@article{RungBokanKleinwortetal.2019, author = {Rung, Stefan and Bokan, Kevin and Kleinwort, Frederick and Schwarz, Simon and Simon, Peter and Klein-Wiele, Jan-Hendrik and Esen, Cemal and Hellmann, Ralf}, title = {Possibilities of Dry and Lubricated Friction Modification Enabled by Different Ultrashort Laser-Based Surface Structuring Methods}, series = {Lubricants}, volume = {7}, journal = {Lubricants}, number = {43}, doi = {10.3390/lubricants7050043}, pages = {1 -- 13}, year = {2019}, abstract = {In this contribution we report on the possibilities of dry and lubricated friction modification introduced by different laser surface texturing methods. We compare the potential of Laser-Induced Periodic Surface Structures and Laser Beam Interference Ablation on 100Cr6 steel in a linear reciprocating ball-on-disc configuration using 100Cr6 steel and tungsten carbide balls with load forces between 50mN and 1000 mN. For dry friction, we find a possibility to reduce the coefficient of friction and we observe a pronounced direction dependency for surfaces fabricated by Laser Beam Interference Ablation. Furthermore, Laser-Induced Periodic Surface Structures result in a load-dependent friction reduction for lubricated linear reciprocating movements. This work helps to identify the modification behaviour of laser generated micro structures with feature sizes of approximately 1μm and reveals new possibilities for surface engineering}, subject = {Laser}, language = {en} } @inproceedings{SchwarzRungEsenetal.2020, author = {Schwarz, Simon and Rung, Stefan and Esen, Cemal and Hellmann, Ralf}, title = {Current results on laser-based production of complex optics in glass}, series = {10. Wetzlarer Herbsttagung "Moderne Optikfertigung", 29. - 30. September 2020, Wetzlar}, booktitle = {10. Wetzlarer Herbsttagung "Moderne Optikfertigung", 29. - 30. September 2020, Wetzlar}, year = {2020}, subject = {Laserbearbeitung}, language = {en} } @inproceedings{SchwarzRungEsenetal.2020, author = {Schwarz, Simon and Rung, Stefan and Esen, Cemal and Hellmann, Ralf}, title = {UKP-Prozess mit anschließendem CO2-Laserpolieren zur Fertigung komplexer Optiken}, series = {10. Workshop Laserbearbeitung von Glaswerkstoffen}, booktitle = {10. Workshop Laserbearbeitung von Glaswerkstoffen}, year = {2020}, subject = {Linse}, language = {en} } @misc{SchwarzHellmann2021, author = {Schwarz, Simon and Hellmann, Ralf}, title = {Rapid laser fabrication of complex glass optics}, series = {International Research Days}, journal = {International Research Days}, year = {2021}, abstract = {Poster}, subject = {Laserbearbeitung}, language = {en} } @article{SchwarzRungEsenetal.2021, author = {Schwarz, Simon and Rung, Stefan and Esen, Cemal and Hellmann, Ralf}, title = {Enhanced ablation efficiency using GHz bursts in micromachining fused silica}, series = {Optics Letters}, volume = {46}, journal = {Optics Letters}, number = {2}, pages = {282 -- 285}, year = {2021}, subject = {Fr{\"a}sen}, language = {de} } @article{SchwarzGoetzendorferRungetal.2021, author = {Schwarz, Simon and G{\"o}tzendorfer, Babette and Rung, Stefan and Esen, Cemal and Hellmann, Ralf}, title = {Compact Beam Homogenizer Module with Laser-Fabricated Lens-Arrays}, series = {applied sciences}, volume = {2021}, journal = {applied sciences}, number = {11}, pages = {1018 -- 1018}, year = {2021}, subject = {Femtosekundenlaser}, language = {en} } @article{SchwarzRungEsenetal.2021, author = {Schwarz, Simon and Rung, Stefan and Esen, Cemal and Hellmann, Ralf}, title = {Ultrashort pulsed laser backside ablation of fused silica}, series = {Optics Express}, volume = {29}, journal = {Optics Express}, number = {15}, pages = {23477 -- 23486}, year = {2021}, subject = {Femtosekundenlaser}, language = {de} } @article{RungBokanRutschetal.2018, author = {Rung, Stefan and Bokan, Kevin and Rutsch, Kevin and Schwarz, Simon and Esen, Cemal and Hellmann, Ralf}, title = {Laser Induced Periodic Surface Structures on 100Cr6 Steel for Modification of Friction Demonstrated with Stribeck Test}, series = {Journal of Laser Micro/Nanoengineering}, volume = {13}, journal = {Journal of Laser Micro/Nanoengineering}, number = {3}, doi = {10.2961/jlmn.2018.03.0004}, pages = {160 -- 165}, year = {2018}, abstract = {In this contribution, we report on surface functionalization by introducing laser induced periodic surface structures on 100Cr6 bearing steel to modify complex tribological properties. The advanced approach of this study is the measurement of the coefficient of friction by performing a ball-on-disk Stribeck test on laser structured surfaces with polytetrafluoroethylene balls in a lubricant environment. The Stribeck test reveals the modified friction behavior using translation speeds up to 106 mm/min and load forces between 100 mN and 5000 mN. Our results show increased stiction and coefficient of friction for laser structured surfaces in the regime of boundary lubrication which is attributed to the laser induced surface asperities. Decreased coefficient of friction is observed in the regime of mixed and hydrodynamic lubrication, i.e. for velocities higher than 1000 mm/min, for surfaces covered by laser induced periodic surface structures with low spatial frequency.}, subject = {Laser}, language = {en} } @article{SchwarzRungHellmann2016, author = {Schwarz, Simon and Rung, Stefan and Hellmann, Ralf}, title = {Generation of laser-induced periodic surface structures on transparent material-fused silica}, series = {Applied Physics Letters}, volume = {108}, journal = {Applied Physics Letters}, number = {18}, pages = {181607 -- 181607}, year = {2016}, subject = {Laser}, language = {en} } @article{SchwarzRungEsenetal.2018, author = {Schwarz, Simon and Rung, Stefan and Esen, Cemal and Hellmann, Ralf}, title = {Fabrication of a high-quality axicon by femtosecond laser ablation and CO2 laser polishing for quasi-Bessel beam generation}, series = {Optics Express}, volume = {26}, journal = {Optics Express}, number = {18}, pages = {23287 -- 23294}, year = {2018}, subject = {Femtosekundenlaser}, language = {en} } @article{SchwarzRungHellmann2017, author = {Schwarz, Simon and Rung, Stefan and Hellmann, Ralf}, title = {One-dimensional low spatial frequency LIPSS with rotating orientation on fused silica}, series = {Applied Surface Science}, volume = {2017}, journal = {Applied Surface Science}, number = {411}, pages = {113 -- 116}, year = {2017}, subject = {Quarzglas}, language = {en} }