 13240 (2008) CrossRef W. Koechner, "Solid-State Laser Engineering", Springer Series in Optical Science, Berlin 1999 CrossRef A. V. Smith, and B. T. Do, "Bulk and surface laser damage of silica by picosecond and nanosecond pulses at 1064 nm", Appl. Opt. 47, 4812 (2008), CrossRef M. N. Zervas, C. Codemard, "High Power Fiber Lasers: A Review", IEEE J. Sel. Top. Quantum Electron. 20, 1, 2014 CrossRef D.J. Richardson, J. Nilsson, and W.A. Clarkson, "High power fiber lasers: current status and future perspectives [Invited]", J. Opt. Soc. Am. B, 27, 63, 2010, CrossRef M. Li, X. Chen, A. Liu, S. Gray, J. Wang, D. T. Walton; L. A. Zenteno, "Limit of Effective Area for Single-Mode Operation in Step-Index Large Mode Area Laser Fibers", J. Lightw. Technol., 27, 3010, 2009, CrossRef J. Limpert, S. Hofer, A. Liem, H. Zellmer, A. Tunnermann., S. Knoke, and H. Voelckel, "100-W average-power, high-energy nanosecond fiber amplifier", App.Phys.B 75, 477, 2002, CrossRef

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Kutin, A. A., and M. V. Turkin. "Advanced Fiber Laser Perforation Technology for Thermoplastic Pre-Preg Material." Key Engineering Materials 496 (December 2011): 36–43. http://dx.doi.org/10.4028/www.scientific.net/kem.496.36.

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A study concerning the application of fiber laser to perforate thermoplastic pre-pregs is presented. An IPG fiber laser was used to drill arrays of holes in PEKK carbon-fiber composite pre-preg material. Perforated holes were of the order of 100μm. The effects of laser perforation process parameters including the number of pulses on the geometry of the resultant holes and the thermal damage to the matrix and fibres have been investigated. Dimensional analysis and experimental results have been used to construct the laser perforation process model. Keywords: Laser perforation; Fibre laser; Process modelling; Polymer matrix composites.

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Hennings, T., D. Hennings, and C. Lindsay. "Thrombus formation using endovenous lasers: an in vitro experiment." Phlebology: The Journal of Venous Disease 29, no. 3 (May 6, 2013): 171–78. http://dx.doi.org/10.1177/0268355512473921.

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Objectives: The purpose of these experiments was to simulate thrombus formation during endovenous laser closure by measuring coagulum formation of in vitro laser exposures in porcine blood and investigate the role of procedures and equipment in thrombus formation. Methods: Continuous wave 810, 940, 980, 1310 and 1470 nm lasers and microsecond pulsed wave 1064 nm Nd:YAG (neodymium-doped yttrium aluminium garnet), 1320 nm Nd:YAG and 2100 nm THC:YAG (thulium holmium chromium-doped yttrium aluminium garnet) lasers were tested with standard fibres with diameters of 365, 550 and 600 μm as well as two prototype modified tip fibres. Results: The results show that pulsed lasers with high-peak power densities form less coagulum. Fibre specifications were found not to influence coagulum formation, and prototype modified tip fibres designed to prevent contact between the fibre tip and the vein wall did not eliminate coagulum formation. Conclusion: Microsecond-pulsed wave lasers with high-peak power densities may be a better choice to minimize soft thrombus formation during endovenous laser ablation treatments.

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Michalska, Maria, Paweł Grześ, and Jacek Swiderski. "High power, 100 W-class, thulium-doped all-fiber lasers." Photonics Letters of Poland 11, no. 4 (December 31, 2019): 109. http://dx.doi.org/10.4302/plp.v11i4.953.

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In this work, sub-kilowatt, compact thulium-doped fiber laser systems, operating at a wavelength of 1940 nm, have been presented. The continuous-wave laser power generated out of a single oscillator was 90 W with a slope efficiency of 56.7%. Applying a master oscillator – power amplifier configuration, an output power of 120.5 W with a slope efficiency of 58.2% was demonstrated. These are the first results of the works aimed at developing kW-class “eye-safe” laser systems in Poland. Full Text: PDF ReferencesZ. Liu, et al., "Implementing termination analysis on quantum programming", Sci. China Inf. Sci. 62, 41301 (2019) CrossRef S. D. Jackson, A. Sabella, D.G Lancaster, "Application and Development of High-Power and Highly Efficient Silica-Based Fiber Lasers Operating at 2 μm", IEEE J. Sel. Top. Quantum Electron. 13, 567, (2007). CrossRef E. Russell, N. Kavanagh, K. Shortiss, and F. C. G. Gunning, "Development of thulium-doped fibre amplifiers for the 2μm waveband", Proc. SPIE 10683, 106832Q (2018) CrossRef P. Peterka, B. Faure, W. Blanc, M. Karásek, and B. Dussardier, "Theoretical modelling of S-band thulium-doped silica fibre amplifiers", Opt. Quantum Electron. 36, 201 (2004) CrossRef M. Eichhorn, "Pulsed 2 μm fiber lasers for direct and pumping applications in defence and security", Proc. SPIE 7836, 78360B (2010). CrossRef O. Traxer and E. X. Keller, "Thulium fiber laser: the new player for kidney stone treatment? A comparison with Holmium:YAG laser", World J. Urol. 2019 Feb 6. doi: 10.1007/s00345-019-02654-5 CrossRef S. Das, "Optical parametric oscillator: status of tunable radiation in mid-IR to IR spectral range based on ZnGeP2 crystal pumped by solid state lasers", Opt. Quant. Electron. 51, 70 (2019) CrossRef M. Michalska, P. Hlubina, and J. Swiderski, "Mid-infrared Supercontinuum Generation to ∼4.7 μm in a ZBLAN Fiber Pumped by an Optical Parametric Generator", IEEE Photon. J 9, 3200207 (2017) CrossRef https://www.ipgphotonics.com DirectLink M.D. Burns, P. C. Shardlow, P. Barua, T. L. Jefferson-Brain, J. K. Sahu, and W. A.Clarkson, "47 W continuous-wave 1726 nm thulium fiber laser core-pumped by an erbium fiber laser", Opt. Lett. 44, 5230 (2019) CrossRef S.D. Jackson, "Cross relaxation and energy transfer upconversion processes relevant to the functioning of 2 μm Tm3+-doped silica fibre lasers", Opt. Commun. 230, 197 (2004). CrossRef X. Wang, P. Zhou, X. Wang, H. Xiao, and L. Si, "102 W monolithic single frequency Tm-doped fiber MOPA", Opt. Express 21, 32386 (2013) CrossRef K. Yin, R. Zhu, B. Zhang, G. Liu, P. Zhou, and J. Hou, "300 W-level, wavelength-widely-tunable, all-fiber integrated thulium-doped fiber laser", Opt. Express 24, 11085 (2016) CrossRef G. D. Goodno, L. D. Book, and J. E. Rothenberg, "600-W, single-mode, single-frequency thulium fibre laser amplifier", Proc. SPIE 7195, 71950Y (2009). CrossRef T. Ehrenreich, R. Leveille, I. Majid, K. Tankala, G. Rines, and P. Moulton, "1-kW, all-glass Tm: fiber laser", Proc. SPIE 7580, 1 (2010) DirectLink M. Michalska et al., "Highly stable, efficient Tm-doped fiber laser—a potential scalpel for low invasive surgery", Laser Phys. Lett. 13, 115101 (2016). CrossRef

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Ivanenko, A. V., B. N. Nyushkov, and S. V. Smirnov. "Generation of high-energy single pulses and pulse clusters in ytterbium fibre lasers with quasi-synchronous modulation of the pump power." Quantum Electronics 51, no. 12 (December 1, 2021): 1061–67. http://dx.doi.org/10.1070/qel17653.

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Abstract Additional capabilities of the method of quasi-synchronous pump power modulation developed by the authors for nanosecond high-energy pulsed oscillation of fibre lasers with a long-lived (about 1 ms) upper laser level are investigated. Using an Yb fibre laser as an example, it is shown that quasi-synchronous pump power modulation makes it possible to generate not only a periodic sequence of single nanosecond pulses, but also regular pulse clusters with a controlled number of nanosecond subpulses that make up a cluster. In addition, the feasibility of scaling the energy of laser pulses obtained by the method of quasi-synchronous modulation of the pump power is studied when proceeding to the use of active double-clad fibres and higher-power multimode pump sources. Pulses with energies up to 430 nJ are obtained in a laser configuration maintaining linear polarisation of radiation. The results obtained significantly expand the possibilities of applying the method of quasi-synchronous modulation of the pump power in conventional fibre lasers based on stimulated emission.

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9

Lekich, C., and P. Hannah. "Retained laser fibre: insights and management." Phlebology: The Journal of Venous Disease 29, no. 5 (March 28, 2013): 318–24. http://dx.doi.org/10.1177/0268355513483957.

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Objectives: To describe a case of retained endovenous laser fibre. To review the literature and Food and Drug Administration device failure reports. To suggest protocols for avoiding this complication and a method of removal. Methods: A case of retained fibre removal is described. Fibre removal techniques in vivo and ex vivo in a bovine model on the laboratory bench are presented. Results: Successful in vivo and ex vivo fibre removal was performed using duplex ultrasound scan guided phlebectomy techniques. Unexplained measured fibre-length discrepancies due to misleading manufacturer's packaging was discovered. Conclusions: Simple ultrasound-guided micro-phlebectomy techniques can be used to remove retained laser fibres in the office environment. Laser fibre length measurements before and after treatment are recommended. Some preventive guidelines are described to avoid, or at least diagnose immediately, this complication, such as the ‘Laser Eclipse Sign’.

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Sharp, Martin C., Roopesh Yadav, Andre Batako, and Paul W. French. "Fibre Laser Cleaning of Grinding Wheels." Key Engineering Materials 496 (December 2011): 55–60. http://dx.doi.org/10.4028/www.scientific.net/kem.496.55.

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The use of high power laser technology in the cleaning and dressing of grinding wheels has been the subject of several research projects worldwide and over the last 30 years. Several projects have reported beneficial outcomes however the process has not been implemented in production. The arrival of fibre lasers may provide a viable laser source for cleaning, and ultimately dressing, of wheels. This paper reports on some preliminary data confirming this potential and that supports the need for further research effort.

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Krylov, A. A., A. V. Gladyshev, A. K. Senatorov, A. N. Kolyadin, A. F. Kosolapov, M. M. Khudyakov, M. E. Likhachev, and I. A. Bufetov. "1.56-to-2.84 μm SRS conversion of chirped pulses of a high-power erbium fibre laser in a methane-filled hollow-core revolver fibre." Quantum Electronics 52, no. 3 (March 1, 2022): 274–77. http://dx.doi.org/10.1070/qel18003.

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Abstract Single-cascade 1.56-to-2.84 μm SRS conversion is demonstrated in a hollow-core revolver fibre filled with methane at a pressure of 25 atm under pumping by positively chirped pulses of a high-power erbium-doped all-fibre laser. At a maximum pump pulse energy of 34 μJ (average power 3.74 W) and a pump pulse duration of about 260 ps, ultrashort pulses (USPs) with a duration of 110 ps and an energy of 1.33 μJ (average power 133 mW) are achieved at the centre wavelength of 2.84 μm. The gas fibre Raman lasers based on hollow-core fibres with pumping by high-power fibre sources are promising for producing all-fibre systems emitting USPs in the mid-IR range.

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Mahrle, A., M. Lütke, and E. Beyer. "Fibre laser cutting: Beam absorption characteristics and gas-free remote cutting." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 224, no. 5 (November 5, 2009): 1007–18. http://dx.doi.org/10.1243/09544062jmes1747.

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Laser cutting is still the most common industrial application of CO 2 laser systems but currently available high-power fibre lasers seem to be an attractive alternative to the established CO 2 laser sources for several cutting tasks. Practical experience has shown that fibre lasers enable significantly increased travel rates in the case of inert-gas fusion cutting. This advantage in achieving higher cutting speeds in comparison to CO 2 laser cutting is however a clear function of the sheet thickness to be cut. In the first part of this article, possible reasons for this experimental fact are derived from a thermodynamic analysis of the process with consideration of the specific beam absorption characteristics under cutting conditions. After that, in the second part, a quite new laser cutting variant, namely the gas-free remote cutting process that considerably benefits from the high beam quality of fibre laser systems, is presented.

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Pile, David. "Fibre laser directions." Nature Photonics 7, no. 11 (October 30, 2013): 846–47. http://dx.doi.org/10.1038/nphoton.2013.306.

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Fermann, M. E., M. Hofer, F. Haberl, and S. P. Craig-Ryan. "Femtosecond fibre laser." Electronics Letters 26, no. 20 (1990): 1737. http://dx.doi.org/10.1049/el:19901109.

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Kudelin, Igor, Srikanth Sugavanam, and Maria Chernysheva. "Rotation Active Sensors Based on Ultrafast Fibre Lasers." Sensors 21, no. 10 (May 19, 2021): 3530. http://dx.doi.org/10.3390/s21103530.

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Gyroscopes merit an undeniable role in inertial navigation systems, geodesy and seismology. By employing the optical Sagnac effect, ring laser gyroscopes provide exceptionally accurate measurements of even ultraslow angular velocity with a resolution up to 10−11 rad/s. With the recent advancement of ultrafast fibre lasers and, particularly, enabling effective bidirectional generation, their applications have been expanded to the areas of dual-comb spectroscopy and gyroscopy. Exceptional compactness, maintenance-free operation and rather low cost make ultrafast fibre lasers attractive for sensing applications. Remarkably, laser gyroscope operation in the ultrashort pulse generation regime presents a promising approach for eliminating sensing limitations caused by the synchronisation of counter-propagating channels, the most critical of which is frequency lock-in. In this work, we overview the fundamentals of gyroscopic sensing and ultrafast fibre lasers to bridge the gap between tools development and their real-world applications. This article provides a historical outline, highlights the most recent advancements and discusses perspectives for the expanding field of ultrafast fibre laser gyroscopes. We acknowledge the bottlenecks and deficiencies of the presented ultrafast laser gyroscope concepts due to intrinsic physical effects or currently available measurement methodology. Finally, the current work outlines solutions for further ultrafast laser technology development to translate to future commercial gyroscopes.

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Arjyal, Bish, and Costas Galiotis. "Localised Stress Measurements in Composite Laminates Using a Raman Stress Sensor." Advanced Composites Letters 4, no. 2 (March 1995): 096369359500400. http://dx.doi.org/10.1177/096369359500400203.

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A new remote laser Raman stress/ strain sensor for localised measurements in polymer based composites, has been developed and tested. Measurements can be conducted in reinforcing fibres near the surface of laminates. For measurements in the bulk of composites, the exciting laser light has to be transported to the reinforcing fibres via an embedded fibre optic cable. The backscattered light is transmitted through the same fibre optic and is sent to the Raman spectrometer for analysis. The effect of the direction of the fibre optic cable with respect to the axis of the reinforcing fibres is examined. Finally, the relationships between the local fibre stress or strain obtained from the Raman sensor and the far field stress or strain measured conventionally, are established.

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Chernysheva, Maria, Aleksey Rozhin, Yuri Fedotov, Chengbo Mou, Raz Arif, Sergey M. Kobtsev, Evgeny M. Dianov, and Sergei K. Turitsyn. "Carbon nanotubes for ultrafast fibre lasers." Nanophotonics 6, no. 1 (January 6, 2017): 1–30. http://dx.doi.org/10.1515/nanoph-2015-0156.

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AbstractCarbon nanotubes (CNTs) possess both remarkable optical properties and high potential for integration in various photonic devices. We overview, here, recent progress in CNT applications in fibre optics putting particular emphasis on fibre lasers. We discuss fabrication and characterisation of different CNTs, development of CNT-based saturable absorbers (CNT-SA), their integration and operation in fibre laser cavities putting emphasis on state-of-the-art fibre lasers, mode locked using CNT-SA. We discuss new design concepts of high-performance ultrafast operation fibre lasers covering ytterbium (Yb), bismuth (Bi), erbium (Er), thulium (Tm) and holmium (Ho)-doped fibre lasers.

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Petkovšek, Rok, Vid Agrež, Jaka Petelin, Luka Černe, Udo Bünting, and Boštjan Podobnik. "Pulses on Demand in Fibre and Hybrid Lasers." Strojniški vestnik – Journal of Mechanical Engineering 65, no. 11-12 (November 18, 2019): 680–89. http://dx.doi.org/10.5545/sv-jme.2019.6352.

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This paper presents an investigation of pulse-on-demand operation in fibre and hybrid lasers. Two methods for efficient gain control that enable the generation of laser pulses at arbitrary times with controlled pulse parameters are presented. The method of direct modulation of the pump power in the high-power laser oscillator is shown to generate pulses with a duration in the nanosecond range, with repetition rates varying during operation from a single shot to over 1 MHz. An advanced method using a combination of marker and idler seeding a fibre amplifier chain is investigated. Such a system can easily achieve repetition rates of several tens of MHz. The lasers’ performances were successfully tested in a real environment on an industrial platform for laser transfer printing. Similar concepts were used for a laser source with ultrashort laser pulses (femtosecond range) on demand by using a mode-locked seed as a source and a solid-state amplifier to achieve high pulse energy and peak power.

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Hofmann, Marcel, Dirk Wenzel, Bernd Gulich, Heike Illing-Günther, and Daisy Nestler. "Development of Nonwoven Preforms Made of Pure Recycled Carbon Fibres (rCF) for Applications of Composite Materials." Key Engineering Materials 742 (July 2017): 555–61. http://dx.doi.org/10.4028/www.scientific.net/kem.742.555.

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For the development of an efficient and economic recycling process of carbon fibers (CF) still many technological challenges have to be mastered. One of them is the removal of all extraneous natural and synthetic fibres, e.g. polyester sewing threads. The objective of the research was to develop an in-line process for the removal of those extraneous fibres, which result from mechanical processes such as tearing. A promising approach for the removal of extraneous fibres from cut-off carbon-fibre material (CF) has been identified, getting recycled carbon fibres (rCF). For that purpose, the use of modern laser technologies is particularly promising. However, the focus was not the development of new laser systems, but the adaptation of existing technologies and their integration into textile processing steps for carbon fibre recycling. In addition to the removal of the extraneous fibres, the degree of CF losses and quality degradation due to fibre damage have been analysed and compared with optimum fibre characteristics. The separation has been experimented and corresponding laser parameters have been defined. Finally, the obtained carbon-fibre material has been tested with regard to its processability in textile manufacturing processes (dry non-woven fabric production) up to carbon fibre reinforced plastics (CFRP). For the evaluation of the material for potential applications, test plates from irradiated and non-irradiated material have been used. The performed tensile and flexural tests have proved that the irradiated material has similar properties compared to the non-exposed one.

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Skvortsov, M. I., S. R. Abdullina, A. A. Wolf, A. V. Dostovalov, A. E. Churin, O. N. Egorova, S. L. Semjonov, K. V. Proskurina, and S. A. Babin. "Single-frequency erbium-doped fibre laser with random distributed feedback based on disordered structures produced by femtosecond laser radiation." Quantum Electronics 51, no. 12 (December 1, 2021): 1051–55. http://dx.doi.org/10.1070/qel17650.

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Abstract Inscription of structures by a femtosecond laser beam allows one to produce disordered structures capable of increasing the Rayleigh backscatter intensity in the fibre at relatively low induced losses, which makes them potential candidates for use as reflectors in fibre lasers. Here we report a narrow-band erbium fibre laser with random distributed feedback produced by femtosecond laser writing in half-open cavity and ring cavity configurations. In the half-open cavity configuration, single-frequency lasing is observed at output powers up to 2.8 W, with a linewidth near 10 kHz. In the ring cavity configuration, single-frequency operation is observed over the entire range of output powers studied. At the highest output power, 7 mW, the linewidth does not exceed 0.7 kHz.

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Heckner, Tobias, Michael Seitz, Sven Robert Raisch, Gerrit Huelder, and Peter Middendorf. "Selective Laser Sintering of PA6: Effect of Powder Recoating on Fibre Orientation." Journal of Composites Science 4, no. 3 (August 6, 2020): 108. http://dx.doi.org/10.3390/jcs4030108.

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In Selective Laser Sintering, fibres are strongly orientated during the powder recoating process. This effect leads to an additional increase of anisotropy in the final printed parts. This study investigates the influence of process parameter variation on the mechanical properties and the fibre orientation. A full factorial design of experiment was created to evaluate the processing parameters of recoating speed, layer thickness and laser power on the part’s modulus of elasticity. Based on the mechanical testing, computed tomography was applied to selected samples to investigate the process-induced fibre microstructure, and calculate the fibre orientation tensors. The results show increasing part stiffness in the deposition direction, with decreasing layer thickness and increasing laser power, while the recoating speed only shows little effect on the mechanical performance. This complies with computed tomography imaging results, which show an increase in fibre orientation with smaller layer thickness. With thinner layers, and hence smaller shear gaps, shear stresses induced by the roller during recoating increase significantly, leading to excessive fibre reorientation and alignment. The high level of fibre alignment implies an increase of strength and stiffness in the recoating direction. In addition, thinner layer thickness under constant laser energy density results in improved melting behaviour, and thus improved fibre consolidation, consequently further increasing the mechanical properties. Meanwhile, the parameters of recoating speed and laser power do not have a significant impact on fibre orientation within their applicable process windows.

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Dorosz, D., J. Dorosz, A. Zając, J. Żmojda, and M. Kochanowicz. "Active optical fibres for application in laser and broadband ASE sources." Bulletin of the Polish Academy of Sciences: Technical Sciences 60, no. 4 (December 1, 2012): 673–82. http://dx.doi.org/10.2478/v10175-012-0078-6.

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Abstract The article brings into focus the present state of technology employing active fibres doped with rare earth (RE) ions for applications requiring power supply of several dozen watts and broadband ASE sources. Current trends in development of glasses and in construction of active fibres used in fibre sources of radiation within VIS-NIR range are presented. Technological constraints in the doping of fibre core glasses are discussed, with particular consideration of optimal RE concentration for technical applications. Characteristics of glasses are offered, and the glasses are used for manufacturing optical fibres with luminescence within the visible as well as near- and mid-infrared ranges. Also, requirements and luminescence properties concerning glasses co-doped with e.g. Nd3+/Yb3+,Tm3+/Ho3+ and Yb3+/Tb3+ are discussed. Results of research on the impact of technological parameters of glass matrices on luminescence properties of core glasses and optical fibres are quoted. For the doped glasses of which luminescence in a wide spectral range is desired, conditions for their processing into optical fibre systems are mentioned. Additionally, the impact of phonon energy in the glass on producing emission in a specified spectral range is analyzed. Furthermore, the article presents directions of technological studies to solve problems persisting in the phase of glass matrix design, as well as in determining the influence of fibre drawing process on the luminescence properties of core glasses and optical fibres, confirming the differences in luminescence stemming from the drawing process. Finally, some original designs of core glasses and active multicore fibre systems devised for construction of fibre radiation sources are presented.

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Lachman, Martin, and Jiří Šafka. "Experimental Determination of the Focal Length of a Laser Beam from the Output Nozzle of a Laser Cutting Head." Key Engineering Materials 756 (September 2017): 71–79. http://dx.doi.org/10.4028/www.scientific.net/kem.756.71.

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Laser technologies are considered to be unconventional technologies. Laser cutting is one of the most popular industrial operations that use a laser beam. Fibre lasers are most commonly used for cutting metallic materials. The aim of this paper is to experimentally demonstrate a procedure for determining the focal length of a laser beam from the output of the cutting head of a JK400FL fibre laser. Along with other factors, the correct position of the focal point of a laser beam cutting materials, plays a vital role in the quality of the cut and also in determining the cutting speed. It is possible to use a higher cutting speed of the laser machine, without compromising the quality of the cut.

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Fesler, K. A., B. Y. Kim, and H. J. Shaw. "Fibre gyro experiment using fibre laser source." Electronics Letters 25, no. 8 (1989): 534. http://dx.doi.org/10.1049/el:19890366.

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Ahmad, H., S. N. A. Sakeh, Z. Muda, M. Z. Zulkifli, and S. W. Harun. "Multiwavelength Brillouin fibre laser in two-mode fiber." Journal of Modern Optics 64, no. 17 (April 10, 2017): 1744–50. http://dx.doi.org/10.1080/09500340.2017.1314027.

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Zaremba, Matous, Milan Maly, Vojtech Mraz, and Jan Jedelsky. "Comparison of fibre-based phase Doppler analysers." EPJ Web of Conferences 269 (2022): 01071. http://dx.doi.org/10.1051/epjconf/202226901071.

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Laser diagnostics techniques are widely used in experimental fluid mechanics. By far the most widely used systems for getting spatial velocity fields and turbulence data are laser Doppler anemometers (LDA). Further, in the cases of two-phase flows phase Doppler analysers (PDA) are typically chosen to measure the size and velocity of the droplets or bubbles. The PDA system is non-intrusive laser technique with high spatial and temporal resolution. Moreover, the PDA system does not require additional calibration as, for example, hot-wire anemometers. However, with a growing number of PDA users, there is a need for verification of the results among the workplaces and systems themselves. The current paper deals with the comparison of two fibre-based PDA systems. The main scope of the investigation is an evaluation of the system's age and the influence of lasers type. One of the systems is older, operated with Argon-Ion laser and the second one is brand new equipped with Diode-pumped solid-state lasers. Both have the same optics and were manufactured by the same company. Various properties of the PDA system are tested to show particular influence on the quality of results when measuring in a spray generated by a small air-blast atomizer.

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Komorowski, Paweł, Krzysztof Anders, Urszula Zdulska, and Ryszard Piramidowicz. "Erbium doped ZBLAN fiber laser operating in the visible - feasibility study." Photonics Letters of Poland 9, no. 3 (September 30, 2017): 85. http://dx.doi.org/10.4302/plp.v9i3.769.

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This work is focused on developing all-fiber green laser in hybrid geometry, based on combination of Er:ZBLAN active fiber and silica fiber-based passive components of optical resonator and deploying Fiber Bragg Gratings (FBGs) as highly selective mirrors for green spectral range. The scope of work covers fundamental spectroscopic characterization of Er:ZBLAN samples, determination of key spectroscopic parameters, modelling the lasing properties and lasing experiments in different pumping geometries. Full Text: PDF ReferencesW.P. Risk, T.R. Gosnell, A.V. Nurmikko, "Compact blue-green lasers", Cambridge University Press. (2003) CrossRef J.Y. Allain, M. Monerie, and H. Poignant, "Tunable green upconversion erbium fibre laser", Electronics Lett., 28 (1992) 111-113 CrossRef Z . Luo, Q. Ruan, M. Zhong, Y. Cheng, R. Yang, B. Xu, H. Xu, Z. Cai, "Compact self-Q-switched green upconversion Er:ZBLAN all-fiber laser operating at 543.4 nm", Optics Lett. 41 (2016) 2258-2261 CrossRef D. E. McCumber, "Einstein relations connecting broadband emission and absorption spectra", Physical Review 136 (1964) 954-957 CrossRef

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Harun, Sulaiman Wadi, Mukul C. Paul, Shyamal Das, Anirban Dhar, and Harith Ahmad. "Mode-locked Thulium Ytterbium co-Doped Fiber Laser with Graphene Saturable Absorber." Photonics Letters of Poland 8, no. 4 (December 31, 2016): 104. http://dx.doi.org/10.4302/plp.2016.4.05.

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A passively mode-locked Thulium Ytterbium co-doped fiber laser (TYDFL) is demonstrated using a graphene polyvinyl alcohol saturable absorber as the mode-locker. With 980 nm multimode pumping, the laser operates at 1942.95 nm with repetition rate of 11.76 MHz. The pulse width is calculated to be around 52.85 ps. The maximum pulse energy of 1190.5 pJ is achieved at pump power of 1750 mW. Full Text: PDF ReferencesJ. Sotor et al., "Ultrafast thulium-doped fiber laser mode locked with black phosphorus", Opt. Lett. 40, 3885-3888 (2015) CrossRef J. Wang et al., "152 fs nanotube-mode-locked thulium-doped all-fiber laser", Nature Scientific Reports 6, 28885 (2016) CrossRef I. M. Babar et al., "Double-clad thulium/ytterbium co-doped octagonal-shaped fibre for fibre laser applications", Ukr. J. Phys. Opt. 15, 173-183 (2014) CrossRef Harun et al., "Mode-locked bismuth-based erbium-doped fiber laser with stable and clean femtosecond pulses output", Laser Phys. Lett. 8, 449-452 (2011) CrossRef M. A. Ismail et al., "Nanosecond soliton pulse generation by mode-locked erbium-doped fiber laser using single-walled carbon-nanotube-based saturable absorber", Applied Optics 51, 8621-8624 (2012) CrossRef G. Sobon et al., "Graphene Oxide vs. Reduced Graphene Oxide as saturable absorbers for Er-doped passively mode-locked fiber laser", Opt. Express 20, 19463-19473 (2012) CrossRef G. Sobon et al., "Thulium-doped all-fiber laser mode-locked by CVD-graphene/PMMA saturable absorber", Opt. Express 21, 12797-12802 (2013) CrossRef

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29

Kleine-Ostmann, T., P. Knobloch, R. Caspary, M. Hofmann, and M. Koch. "Dual-wavelength fibre laser." Electronics Letters 38, no. 7 (2002): 309. http://dx.doi.org/10.1049/el:20020211.

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30

Miniscalco, W. J., L. J. Andrews, B. A. Thompson, R. S. Quimby, L. J. B. Vacha, and M. G. Drexhage. "1.3μm fluoride fibre laser." Electronics Letters 24, no. 1 (January 7, 1988): 28–29. http://dx.doi.org/10.1049/el:19880019.

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31

Smith, K., I. R. Armitage, R. Wyatt, N. J. Doran, and S. M. J. Kelly. "Erbium fibre soliton laser." Electronics Letters 26, no. 15 (1990): 1149. http://dx.doi.org/10.1049/el:19900744.

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32

Dianov, Evgenii M., V. V. Dvoyrin, V. M. Mashinsky, A. A. Umnikov, M. V. Yashkov, and A. N. Gur'yanov. "CW bismuth fibre laser." Quantum Electronics 35, no. 12 (December 31, 2005): 1083–84. http://dx.doi.org/10.1070/qe2005v035n12abeh013092.

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33

Oktem, Bulent, Coşkun Ülgüdür, and F. Ömer Ilday. "Soliton–similariton fibre laser." Nature Photonics 4, no. 5 (March 21, 2010): 307–11. http://dx.doi.org/10.1038/nphoton.2010.33.

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Fotiadi, Andrei A. "An incoherent fibre laser." Nature Photonics 4, no. 4 (April 2010): 204–5. http://dx.doi.org/10.1038/nphoton.2010.76.

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35

Dominic, V., S. MacCormack, R. Waarts, S. Sanders, S. Bicknese, R. Dohle, E. Wolak, P. S. Yeh, and E. Zucker. "110 W fibre laser." Electronics Letters 35, no. 14 (1999): 1158. http://dx.doi.org/10.1049/el:19990792.

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36

Salminen, A., H. Piili, and T. Purtonen. "The characteristics of high power fibre laser welding." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 224, no. 5 (March 19, 2010): 1019–29. http://dx.doi.org/10.1243/09544062jmes1762.

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Laser welding has an ever growing role in manufacturing technology. Keyhole laser welding is the most important laser welding process in metal industry when exceeding the 1 mm weld penetration. This process uses efficiently the high energy density of a laser beam to vaporize and melt materials, thus producing a keyhole in the material via which the energy is brought to it. The requirements from customer side and the development of new materials have been giving justification for the development of new laser types suitable for material processing with ever higher power values. In contrast, the development of laser technologies has made it possible to build more powerful lasers with excellent beam properties and good electrical efficiency. New laser sources with good absorption and beam quality make the laser welding even more efficient when throughput and efficiency are considered. They show their ability to produce narrower welds with lower line energy. However, the validation of actual keyhole shape, size, and behaviour against the models is still lacking because of the difficulties in performing the measurements of the actual dimensions. It has been shown that the better the beam quality the higher the welding speed. When welding with high power, good beam quality, and wavelength close to 1000 nm, there are some obstacles to overcome, which are caused by high absorption and power density. Typically, problems, such as thermal lensing, can be avoided with proper parameter and tool selection. Typically, the size of the keyhole is according to the focal point size, and the stability of the keyhole plays a major role when considering the ability of the laser welding process to produce high quality welds.

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Meszlényi, György, and Enikő Bitay. "Analyis of Fibre Laser’s Optical Construction from the End of the Beam Guiding Optical Fibre to the Focal Spot." Acta Materialia Transylvanica 5, no. 2 (October 1, 2022): 72–77. http://dx.doi.org/10.33924/amt-2022-02-05.

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Abstract In material-processing fiber lasers, the resonator in the closed box produces the laser radiation. Even with the same resonator, the diameter of the laser beam transporting fiber optics and the properties of the optical elements in the laser focusing head decide the cross-section of the focused laser beam used for machining. If we summarize the formulas in different sources in the literature, we can predict the effect of each optical element: what will happen if we choose another focusing lens, put a beam expander in the system, set on the beam expander how many times the laser beam expands. The other important point is that if we want to repeat an experiment or start a production process based on a scientific publication, then in addition to the resonator, it would be good to know the data of the optical elements in the focusing head, which is usually incomplete in the presented articles, but we can determine them approximately using the four formulas listed in the article.

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Polyakov, V. E., A. V. Emelyanov, A. A. Zakutaev, and V. V. Shirobokov. "ACTIVE MEDIUM FOR FIBRE LASERS AND TECHNOLOGY FOR PRODUCTION THEREOF." Journal of Applied Spectroscopy 89, no. 1 (January 21, 2022): 110–17. http://dx.doi.org/10.47612/0514-7506-2022-89-1-110-117.

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Invention relates to laser equipment. Active medium for fiber lasers contains a structurally-activated epoxy oligomer with molecules of organic dyes and a hardener. Curing agent used is finely dispersed glass with chemically activated reactive groups on the surface with the following ratio of ingredients pts.wt.: organic dye 0.0075-01; epoxy oligomer 8.0-31.5; fine-dispersed glass with chemically activated surface 68.4925-91.9. Technical result consists in enabling adjustment of the value of the refractive index of the active fibre core.

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Scurr, J. R. H., J. Martin, T. V. How, I. Gambardella, and J. A. Brennan. "Retained Laser Fibre Following Endovenous Laser Ablation." EJVES Extra 13, no. 2 (February 2007): 30–32. http://dx.doi.org/10.1016/j.ejvsextra.2006.11.001.

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40

Scurr, J. R. H., J. Martin, T. V. How, I. Gambardella, and J. A. Brennan. "Retained Laser Fibre Following Endovenous Laser Ablation." European Journal of Vascular and Endovascular Surgery 33, no. 3 (March 2007): 377. http://dx.doi.org/10.1016/j.ejvs.2006.11.017.

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41

Zhang, Naizhong, Suzana Turk, Claire Davis, Wing K. Chiu, Tommy Boilard, and Martin Bernier. "Fatigue Performance of Type I and Type II Fibre Bragg Gratings Fabricated by Femtosecond Laser Inscription through the Coating." Sensors 22, no. 22 (November 15, 2022): 8812. http://dx.doi.org/10.3390/s22228812.

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Strain sensing technology using fibre Bragg grating (FBG) sensors is an attractive capability for aerospace structural health monitoring (SHM) and assessment because they offer resistance to harsh environments, low maintenance, and potential for high density and high strain sensing. The development of FBG inscription techniques through the fibre polymer coating using infrared (IR) lasers has overcome the mechanical weaknesses introduced by removal of the fibre coating, which is typically required for conventional UV laser inscription of FBGs. Type I and Type II femtosecond gratings are fabricated using through-coating inscription techniques, but the higher laser energy used for Type II gratings damages the glass fibre core, impacting mechanical performance. This paper investigates the fatigue performance of Type I and Type II through-coating FBG sensors with different fibre geometries and photosensitisation approaches to evaluate their overall reliability and durability, with a view to assess their performance for potential use in civil and defence SHM applications. The fatigue performance of FBG sensors was assessed under high-strain and high-frequency mechanical loading conditions by using a custom-designed electro-dynamically actuated loading assembly. In addition, pre- and post-fatigue microscopic analyses and high-resolution reflection spectrum characterisation were conducted to investigate the failure regions of the fibres and the effect of fatigue loading on reflection spectrum features. As expected, Type I gratings had a significantly higher fatigue life compared to Type II gratings. However, Type II gratings performed significantly better than conventional UV laser-inscribed FBGs and electrical foil strain gauges. Type II gratings withstand higher temperatures, and are therefore more suitable for application in harsh environments.

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Muc, Sylwia, and Tadeusz Gudra. "Transmission of Ultrasonic Waves Via Optical Silica Glass Fiber Doped by 7.5% of TiO2 with the Use of Power Sandwich Transducer." Archives of Acoustics 36, no. 1 (February 1, 2011): 141–50. http://dx.doi.org/10.2478/v10168-011-0010-3.

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Abstract The possibility of acoustic wave propagation in optical waveguides creates new prospects for simultaneous transmission of laser beams and ultrasonic waves. Combined laser-ultrasonic technology could be useful in e.g. surgical treatment. The article presents the results of experimental studies of transmission of ultrasonic wave in optical fibres, the core of which is doped by 7.5% of TiO2, using a sandwich-type transducer. It also presents amplitude characteristics of an ultrasonic signal propagated in the optical fibre. Authors studied the effect which the length of the fibre has on the achieved output signal amplitudes. They presented the relation of the output signal amplitude from a capacitive sensor to the power applied to the sandwich-type transducer. The obtained results were compared with the results produced when using an optical fibre with a core doped by 3% of GeO2, in order to select optical fibre suitable for simultaneous transmission of ultrasonic waves and laser rays.

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Jauncey, I. M., L. Reekie, R. J. Mears, D. N. Payne, C. J. Rowe, D. C. J. Reid, I. Bennion, and C. Edge. "Narrow-linewidth fibre laser with integral fibre grating." Electronics Letters 22, no. 19 (1986): 987. http://dx.doi.org/10.1049/el:19860675.

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44

Liu, H. Y., H. B. Liu, G. D. Peng, and P. L. Chu. "Polymer optical fibre Bragg gratings based fibre laser." Optics Communications 266, no. 1 (October 2006): 132–35. http://dx.doi.org/10.1016/j.optcom.2006.04.026.

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45

Alyshev, S. V., K. E. Ryumkin, A. V. Shubin, O. I. Medvedkov, V. F. Khopin, A. N. Gur'yanov, and E. M. Dianov. "Fibre laser based on tellurium-doped active fibre." Quantum Electronics 44, no. 2 (February 28, 2014): 95–97. http://dx.doi.org/10.1070/qe2014v044n02abeh015367.

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46

Kim, H. K., S. K. Kim, and B. Y. Kim. "Polarimetric fibre laser sensors using Er-doped fibre." Optical and Quantum Electronics 27, no. 5 (May 1995): 481–85. http://dx.doi.org/10.1007/bf00563587.

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47

Pannier, F., E. Rabe, J. Rits, A. Kadiss, and U. Maurins. "Endovenous laser ablation of great saphenous veins using a 1470 nm diode laser and the radial fibre – follow-up after six months." Phlebology: The Journal of Venous Disease 26, no. 1 (December 9, 2010): 35–39. http://dx.doi.org/10.1258/phleb.2010.009096.

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Background Endovenous laser ablation (EVLA) is an efficient method to treat insufficient great saphenous veins (GSV) with high occlusion rates.1–5 Most studies used 810, 940 or 980 nm diode lasers and a bare fibre.1,2,6 Moderate postoperative pain and bruising are frequent findings.2,6 Laser systems with higher wavelengths like 1470 nm with a higher absorption in water show less pain and bruising after the procedure.7–9 A newly-developed fibre (radial fibre, Biolitec) emits the laser energy radially around the tip directly into the venous wall contrary to the bare fibre.9 The aim of this study was to demonstrate the outcome and side-effects after EVLA of GSV with a 1470 nm diode laser (Ceralas E, Biolitec) by using the radial fibre. Methods Non-randomized, prospective study including 50 unselected limbs of 50 patients with a duplex sonographically verified incompetent GSV. EVLA was performed with a 1470 nm diode laser (Ceralas E, Biolitec) and a radial fibre. In the same session all insufficient tributaries were treated by phlebectomy. Tumescent local anaesthesia with 0.05% lidocaine was applied perivenously. Laser treatment was carried out in a continuous mode with a power of 15 W. Compression stockings (30 mmHg) were applied for one month. Postinterventional checkups took place one, 10, 30 days and six months after the procedure. Results Three patients were lost to follow-up. The average linear endovenous energy density (LEED) was 90.8 J/cm vein (SD 35.3). At the six month follow-up all treated veins remained occluded and no new reflux in the treated segments occurred. No recurrent varicose veins had occurred so far. No severe complications such as deep venous thrombosis could be detected. In four patients at 30 days and three patients at six months local paresthesia occurred in the region of EVLA. Forty-four percent of patients did not have any pain after the treatment and 50% did not take any analgesic tablets at any time after the procedure. Postoperative ecchymoses in the track of the treated GSV was rare. In 80% of the limbs, no ecchymoses was observed after the treatment. Conclusion EVLA of GSV with a radially emitting laser fibre by using a 1470 nm diode laser is a safe and efficient treatment option.

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Sharp, J. H., C. W. P. Shi, and H. C. Seat. "Er-Doped Sapphire Fibre Temperature Sensors Using Upconversion Emission." Measurement and Control 34, no. 6 (July 2001): 170–74. http://dx.doi.org/10.1177/002029400103400604.

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We report the production of Er:Al2O3 and Er:Yb:Al2O3 fibres using the LHPG method for application as fibre temperature sensors. Intense upconversion emission in the blue, green and red was observed from these fibres when pumped with a laser diode at 965nm. The lifetime and the integrated intensity of the upconversion signal was characterised as function of laser power and temperature. Results indicate the ratiometric analysis of the integrated intensities provides a suitable transduction mechanism for temperatures up to 1000K.

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Wiemer, Niels, Alexander Wetzel, Maximilian Schleiting, Philipp Krooß, Malte Vollmer, Thomas Niendorf, Stefan Böhm, and Bernhard Middendorf. "Effect of Fibre Material and Fibre Roughness on the Pullout Behaviour of Metallic Micro Fibres Embedded in UHPC." Materials 13, no. 14 (July 14, 2020): 3128. http://dx.doi.org/10.3390/ma13143128.

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The use of micro fibres in Ultra-High-Performance Concrete (UHPC) as reinforcement increases tensile strength and especially improves the post-cracking behaviour. Without using fibres, the dense structure of the concrete matrix results in a brittle failure upon loading. To counteract this behaviour by fibre reinforcement, an optimal bond between fibre and cementitious matrix is essential. For the composite properties not only the initial surfaces of the materials are important, but also the bonding characteristics at the interfacial transition zone (ITZ), which changes upon the joining of both materials. These changes are mainly induced by the bond of cementitious phases on the fibre. In the present work, three fibre types were used: steel fibres with brass coating, stainless-steel fibres as well as nickel-titanium shape memory alloys (SMA). SMA fibres have the ability of “remembering” an imprinted shape (referred to as shape memory effect), triggered by thermal activation or stress, principally providing for superior performance of the fibre-reinforced UHPC. However, previous studies have shown that NiTi-fibres have a much lower bond strength to the concrete matrix than steel fibres, eventually leading to a deterioration of the mechanical properties of the composite. Accordingly, the bond between both materials has to be improved. A possible strategy is to roughen the fibre surfaces to varying degrees by laser treatment. As a result, it can be shown that laser treated fibres are characterised by improved bonding behaviour. In order to determine the bond strength of straight, smooth fibres of different metal alloy compositions, the present study characterized multiple fibres in series with a Compact-Tension-Shear (CTS) device. For critical evaluation, results obtained by these tests are compared with the results of conventional testing procedures, i.e., bending tests employing concrete prisms with fibre reinforcements. The bond behaviour is compared with the results of the flexural strength of prisms (4 × 4 × 16 cm3) with fibre reinforcements.

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Allen, C. M., G. Verhaeghe, P. A. Hilton, Chris P. Heason, and Philip B. Prangnell. "Laser and Hybrid Laser-MIG Welding of 6.35 and 12.7mm Thick Aluminium Aerospace Alloy." Materials Science Forum 519-521 (July 2006): 1139–44. http://dx.doi.org/10.4028/www.scientific.net/msf.519-521.1139.

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Fusion welding of 7xxx aluminium alloy plates has been investigated for aerospace applications using autogenous laser welding and hybrid laser-MIG welding. Nd:YAG and Yb-fibre lasers have been used, with two different focussed spot sizes in each case. Autogenous and hybrid welding of 12.7mm thick plate using the Yb-fibre laser with a 0.6mm diameter spot was selected for further development, on the basis of penetration and weld quality achieved. These welds were acceptable to the highest quality class B (stringent) of BS EN ISO 13919-2:2001, with a porosity of only 0.3% of the cross-sectional area of the weld, and close to class A of AWS D17.1. Transverse proof strengths of ~60% of parent material were achieved. Development of hybrid welding is ongoing with novel fillers to refine weld metal grain structure and improve weld properties.

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Journal articles on the topic 'Fibre Laser'

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