@article{AbbasBalcBremenetal.2022,
  author    = {Abbas, Karim and Balc, Nicolae and Bremen, Sebastian and Skupin, Marco},
  title     = {Crystallization and aging behavior of polyetheretherketone PEEK within rapid tooling and rubber molding},
  series = {Journal of Manufacturing and Materials Processing},
  volume    = {6},
  journal   = {Journal of Manufacturing and Materials Processing},
  number    = {5},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2504-4494},
  doi       = {10.3390/jmmp6050093},
  pages     = {1 -- 12},
  year      = {2022},
  abstract  = {In times of short product life cycles, additive manufacturing and rapid tooling are important methods to make tool development and manufacturing more efficient. High-performance polymers are the key to mold production for prototypes and small series. However, the high temperatures during vulcanization injection molding cause thermal aging and can impair service life. The extent to which the thermal stress over the entire process chain stresses the material and whether it leads to irreversible material aging is evaluated. To this end, a mold made of PEEK is fabricated using fused filament fabrication and examined for its potential application. The mold is heated to 200 ◦C, filled with rubber, and cured. A differential scanning calorimetry analysis of each process step illustrates the crystallization behavior and first indicates the material resistance. It shows distinct cold crystallization regions at a build chamber temperature of 90 ◦C. At an ambient temperature above Tg, crystallization of 30\% is achieved, and cold crystallization no longer occurs. Additional tensile tests show a decrease in tensile strength after ten days of thermal aging. The steady decrease in recrystallization temperature indicates degradation of the additives. However, the tensile tests reveal steady embrittlement of the material due to increasing crosslinking.},
  language  = {en}
}
@article{AbbasHedwigBalcetal.2023,
  author    = {Abbas, Karim and Hedwig, Lukas and Balc, Nicolae and Bremen, Sebastian},
  title     = {Advanced FFF of PEEK: Infill strategies and material characteristics for rapid tooling},
  series = {Polymers},
  volume    = {2023},
  journal   = {Polymers},
  number    = {15},
  publisher = {MDPI},
  address   = {Basel},
  doi       = {10.3390/polym15214293},
  pages     = {Artikel 4293},
  year      = {2023},
  abstract  = {Traditional vulcanization mold manufacturing is complex, costly, and under pressure due to shorter product lifecycles and diverse variations. Additive manufacturing using Fused Filament Fabrication and high-performance polymers like PEEK offer a promising future in this industry. This study assesses the compressive strength of various infill structures (honeycomb, grid, triangle, cubic, and gyroid) when considering two distinct build directions (Z, XY) to enhance PEEK's economic and resource efficiency in rapid tooling. A comparison with PETG samples shows the behavior of the infill strategies. Additionally, a proof of concept illustrates the application of a PEEK mold in vulcanization. A peak compressive strength of 135.6 MPa was attained in specimens that were 100\% solid and subjected to thermal post-treatment. This corresponds to a 20\% strength improvement in the Z direction. In terms of time and mechanical properties, the anisotropic grid and isotropic cubic infill have emerged for use in rapid tooling. Furthermore, the study highlights that reducing the layer thickness from 0.15 mm to 0.1 mm can result in a 15\% strength increase. The study unveils the successful utilization of a room-temperature FFF-printed PEEK mold in vulcanization injection molding. The parameters and infill strategies identified in this research enable the resource-efficient FFF printing of PEEK without compromising its strength properties. Using PEEK in rapid tooling allows a cost reduction of up to 70\% in tool production.},
  language  = {en}
}
@article{AbdelLatifPeekenBenner1985,
  author    = {Abdel-Latif, Lotfie Ahmed and Peeken, Heinz and Benner, Joachim},
  title     = {Thermohydrodynamic analysis of thrust-bearing with circular pads running on bubbly oil (BTHD-theory)},
  series = {Journal of tribology},
  volume    = {107},
  journal   = {Journal of tribology},
  number    = {4},
  isbn      = {0742-4787},
  issn      = {1528-8897},
  pages     = {527 -- 537},
  year      = {1985},
  language  = {en}
}
@article{AhmedReisgenSchleseretal.2010,
  author    = {Ahmed, Essam and Reisgen, Uwe and Schleser, Markus and Mokrov, Oleg},
  title     = {On formability of tailor laser welded blanks of DP/TRIP steel sheets},
  series = {Science and technology of welding and joining},
  volume    = {15},
  journal   = {Science and technology of welding and joining},
  number    = {5},
  publisher = {Maney},
  address   = {Leeds},
  issn      = {1743-2936},
  doi       = {10.1179/136217110X12731414739754},
  pages     = {337 -- 342},
  year      = {2010},
  abstract  = {This paper aims to evaluate the formability of tailor welded blanks of dual phase (DP600)/transformation induced plasticity (TRIP700) steel sheets. In this work, bead on plate butt joints of 2·5 mm DP600 and 1·2 mm TRIP700 steel sheets were performed using CO2 laser beam welding. Microhardness measurements and transverse tensile testing were carried out to characterise the welds. The formability of base metals and welds were investigated by standard Erichsen test. In a perpendicular tensile test to the weld line, all specimens were fractured at the TRIP base metal, and the strengths were somewhat higher than those of base metal. There was a significant reduction in formability caused by welding of the DP600/TRIP700 steel sheets, and the formability increased with increasing welding speed.},
  language  = {en}
}
@article{AnikFrohberg1984,
  author    = {Anik, Sabri and Frohberg, Martin G.},
  title     = {Thermodynamics and solubility of oxygen in liquid copper-lead alloys at 1200°C from E.M.F. measurements},
  series = {Berichte der Bunsengesellschaft f{\"u}r physikalische Chemie},
  volume    = {88},
  journal   = {Berichte der Bunsengesellschaft f{\"u}r physikalische Chemie},
  number    = {8},
  issn      = {0940-483X},
  pages     = {707 -- 710},
  year      = {1984},
  language  = {en}
}
@article{AnikFrohberg1987,
  author    = {Anik, Sabri and Frohberg, Martin G.},
  title     = {Thermodynamics and solubility of oxygen in liquid bismuth-lead and bismuth-antimony alloys},
  series = {Berichte der Bunsengesellschaft f{\"u}r physikalische Chemie},
  volume    = {91},
  journal   = {Berichte der Bunsengesellschaft f{\"u}r physikalische Chemie},
  number    = {7},
  issn      = {0940-483X},
  pages     = {790 -- 794},
  year      = {1987},
  language  = {en}
}
@article{AnikFrohberg1984,
  author    = {Anik, Sabri and Frohberg, Martin G.},
  title     = {Investigations of the thermodynamics of oxygen and the determination of the miscibility gap in the system copper-oxygen-lead at 12000C},
  series = {Zeitschrift f{\"u}r Metallkunde},
  volume    = {75},
  journal   = {Zeitschrift f{\"u}r Metallkunde},
  number    = {8},
  issn      = {0044-3093},
  pages     = {586 -- 589},
  year      = {1984},
  language  = {en}
}
@article{AnikFrohberg1983,
  author    = {Anik, Sabri and Frohberg, Martin G.},
  title     = {Investigation of the thermodynamics of oxygen and the determination of phase boundaries in the system copper-oxygen-bismuth at 12000C},
  series = {Zeitschrift f{\"u}r Metallkunde},
  volume    = {74},
  journal   = {Zeitschrift f{\"u}r Metallkunde},
  number    = {8},
  issn      = {0044-3093},
  pages     = {530 -- 534},
  year      = {1983},
  language  = {en}
}
@article{AnikFrohberg1988,
  author    = {Anik, Sabri and Frohberg, Martin G.},
  title     = {Thermodynamics of oxygen in the copper-antimony system at 1473K},
  series = {Erzmetall : Rohstoffgewinnung, Verarbeitung, Recycling, Umwelttechnik},
  volume    = {41},
  journal   = {Erzmetall : Rohstoffgewinnung, Verarbeitung, Recycling, Umwelttechnik},
  number    = {10},
  issn      = {0044-2658},
  pages     = {498 -- 501},
  year      = {1988},
  language  = {en}
}
@article{AnikFrohbergKapoor1983,
  author    = {Anik, Sabri and Frohberg, Martin G. and Kapoor, Madan Lal},
  title     = {Experiments and theoretical considerations on the solution of oxygen in binary metal alloys},
  series = {Berichte der Bunsengesellschaft f{\"u}r physikalische Chemie},
  volume    = {87},
  journal   = {Berichte der Bunsengesellschaft f{\"u}r physikalische Chemie},
  number    = {12},
  issn      = {0005-9021},
  pages     = {1201 -- 1204},
  year      = {1983},
  language  = {en}
}
@article{AnikFrohbergKapoor1983,
  author    = {Anik, Sabri and Frohberg, Martin G. and Kapoor, Madan Lal},
  title     = {Prediction of thermodynamic properties of oxygen in binary metallic solvents},
  series = {Zeitschrift f{\"u}r Metallkunde},
  volume    = {74},
  journal   = {Zeitschrift f{\"u}r Metallkunde},
  number    = {6},
  issn      = {0044-3093},
  pages     = {372 -- 375},
  year      = {1983},
  language  = {en}
}
@article{AnikKapoorFrohberg1983,
  author    = {Anik, Sabri and Kapoor, Madan Lal and Frohberg, Martin G.},
  title     = {Thermodynamic behaviour of oxygen in molten substitutional alloy solvents},
  series = {Zeitschrift f{\"u}r Metallkunde},
  volume    = {74},
  journal   = {Zeitschrift f{\"u}r Metallkunde},
  number    = {1},
  issn      = {0044-3093},
  pages     = {53 -- 58},
  year      = {1983},
  language  = {en}
}
@article{BeckenbachScheidweiler2016,
  author    = {Beckenbach, Isabel and Scheidweiler, Robert},
  title     = {Perfect ƒ-Matchings and ƒ-Factors in Hypergraphs - A Combinatorial Approach},
  series = {Discrete Mathematics},
  volume    = {240},
  journal   = {Discrete Mathematics},
  number    = {10},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {2192-7782},
  doi       = {10.1016/j.disc.2017.05.005},
  pages     = {2499 -- 2506},
  year      = {2016},
  abstract  = {We prove characterizations of the existence of perfect ƒ-matchings in uniform mengerian and perfect hypergraphs. Moreover, we investigate the ƒ-factor problem in balanced hypergraphs. For uniform balanced hypergraphs we prove two existence theorems with purely combinatorial arguments, whereas for non-uniform balanced hypergraphs we show that the ƒ-factor problem is NP-hard.},
  language  = {en}
}
@article{BraunChengDoweyetal.2021,
  author    = {Braun, Sebastian and Cheng, Chi-Tsun and Dowey, Steve and Wollert, J{\"o}rg},
  title     = {Performance evaluation of skill-based order-assignment in production environments with multi-agent systems},
  series = {IEEE Journal of Emerging and Selected Topics in Industrial Electronics},
  journal   = {IEEE Journal of Emerging and Selected Topics in Industrial Electronics},
  number    = {Early Access},
  publisher = {IEEE},
  address   = {New York},
  issn      = {2687-9735},
  doi       = {10.1109/JESTIE.2021.3108524},
  year      = {2021},
  abstract  = {The fourth industrial revolution introduces disruptive technologies to production environments. One of these technologies are multi-agent systems (MASs), where agents virtualize machines. However, the agent's actual performances in production environments can hardly be estimated as most research has been focusing on isolated projects and specific scenarios. We address this gap by implementing a highly connected and configurable reference model with quantifiable key performance indicators (KPIs) for production scheduling and routing in single-piece workflows. Furthermore, we propose an algorithm to optimize the search of extrema in highly connected distributed systems. The benefits, limits, and drawbacks of MASs and their performances are evaluated extensively by event-based simulations against the introduced model, which acts as a benchmark. Even though the performance of the proposed MAS is, on average, slightly lower than the reference system, the increased flexibility allows it to find new solutions and deliver improved factory-planning outcomes. Our MAS shows an emerging behavior by using flexible production techniques to correct errors and compensate for bottlenecks. This increased flexibility offers substantial improvement potential. The general model in this paper allows the transfer of the results to estimate real systems or other models.},
  language  = {en}
}
@article{BucurLazarescuPopetal.2019,
  author    = {Bucur, Alexandru and Lazarescu, Lucian and Pop, Grigore Marian and Achimas, Gheorghe and Gebhardt, Andreas},
  title     = {Tribological performance of biodegradable lubricants under different surface roughness of tools},
  series = {Academic Journal of Manufacturing Engineering},
  volume    = {17},
  journal   = {Academic Journal of Manufacturing Engineering},
  number    = {1},
  issn      = {1583-7904},
  pages     = {172 -- 178},
  year      = {2019},
  language  = {en}
}
@article{CosmaKesslerGebhardtetal.2020,
  author    = {Cosma, Cosmin and Kessler, Julia and Gebhardt, Andreas and Campbell, Ian and Balc, Nicolae},
  title     = {Improving the Mechanical Strength of Dental Applications and Lattice Structures SLM Processed},
  series = {Materials},
  volume    = {13},
  journal   = {Materials},
  number    = {4},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {1996-1944},
  doi       = {10.3390/ma13040905},
  pages     = {1 -- 18},
  year      = {2020},
  abstract  = {To manufacture custom medical parts or scaffolds with reduced defects and high mechanical characteristics, new research on optimizing the selective laser melting (SLM) parameters are needed. In this work, a biocompatible powder, 316L stainless steel, is characterized to understand the particle size, distribution, shape and flowability. Examination revealed that the 316L particles are smooth, nearly spherical, their mean diameter is 39.09 μm and just 10\% of them hold a diameter less than 21.18 μm. SLM parameters under consideration include laser power up to 200 W, 250-1500 mm/s scanning speed, 80 μm hatch spacing, 35 μm layer thickness and a preheated platform. The effect of these on processability is evaluated. More than 100 samples are SLM-manufactured with different process parameters. The tensile results show that is possible to raise the ultimate tensile strength up to 840 MPa, adapting the SLM parameters for a stable processability, avoiding the technological defects caused by residual stress. Correlating with other recent studies on SLM technology, the tensile strength is 20\% improved. To validate the SLM parameters and conditions established, complex bioengineering applications such as dental bridges and macro-porous grafts are SLM-processed, demonstrating the potential to manufacture medical products with increased mechanical resistance made of 316L.},
  language  = {en}
}
@article{DiltheyBrandenburgSchleser2004,
  author    = {Dilthey, Ulrich and Brandenburg, Annette and Schleser, Markus},
  title     = {Dispensing and application of unfilled adhesives in the micro range},
  series = {Welding and cutting. 3 (2004), H. 4},
  journal   = {Welding and cutting. 3 (2004), H. 4},
  issn      = {1612-3433},
  pages     = {250 -- 254},
  year      = {2004},
  language  = {en}
}
@article{DiltheySchleserFeldmannetal.2008,
  author    = {Dilthey, Ulrich and Schleser, Markus and Feldmann, Martin and Pak, Daniel and Geßler, Achim},
  title     = {Investigation of punctiform, plane and hybrid joints of textile-reinforced concrete parts},
  series = {Cement and concrete composites},
  volume    = {Vol. 30},
  journal   = {Cement and concrete composites},
  number    = {iss. 2},
  issn      = {0958-9465},
  pages     = {82 -- 87},
  year      = {2008},
  language  = {en}
}
@article{DuesGebhardtKallweitetal.1994,
  author    = {Dues, M. and Gebhardt, Andreas and Kallweit, Stephan and Scheffler, T. and Siekmann, H. and Uchiyama, T.},
  title     = {Flow Visualization in a Cavitating Flow},
  series = {Proceedings of the German-Japanese Symposium on Multi-Phase Flow : Karlsruhe, Germany, August 23 - 25, 1994 / comp. by U. M{\"u}ller ...},
  journal   = {Proceedings of the German-Japanese Symposium on Multi-Phase Flow : Karlsruhe, Germany, August 23 - 25, 1994 / comp. by U. M{\"u}ller ...},
  publisher = {Kernforschungszentrum Karlsruhe},
  address   = {Karlsruhe},
  pages     = {391 -- 402},
  year      = {1994},
  language  = {en}
}
@article{EngemannCoenenDawaretal.2021,
  author    = {Engemann, Heiko and C{\"o}nen, Patrick and Dawar, Harshal and Du, Shengzhi and Kallweit, Stephan},
  title     = {A robot-assisted large-scale inspection of wind turbine blades in manufacturing using an autonomous mobile manipulator},
  series = {Applied Sciences},
  volume    = {11},
  journal   = {Applied Sciences},
  number    = {19},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {2076-3417},
  doi       = {10.3390/app11199271},
  pages     = {1 -- 22},
  year      = {2021},
  abstract  = {Wind energy represents the dominant share of renewable energies. The rotor blades of a wind turbine are typically made from composite material, which withstands high forces during rotation. The huge dimensions of the rotor blades complicate the inspection processes in manufacturing. The automation of inspection processes has a great potential to increase the overall productivity and to create a consistent reliable database for each individual rotor blade. The focus of this paper is set on the process of rotor blade inspection automation by utilizing an autonomous mobile manipulator. The main innovations include a novel path planning strategy for zone-based navigation, which enables an intuitive right-hand or left-hand driving behavior in a shared human-robot workspace. In addition, we introduce a new method for surface orthogonal motion planning in connection with large-scale structures. An overall execution strategy controls the navigation and manipulation processes of the long-running inspection task. The implemented concepts are evaluated in simulation and applied in a real-use case including the tip of a rotor blade form.},
  language  = {en}
}