{ "types" : { "Bookmark" : { "pluralLabel" : "Bookmarks" }, "Publication" : { "pluralLabel" : "Publications" }, "GoldStandardPublication" : { "pluralLabel" : "GoldStandardPublications" }, "GoldStandardBookmark" : { "pluralLabel" : "GoldStandardBookmarks" }, "Tag" : { "pluralLabel" : "Tags" }, "User" : { "pluralLabel" : "Users" }, "Group" : { "pluralLabel" : "Groups" }, "Sphere" : { "pluralLabel" : "Spheres" } }, "properties" : { "count" : { "valueType" : "number" }, "date" : { "valueType" : "date" }, "changeDate" : { "valueType" : "date" }, "url" : { "valueType" : "url" }, "id" : { "valueType" : "url" }, "tags" : { "valueType" : "item" }, "user" : { "valueType" : "item" } }, "items" : [ { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/247ed170338ffb5ae11fcca43e269739f/fzai", "tags" : [ "beam-shaping","core-ring","ifsw","laser-welding","myown","pores","steel" ], "intraHash" : "47ed170338ffb5ae11fcca43e269739f", "interHash" : "a02fa234b745914fb6c1dc1e582f2baf", "label" : "Core-ring Laser Welding: the Influence of Ring Diameter on the Capillary Dynamics and the Formation of Pores in the Resulting Weld", "user" : "fzai", "description" : "", "date" : "2026-03-11 11:31:22", "changeDate" : "2026-03-11 11:31:22", "count" : 2, "pub-type": "article", "journal": "Lasers in Manufacturing and Materials Processing", "year": "2026", "url": "https://doi.org/10.1007/s40516-026-00331-1", "author": [ "Felix Zaiß","John Powell","Michael Haas","Christian Diegel","Klaus Schricker","Jean Pierre Bergmann","Christoph Spurk","Marc Hummel","Alexander Olowinsky","Felix Beckmann","Julian Moosmann","Christian Hagenlocher","Thomas Graf" ], "authors": [ {"first" : "Felix", "last" : "Zaiß"}, {"first" : "John", "last" : "Powell"}, {"first" : "Michael", "last" : "Haas"}, {"first" : "Christian", "last" : "Diegel"}, {"first" : "Klaus", "last" : "Schricker"}, {"first" : "Jean Pierre", "last" : "Bergmann"}, {"first" : "Christoph", "last" : "Spurk"}, {"first" : "Marc", "last" : "Hummel"}, {"first" : "Alexander", "last" : "Olowinsky"}, {"first" : "Felix", "last" : "Beckmann"}, {"first" : "Julian", "last" : "Moosmann"}, {"first" : "Christian", "last" : "Hagenlocher"}, {"first" : "Thomas", "last" : "Graf"} ], "abstract": "Double-core fibers that deliver laser beams with adjustable amounts of power to the central core and the surrounding ring component of the fiber are of major interest for optimizing laser welding processes. However, the central focussed laser spot and the ring diameters are fixed by the fiber dimensions, the focusing optics, and the laser systems involved. This work investigates the influence of different ring beam diameters, with a constant central spot diameter, on the capillary dynamics and the formation of pores in the resulting welds in 1.4301 stainless steel (X5CrNi18-10, AISI 304). The different core-ring configurations were achieved using specially designed beam-shaping optics. The generation of pores during the welding process was examined by means of synchrotron X-ray imaging. The results show that different ring diameters have a profound effect on the melt pool geometry, the capillary shape and the location of the capillary collapse which gives rise to pore formation in the weld. In the examples presented here, larger ring diameters extended the melt pool in the direction of welding without contributing directly to the capillary evaporation. In this case the narrow, deep capillaries which are created by the core beam alone can bulge and collapse, trapping vapor and gas to create large pores. If, however, the ring beam has a small enough diameter, it can help to produce a wider capillary which does not trap gas and create pores in the same way. The mechanisms by which large bubbles in the melt can result in non-spherical pores in the weld are also explained.", "language" : "en", "issn" : "2196-7237", "doi" : "10.1007/s40516-026-00331-1", "bibtexKey": "ZaißCoreRingPores2026" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2aa26ab4820508003cedb4ccea38fbe08/fzai", "tags" : [ "beam-shaping","capillary","core-ring","ifsw","myown","peer","spatter","synchrotron","x-ray" ], "intraHash" : "aa26ab4820508003cedb4ccea38fbe08", "interHash" : "648b80e36d7fa93974a22c78884f108b", "label" : "The influence of different core-ring intensity distributions on the capillary shape and resulting weld in laser welding of steel", "user" : "fzai", "description" : "", "date" : "2025-12-14 14:24:39", "changeDate" : "2025-12-14 14:26:57", "count" : 3, "pub-type": "article", "journal": "Optics & Laser Technology","publisher":"Elsevier BV", "year": "2026", "url": "http://dx.doi.org/10.1016/j.optlastec.2025.114495", "author": [ "Felix Zaiß","John Powell","Michael Haas","Johannes Wahl","Christian Diegel","Klaus Schricker","Jean Pierre Bergmann","Marc Hummel","Christoph Spurk","Alexander Olowinsky","Felix Beckmann","Julian Moosmann","Christian Hagenlocher","Thomas Graf" ], "authors": [ {"first" : "Felix", "last" : "Zaiß"}, {"first" : "John", "last" : "Powell"}, {"first" : "Michael", "last" : "Haas"}, {"first" : "Johannes", "last" : "Wahl"}, {"first" : "Christian", "last" : "Diegel"}, {"first" : "Klaus", "last" : "Schricker"}, {"first" : "Jean Pierre", "last" : "Bergmann"}, {"first" : "Marc", "last" : "Hummel"}, {"first" : "Christoph", "last" : "Spurk"}, {"first" : "Alexander", "last" : "Olowinsky"}, {"first" : "Felix", "last" : "Beckmann"}, {"first" : "Julian", "last" : "Moosmann"}, {"first" : "Christian", "last" : "Hagenlocher"}, {"first" : "Thomas", "last" : "Graf"} ], "volume": "194","pages": "114495","abstract": "Laser welding was carried out using a co-axial core-ring beam, with independent control of the power to the core\r\nand the ring. The welding process was observed using high-power X-rays and high-speed imaging equipment.\r\nAdjusting the relative powers of the core and the ring beams was found to have profound effects on the shape of\r\nboth the capillary created and the weld melt pool. Moderate laser power densities in the ring were found to\r\nincrease the top diameter of the weld pool and reduce fluctuations in the welding process. High laser power\r\ndensities in the ring led to the creation of a second capillary which largely acted independently of the capillary\r\ngenerated by the laser power in the core. At high power densities and welding speeds the two capillaries were\r\nalmost completely separated in the direction of travel.", "issn" : "0030-3992", "doi" : "10.1016/j.optlastec.2025.114495", "bibtexKey": "Zaiss_CR_Distrib_2026" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/264b550af13f6809910f6de93990525f4/fzai", "tags" : [ "aluminum","beam-shaping","copper","core-ring","e-mobility","mplc","myown","pores","spatter" ], "intraHash" : "64b550af13f6809910f6de93990525f4", "interHash" : "e2d83efb621f29d9f235c7dbe3f859b2", "label" : "Pores and Spatters reduction for Copper and Aluminium Laser\r\nWelding with MPLC Beam-Shaping Solutions", "user" : "fzai", "description" : "", "date" : "2024-11-06 07:49:05", "changeDate" : "2024-11-06 07:49:05", "count" : 2, "pub-type": "proceedings", "series": "Industrial Paper 2024", "year": "2024", "url": "https://www.lane-conference.org/industrial-paper-2024/", "author": [ "Pallier Gwenn","Adeline Orieux","Avinash Kumar","Marc Hummel","Felix Zaiß","Carlos Duran","Tobias Florian","Andreas Otto","Guillaume Labroill" ], "authors": [ {"first" : "Pallier", "last" : "Gwenn"}, {"first" : "Adeline", "last" : "Orieux"}, {"first" : "Avinash", "last" : "Kumar"}, {"first" : "Marc", "last" : "Hummel"}, {"first" : "Felix", "last" : "Zaiß"}, {"first" : "Carlos", "last" : "Duran"}, {"first" : "Tobias", "last" : "Florian"}, {"first" : "Andreas", "last" : "Otto"}, {"first" : "Guillaume", "last" : "Labroill"} ], "volume": "13th CIRP Conference on Photonic Technologies [LANE 2024]","abstract": "The electric vehicle (EV) market is experiencing rapid growth, leading to a significant push towards innovation. One of the\r\ncritical challenges is Copper and Aluminum laser welding. These materials are inherently more difficult to weld and the welding\r\ncriteria are more stringent (limited porosity and spatters).\r\nAn advanced beam shaping modules have been developed using Multi-Plane Light Conversion (MPLC) technology. The beam\r\nshaping is accomplished using two integrated mirrors positioned between the collimation block and either a focusing block or\r\na scanner. MPLC technology enables highly flexible beam shaping. Notably, this technology offers a depth of field four times\r\ngreater than dual-core technologies, significantly simplifying its application.\r\nThe presentation will showcase the benefits achieved in welding real components: battery modules, busbars, and hairpins.\r\nAdditionally, an X-ray analysis of the welds will be presented. Simulations of numerous beam shapes and their effects on the\r\nwelding process will also be provided.", "venue" : "Fürth, LANE Conference", "language" : "english", "eventdate" : "18.09.2024", "bibtexKey": "gwenn2024LANE" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2c85db6eeec70a32df5cc78d514f1a36e/fzai", "tags" : [ "beam-shaping","core-ring","core-ring-intensity","full-penetration","myown","spatter","steel" ], "intraHash" : "c85db6eeec70a32df5cc78d514f1a36e", "interHash" : "9c7480eb889bc85f5fb508a237633ab1", "label" : "Effect of concentric intensity distributions on spatter formation in full penetration welding of high-alloy steels", "user" : "fzai", "description" : "", "date" : "2024-10-24 09:31:16", "changeDate" : "2024-10-24 09:31:16", "count" : 3, "pub-type": "inproceedings", "journal": "Procedia CIRP","publisher":"Elsevier BV", "year": "2024", "url": "http://dx.doi.org/10.1016/j.procir.2024.08.150", "author": [ "Christian Diegel","Klaus Schricker","Leander Schmidt","Julius Löser","Felix Zaiß","Christian Hagenlocher","Thomas Graf","Jean Pierre Bergmann" ], "authors": [ {"first" : "Christian", "last" : "Diegel"}, {"first" : "Klaus", "last" : "Schricker"}, {"first" : "Leander", "last" : "Schmidt"}, {"first" : "Julius", "last" : "Löser"}, {"first" : "Felix", "last" : "Zaiß"}, {"first" : "Christian", "last" : "Hagenlocher"}, {"first" : "Thomas", "last" : "Graf"}, {"first" : "Jean Pierre", "last" : "Bergmann"} ], "volume": "124","pages": "442\u2013447", "issn" : "2212-8271", "doi" : "10.1016/j.procir.2024.08.150", "bibtexKey": "Diegel__LANE_2024" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/211bfc7909fb76c2bfaf07d2500385f24/fzai", "tags" : [ "DESY","beam-shaping","capillary","core-ring","myown","stability" ], "intraHash" : "11bfc7909fb76c2bfaf07d2500385f24", "interHash" : "5e907e20014544857af1a31b07b976ca", "label" : "Reducing capillary depth fluctuations in high-speed laser welding of stainless steel using multi-core laser technology", "user" : "fzai", "description" : "", "date" : "2024-09-23 13:27:17", "changeDate" : "2024-10-15 13:41:44", "count" : 5, "pub-type": "presentation", "journal": "Procedia CIRP","publisher":"Elsevier BV", "year": "2024", "url": "http://dx.doi.org/10.1016/j.procir.2024.08.144", "author": [ "Felix Zaiß","Michael Haas","John Powell","Johannes Wahl","Christian Diegel","Klaus Schricker","Jean Pierre Bergmann","Marc Hummel","Christoph Spurk","Alexander Olowinsky","Felix Beckmann","Julian Moosmann","Christian Hagenlocher","Thomas Graf" ], "authors": [ {"first" : "Felix", "last" : "Zaiß"}, {"first" : "Michael", "last" : "Haas"}, {"first" : "John", "last" : "Powell"}, {"first" : "Johannes", "last" : "Wahl"}, {"first" : "Christian", "last" : "Diegel"}, {"first" : "Klaus", "last" : "Schricker"}, {"first" : "Jean Pierre", "last" : "Bergmann"}, {"first" : "Marc", "last" : "Hummel"}, {"first" : "Christoph", "last" : "Spurk"}, {"first" : "Alexander", "last" : "Olowinsky"}, {"first" : "Felix", "last" : "Beckmann"}, {"first" : "Julian", "last" : "Moosmann"}, {"first" : "Christian", "last" : "Hagenlocher"}, {"first" : "Thomas", "last" : "Graf"} ], "volume": "124","pages": "413\u2013417", "venue" : "Fürth, LANE Conference", "language" : "english", "eventdate" : "18.09.2024", "issn" : "2212-8271", "doi" : "10.1016/j.procir.2024.08.144", "bibtexKey": "Zai__2024" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/22ab87948bc06da751f475ed2c8e4ffe7/fzai", "tags" : [ "DESY","beam-shaping","capillary","core-ring","myown","peer","stability" ], "intraHash" : "2ab87948bc06da751f475ed2c8e4ffe7", "interHash" : "5e907e20014544857af1a31b07b976ca", "label" : "Reducing capillary depth fluctuations in high-speed laser welding of stainless steel using multi-core laser technology", "user" : "fzai", "description" : "", "date" : "2024-09-23 13:22:37", "changeDate" : "2024-10-19 22:59:23", "count" : 5, "pub-type": "inproceedings", "journal": "Procedia CIRP","publisher":"Elsevier BV", "year": "2024", "url": "http://dx.doi.org/10.1016/j.procir.2024.08.144", "author": [ "Felix Zaiß","Michael Haas","John Powell","Johannes Wahl","Christian Diegel","Klaus Schricker","Jean Pierre Bergmann","Marc Hummel","Christoph Spurk","Alexander Olowinsky","Felix Beckmann","Julian Moosmann","Christian Hagenlocher","Thomas Graf" ], "authors": [ {"first" : "Felix", "last" : "Zaiß"}, {"first" : "Michael", "last" : "Haas"}, {"first" : "John", "last" : "Powell"}, {"first" : "Johannes", "last" : "Wahl"}, {"first" : "Christian", "last" : "Diegel"}, {"first" : "Klaus", "last" : "Schricker"}, {"first" : "Jean Pierre", "last" : "Bergmann"}, {"first" : "Marc", "last" : "Hummel"}, {"first" : "Christoph", "last" : "Spurk"}, {"first" : "Alexander", "last" : "Olowinsky"}, {"first" : "Felix", "last" : "Beckmann"}, {"first" : "Julian", "last" : "Moosmann"}, {"first" : "Christian", "last" : "Hagenlocher"}, {"first" : "Thomas", "last" : "Graf"} ], "volume": "124","pages": "413\u2013417", "issn" : "2212-8271", "doi" : "10.1016/j.procir.2024.08.144", "bibtexKey": "Zai__2024" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/25314ae493a5c35cfed038b0622b4bcfe/fzai", "tags" : [ "beam-shaping","core-ring","formation","imaging","myown","spatter" ], "intraHash" : "5314ae493a5c35cfed038b0622b4bcfe", "interHash" : "5822bf7bf5504ecd137815fbeed61b5d", "label" : "Influence of capillary shape on spatter formation during welding with ring-core fiber systems", "user" : "fzai", "description" : "", "date" : "2024-05-08 12:04:34", "changeDate" : "2024-05-08 12:14:33", "count" : 5, "pub-type": "presentation", "year": "2023", "url": "", "author": [ "Felix Zaiß","Michael Haas","Jonas Wagner","Christian Diegel","Klaus Schricker","Jean Pierre Bergmann","Marc Hummel","Alexander Olowinsky","Felix Beckmann","Julian Moosmann","Christian Hagenlocher","Thomas Graf" ], "authors": [ {"first" : "Felix", "last" : "Zaiß"}, {"first" : "Michael", "last" : "Haas"}, {"first" : "Jonas", "last" : "Wagner"}, {"first" : "Christian", "last" : "Diegel"}, {"first" : "Klaus", "last" : "Schricker"}, {"first" : "Jean Pierre", "last" : "Bergmann"}, {"first" : "Marc", "last" : "Hummel"}, {"first" : "Alexander", "last" : "Olowinsky"}, {"first" : "Felix", "last" : "Beckmann"}, {"first" : "Julian", "last" : "Moosmann"}, {"first" : "Christian", "last" : "Hagenlocher"}, {"first" : "Thomas", "last" : "Graf"} ], "abstract": "During laser welding, the formation of spatter results from instabilities of the capillary, which are associated with adverse conditions in the melt flow surrounding the capillary and in the vapor flow at the capillary opening.\r\nA change of the characteristics of these flows in the melt pool and in the capillary requires a change of the shape of the capillary and/or the surrounding melt pool. In order to influence the stabilize the capillary the intensity distribution was varied by means of a ring-core fiber system. Analysis of the resulting welds shows a significant effect of the intensity distribution on the stability of the capillary shape and considerable changes in the melt flow direction and velocity. These findings identified an optimum capillary shape, which results from a specific power share in the ring-core fiber combination.", "eventtitle" : "Lasers in Manufacturing Conference 2023", "venue" : "Munich", "language" : "english", "eventdate" : "30.06.2023", "bibtexKey": "zaissLIM23influence" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/280484922ed9919dbe82bf0262b31a371/fzai", "tags" : [ "beam-shaping","core-ring","formation","imaging","myown","spatter","synchrotron","x-ray" ], "intraHash" : "80484922ed9919dbe82bf0262b31a371", "interHash" : "5822bf7bf5504ecd137815fbeed61b5d", "label" : "Influence of capillary shape on spatter formation during welding with ring-core fiber systems", "user" : "fzai", "description" : "", "date" : "2024-05-08 09:12:44", "changeDate" : "2024-05-08 09:12:44", "count" : 5, "pub-type": "inproceedings", "year": "2023", "url": "https://wlt.de/sites/default/files/2023-09/Contribution_268.pdf", "author": [ "Felix Zaiß","Michael Haas","Jonas Wagner","Christian Diegel","Klaus Schricker","Jean Pierre Bergmann","Marc Hummel","Alexander Olowinsky","Felix Beckmann","Julian Moosmann","Christian Hagenlocher","Thomas Graf" ], "authors": [ {"first" : "Felix", "last" : "Zaiß"}, {"first" : "Michael", "last" : "Haas"}, {"first" : "Jonas", "last" : "Wagner"}, {"first" : "Christian", "last" : "Diegel"}, {"first" : "Klaus", "last" : "Schricker"}, {"first" : "Jean Pierre", "last" : "Bergmann"}, {"first" : "Marc", "last" : "Hummel"}, {"first" : "Alexander", "last" : "Olowinsky"}, {"first" : "Felix", "last" : "Beckmann"}, {"first" : "Julian", "last" : "Moosmann"}, {"first" : "Christian", "last" : "Hagenlocher"}, {"first" : "Thomas", "last" : "Graf"} ], "volume": "Lasers in Manufacturing Conference 2023","abstract": "During laser welding, the formation of spatter results from instabilities of the capillary, which are associated with adverse conditions in the melt flow surrounding the capillary and in the vapor flow at the capillary opening.\r\nA change of the characteristics of these flows in the melt pool and in the capillary requires a change of the shape of the capillary and/or the surrounding melt pool. In order to influence the stabilize the capillary the intensity distribution was varied by means of a ring-core fiber system. Analysis of the resulting welds shows a significant effect of the intensity distribution on the stability of the capillary shape and considerable changes in the melt flow direction and velocity. These findings identified an optimum capillary shape, which results from a specific power share in the ring-core fiber combination.", "venue" : "Munich", "language" : "englisch", "bibtexKey": "zai2023influence" } ] }