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    <id>64161</id>
    <completedYear/>
    <publishedYear>2025</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
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    <volume/>
    <type>poster</type>
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    <belongsToBibliography>0</belongsToBibliography>
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    <title language="eng">Component-test for determination of welding residual stresses and their effect on stress relief cracking in thick-walled welds</title>
    <abstract language="eng">Controlling the residual stress level during welding of creep-resistant Cr-Mo-V steels is crucial to avoid so called stress relief cracking (SRC) during post weld heat treatment (PWHT) of large-scale components. In the present study, a laboratory scale test specimen (slotted sample with 400 mm width, 400 mm length and 25 mm thickness) was used to simulate thick-walled component welds made of 13CrMoV9-10. The aim was to identify the level and distribution of residual stresses to evaluate the suitability of the specimen for laboratory based SRC testing. High restraint was ensured by the specimen geometry with a narrow welding gap in the center. This gap was filled by multi-layer submerged arc welding. Two specimens were welded with identical parameters and compared in the as-welded state and after PWHT (705 °C for 10 h). Neutron diffraction was used to determine the residual stresses in the weld metal, the heat-affected zone (HAZ) and the base material at different depths longitudinal, transverse, and normal to the welding direction. The experiments were performed on the former instrument E3 of the research reactor BER II of Helmholtz-Zentrum Berlin (HZB), Germany. Complementarily, laboratory X-ray diffraction was applied to characterize the surface residual stresses. In the welded condition, especially in the weld metal and the adjacent HAZ, the longitudinal residual stresses reached values of up to 1,000 MPa to 1,200 MPa due to the increasing strength and hardness of the CrMoV-material during welding. The conducted welding experiments revealed that way higher residual stresses in the welded joint have to anticipated before the PWHT is performed than it was expected in advance. This demonstrated the necessity of suitable component-like welding tests as they must ensure realistic mechanical stiffness (hindered shrinkage of welding joint by slotted self-restraint sample) and heat dissipation conditions (definition of minimum welding joint thickness vs. welding process-specific heat input).</abstract>
    <enrichment key="eventName">FEMS Euromat 2025 - 18th European Congress and Exhibition on Advanced Materials and Processes</enrichment>
    <enrichment key="eventPlace">Granada, Spain</enrichment>
    <enrichment key="eventStart">15.09.2025</enrichment>
    <enrichment key="eventEnd">18.09.2025</enrichment>
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    <author>Michael Rhode</author>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Component test</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Submerged arc welding</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Post weld heat treatment</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Residual stresses</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Neutron diffraction</value>
    </subject>
    <collection role="ddc" number="620">Ingenieurwissenschaften und zugeordnete Tätigkeiten</collection>
    <collection role="institutes" number="">9 Komponentensicherheit</collection>
    <collection role="institutes" number="">9.3 Schweißtechnische Fertigungsverfahren</collection>
    <collection role="institutes" number="">9.4 Integrität von Schweißverbindungen</collection>
    <collection role="themenfelder" number="">Material</collection>
    <collection role="themenfelder" number="">Degradationsmechanismen</collection>
    <collection role="fulltextaccess" number="">Datei im Netzwerk der BAM verfügbar ("Closed Access")</collection>
    <collection role="literaturgattung" number="">Präsentation</collection>
  </doc>
  <doc>
    <id>63067</id>
    <completedYear/>
    <publishedYear>2025</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>lecture</type>
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    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
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    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Project summary: Impact of manufacturing process related residual stresses in wound composite material on the operational safety of hydrogen pressure vessels</title>
    <abstract language="eng">This presentation is a summary of a doctoral project within the BTU-BAM Graduate School 'Trustworthy Hydrogen'. The results of both theoretical and experimental investigations are presented and discussed.</abstract>
    <enrichment key="eventName">Summer School 2025 - BTU-BAM Graduate School "Trustworthy Hydrogen"</enrichment>
    <enrichment key="eventPlace">Berlin, Germany</enrichment>
    <enrichment key="eventStart">05.07.2025</enrichment>
    <enrichment key="eventEnd">07.05.2025</enrichment>
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    <author>Bartosz Popiela</author>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Composite</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Pressure vessel</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Residual stresses</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Burst test</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Filament winding</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Carbon fiber</value>
    </subject>
    <collection role="ddc" number="621">Angewandte Physik</collection>
    <collection role="institutes" number="">3 Gefahrgutumschließungen; Energiespeicher</collection>
    <collection role="themenfelder" number="">Energie</collection>
    <collection role="fulltextaccess" number="">Datei im Netzwerk der BAM verfügbar ("Closed Access")</collection>
    <collection role="literaturgattung" number="">Präsentation</collection>
    <collection role="institutes" number="">3.5 Sicherheit von Gasspeichern und Gefahrguttanks</collection>
    <collection role="themenfelder" number="">Wasserstoff</collection>
  </doc>
  <doc>
    <id>61779</id>
    <completedYear/>
    <publishedYear>2024</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>lecture</type>
    <publisherName/>
    <publisherPlace/>
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    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">BAM 3.5 and Trustworthy Hydrogen: Experimental Investigation of Type 4 Composite Pressure Vessels</title>
    <abstract language="eng">The presentation provided a brief introduction to Division 3.5 at BAM and detailed an experimental study of composite pressure vessels as part of the 'Trustworthy Hydrogen' project. It included an in-depth analysis of slow burst test evaluations.</abstract>
    <enrichment key="eventName">Lab Seminar of IDIM SNU</enrichment>
    <enrichment key="eventPlace">Seoul, South Korea</enrichment>
    <enrichment key="eventStart">26.11.2024</enrichment>
    <enrichment key="InvitedTalks">1</enrichment>
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    <author>Bartosz Popiela</author>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Composite</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Pressure vessel</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Residual stresses</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Burst test</value>
    </subject>
    <collection role="ddc" number="621">Angewandte Physik</collection>
    <collection role="institutes" number="">3 Gefahrgutumschließungen; Energiespeicher</collection>
    <collection role="themenfelder" number="">Energie</collection>
    <collection role="fulltextaccess" number="">Datei im Netzwerk der BAM verfügbar ("Closed Access")</collection>
    <collection role="literaturgattung" number="">Präsentation</collection>
    <collection role="institutes" number="">3.5 Sicherheit von Gasspeichern und Gefahrguttanks</collection>
    <collection role="themenfelder" number="">Wasserstoff</collection>
  </doc>
  <doc>
    <id>61734</id>
    <completedYear/>
    <publishedYear>2024</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>lecture</type>
    <publisherName/>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Performance of Type 4 Composite Pressure Vessels: Impact of Residual Stress State</title>
    <abstract language="eng">This presentation summarizes the results of an experimental study on slow burst tests, involving two pressure vessel designs with different residual stress states. The significant performance differences between the two designs highlight the critical role of residual stress state in filament-wound structures</abstract>
    <enrichment key="eventName">Composites Research Seminar at the Innovative Design and Integrated Manufacturing Lab, Seoul National University</enrichment>
    <enrichment key="eventPlace">Seoul, South Korea</enrichment>
    <enrichment key="eventStart">22.11.2024</enrichment>
    <enrichment key="InvitedTalks">1</enrichment>
    <enrichment key="opus.source">publish</enrichment>
    <enrichment key="opus.doi.autoCreate">false</enrichment>
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    <author>Bartosz Popiela</author>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Composite</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Pressure vessel</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Residual stresses</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Burst test</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Filament winding</value>
    </subject>
    <collection role="ddc" number="621">Angewandte Physik</collection>
    <collection role="institutes" number="">3 Gefahrgutumschließungen; Energiespeicher</collection>
    <collection role="themenfelder" number="">Energie</collection>
    <collection role="fulltextaccess" number="">Datei im Netzwerk der BAM verfügbar ("Closed Access")</collection>
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    <collection role="institutes" number="">3.5 Sicherheit von Gasspeichern und Gefahrguttanks</collection>
    <collection role="themenfelder" number="">Wasserstoff</collection>
  </doc>
  <doc>
    <id>61272</id>
    <completedYear/>
    <publishedYear>2024</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>lecture</type>
    <publisherName/>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Experimental study on the impact of manufacturing process related residual stresses in wound composite material on the operational safety of H2 pressure vessels</title>
    <abstract language="eng">The presentation is an update on the progress of the PhD Project. It focuses on the experimental investigation of the impact of residual stresses on the reliability of type 4 composite pressure vessels.</abstract>
    <enrichment key="eventName">Summer School 2024 - BTU-BAM Graduate School "Trustworthy Hydrogen"</enrichment>
    <enrichment key="eventPlace">Cottbus, Germany</enrichment>
    <enrichment key="eventStart">07.10.2024</enrichment>
    <enrichment key="eventEnd">11.10.2024</enrichment>
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    <author>Bartosz Popiela</author>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Composite</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Pressure vessel</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Residual stresses</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Burst test</value>
    </subject>
    <collection role="ddc" number="621">Angewandte Physik</collection>
    <collection role="institutes" number="">3 Gefahrgutumschließungen; Energiespeicher</collection>
    <collection role="themenfelder" number="">Energie</collection>
    <collection role="fulltextaccess" number="">Datei im Netzwerk der BAM verfügbar ("Closed Access")</collection>
    <collection role="literaturgattung" number="">Präsentation</collection>
    <collection role="institutes" number="">3.5 Sicherheit von Gasspeichern und Gefahrguttanks</collection>
    <collection role="themenfelder" number="">Wasserstoff</collection>
  </doc>
  <doc>
    <id>59779</id>
    <completedYear/>
    <publishedYear>2024</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst>445</pageFirst>
    <pageLast>450</pageLast>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume>2024</volume>
    <type>conferenceobject</type>
    <publisherName>Hydrogen Europe Research, BE-HyFE</publisherName>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Modelling of the Manufacturing Process Related Residual Stresses in Type 4 Pressure Vessels for Hydrogen Storage</title>
    <abstract language="eng">The publication is an extended abstract on the modelling of the manufacturing process related residual stresses in type 4 pressure vessels for hydrogen storage. A 2D analytical model based on the classical laminate theory and a 3D finite element model are introduced. The calculated residual stress state after the filament winding process as well as the stress state in service are presented and discussed.</abstract>
    <parentTitle language="eng">EPHyC2024: European PhD Hydrogen Conference, Book of Abstracts</parentTitle>
    <enrichment key="eventName">European PhD Hydrogen Conference 2024 (EPHyC2024)</enrichment>
    <enrichment key="eventPlace">Ghent, Belgium</enrichment>
    <enrichment key="eventStart">20.03.2024</enrichment>
    <enrichment key="eventEnd">22.03.2024</enrichment>
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    <author>Bartosz Popiela</author>
    <author>Stephan Günzel</author>
    <author>Georg W. Mair</author>
    <author>Holger Seidlitz</author>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Composite</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Hydrogen</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Pressure vessel</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Residual stresses</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Filament winding</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Carbon fiber</value>
    </subject>
    <collection role="ddc" number="621">Angewandte Physik</collection>
    <collection role="institutes" number="">3 Gefahrgutumschließungen; Energiespeicher</collection>
    <collection role="themenfelder" number="">Energie</collection>
    <collection role="fulltextaccess" number="">Datei im Netzwerk der BAM verfügbar ("Closed Access")</collection>
    <collection role="literaturgattung" number="">Graue Literatur</collection>
    <collection role="institutes" number="">3.5 Sicherheit von Gasspeichern und Gefahrguttanks</collection>
    <collection role="themenfelder" number="">Wasserstoff</collection>
  </doc>
  <doc>
    <id>59757</id>
    <completedYear/>
    <publishedYear>2024</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>lecture</type>
    <publisherName/>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Modelling of the manufacturing related residual stresses in type 4 pressure vessels for hydrogen storage</title>
    <abstract language="eng">Presentation about modelling of the residual stresses in type 4 pressure vessels for hydrogen storage at the European PhD Hydrogen Conference 2024 in Ghent, Belgium.</abstract>
    <enrichment key="eventName">European PhD Hydrogen Conference 2024 (EPHyC2024)</enrichment>
    <enrichment key="eventPlace">Ghent, Belgium</enrichment>
    <enrichment key="eventStart">20.03.2024</enrichment>
    <enrichment key="eventEnd">22.03.2024</enrichment>
    <enrichment key="InvitedTalks">0</enrichment>
    <enrichment key="opus.source">publish</enrichment>
    <enrichment key="opus.doi.autoCreate">false</enrichment>
    <enrichment key="opus.urn.autoCreate">true</enrichment>
    <author>Bartosz Popiela</author>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Composite</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Pressure vessel</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Residual stresses</value>
    </subject>
    <collection role="ddc" number="621">Angewandte Physik</collection>
    <collection role="institutes" number="">3 Gefahrgutumschließungen; Energiespeicher</collection>
    <collection role="themenfelder" number="">Energie</collection>
    <collection role="fulltextaccess" number="">Datei im Netzwerk der BAM verfügbar ("Closed Access")</collection>
    <collection role="literaturgattung" number="">Präsentation</collection>
    <collection role="institutes" number="">3.5 Sicherheit von Gasspeichern und Gefahrguttanks</collection>
    <collection role="themenfelder" number="">Wasserstoff</collection>
  </doc>
  <doc>
    <id>59254</id>
    <completedYear/>
    <publishedYear>2023</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>lecture</type>
    <publisherName/>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Stresses in repair welding of high-strength steels Part 2: Heat Control and Stress Optimization</title>
    <abstract language="eng">In welding of high-strength steels, e.g., for foundations and erection structures of wind energy plants, unacceptable defects can occasionally be found in the weld area, which should be removed by thermal gouging and subsequent re-welding. High shrinkage restraint of repair welds may lead to crack formation and component failure, particularly in interaction with degraded microstructures and mechanical properties due to repair cycles. This study aims for elaboration of recommendations for repair concepts appropriate to the stresses and materials involved to avoid cold cracking, damage and expensive reworking. In part 1 [1] of this study systematic investigations of influences of shrinkage restraint on residual stresses and cold cracking risk during repair welding of two high-strength steels S500MLO for offshore application and S960QL for mobile crane structures were focussed. In this part 2, the microstructure and residual stresses due to gouging and influences of heat control parameters in repair welding are analysed. A clear reduction in residual stress after gouging can be observed, especially for the specimens with restrained transverse shrinkage. Gouging to a depth of approx. 2/3 of the seam height does not lead to a complete relaxation of the observed reaction forces. Particularly for the higher strength steel S960QL, there are pronounced areas influenced by the gouging process in which a degradation of the microstructure and properties should be assumed. Overall, the repair welds show a significant increase in the width of the weld and HAZ compared to the original weld, especially in the case of S960QL/G89. The repair welds show higher welding-induced stresses than the original welds, especially in the areas of the HAZ and the base metal close to the weld seam. This behaviour can be attributed overall to increased restraint conditions due to the remaining root weld or shorter gouge grooves. In good agreement with earlier investigations, the residual stresses transverse to the weld can be significantly reduced by upwardly limited working or interpass temperatures and the reaction stresses resulting from high restraint conditions can be effectively counteracted. The influence of the heat input on the stress formation is low compared to the interpass temperature for both test materials.</abstract>
    <enrichment key="eventName">IIW Annual Assembly 2023</enrichment>
    <enrichment key="eventPlace">Singapore</enrichment>
    <enrichment key="eventStart">16.07.2023</enrichment>
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    <author>Julien Witte</author>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Repair-welding</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>High-strength steels</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Cold cracking</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Residual stresses</value>
    </subject>
    <collection role="ddc" number="620">Ingenieurwissenschaften und zugeordnete Tätigkeiten</collection>
    <collection role="institutes" number="">9 Komponentensicherheit</collection>
    <collection role="institutes" number="">9.2 Versuchsanlagen und Prüftechnik</collection>
    <collection role="institutes" number="">9.4 Integrität von Schweißverbindungen</collection>
    <collection role="themenfelder" number="">Energie</collection>
    <collection role="themenfelder" number="">Material</collection>
    <collection role="themenfelder" number="">Degradationsmechanismen</collection>
    <collection role="fulltextaccess" number="">Datei im Netzwerk der BAM verfügbar ("Closed Access")</collection>
    <collection role="literaturgattung" number="">Präsentation</collection>
  </doc>
  <doc>
    <id>59253</id>
    <completedYear/>
    <publishedYear>2023</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>lecture</type>
    <publisherName/>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Stresses in repair welding of high-strength steels Part 1: Restraint and Cold cracking risk</title>
    <abstract language="eng">The sustainable and resource-efficient production of wind energy plants requires the use of modern high-strength fine-grain structural steels. This applies to both foundation and erection structures, like mobile or ship cranes. During the assembly of steel structures, unacceptable defects can occasionally be found in the weld area. In most cases, the economical solution would be local thermal gouging of the affected areas and re-welding. Due to the high shrinkage restraint of the joint groove in the overall structure, the superposition of global and local welding-induced stresses may lead to crack formation and component failure, particularly in interaction with the degradation of the microstructure and mechanical properties of high-strength steels during the repair process. However, manufacturers hardly have any information about these issues and there is a lack of recommendations and guidelines to take these safety-relevant aspects into account in adequate repair concepts. The aim of this research is to derive recommendations for repair concepts appropriate to the stresses and materials involved providing a basis for standards and guidelines to avoid cold cracking, damage and expensive reworking especially for high-strength steels. Part 1 of this study involves systematic investigations of influences of shrinkage restraint during repair welding of two high-strength steels S500MLO for offshore application and S960QL for mobile crane structures. The quantification of the shrinkage restraint of repair weld joints was achieved by means of experimental and numerical restraint intensity analysis. In welding experiments with self-restrained slot specimens, restraint intensity and introduction of hydrogen via the welding arc using anti spatter spray were varied systematically to analyse the effect on welding result, residual stresses, and cold cracking. It could be shown that increasing restraint intensities result in significantly higher transverse residual stress levels. In the case of hydrogen introduction S500MLO showed no cold cracking independent of the restraint conditions. However, S960QL was found to be considerably cold cracking sensitive if hydrogen is introduced. With increasing restraint intensity length and number of cold cracks increases significantly. Part 2 [1] of this study is focussed on microstructure and residual stresses due to gouging and stress optimization via adequate heat control parameters in repair welding.</abstract>
    <enrichment key="eventName">IIW Annual Assembly 2023</enrichment>
    <enrichment key="eventPlace">Singapore</enrichment>
    <enrichment key="eventStart">16.07.2023</enrichment>
    <enrichment key="eventEnd">21.07.2023</enrichment>
    <enrichment key="opus.source">publish</enrichment>
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    <enrichment key="InvitedTalks">0</enrichment>
    <author>Dirk Schröpfer</author>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Repair-welding</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>MAG welding</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>High-strength steels</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Cold cracking</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Residual stresses</value>
    </subject>
    <collection role="ddc" number="620">Ingenieurwissenschaften und zugeordnete Tätigkeiten</collection>
    <collection role="institutes" number="">9 Komponentensicherheit</collection>
    <collection role="institutes" number="">9.2 Versuchsanlagen und Prüftechnik</collection>
    <collection role="institutes" number="">9.4 Integrität von Schweißverbindungen</collection>
    <collection role="themenfelder" number="">Energie</collection>
    <collection role="themenfelder" number="">Material</collection>
    <collection role="themenfelder" number="">Degradationsmechanismen</collection>
    <collection role="fulltextaccess" number="">Datei im Netzwerk der BAM verfügbar ("Closed Access")</collection>
    <collection role="literaturgattung" number="">Präsentation</collection>
  </doc>
  <doc>
    <id>56712</id>
    <completedYear/>
    <publishedYear>2022</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>lecture</type>
    <publisherName/>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Influence of the WAAM process on residual stresses in high-strength steels (IIW-Doc. II-A-408-2022)</title>
    <abstract language="eng">High-strength fine-grain structeural steels have great potential for weight optimization of many modern engineering structures. Efficient manufacturing can be achieved here above all by Wire Arc Additive Manufacturing (WAAM). First commercial high-strength welding consumables for WAAM are already available. However, due to a lack of knowledge and guidelines for the industry regarding welding residual stresses and component safety in manufacturing and operation, their application is still severely limited. Residual stresses play a crucial role here, as the sensitive microstructure of high-strength steels carries a high risk of cold cracking. For this reason, process- and material-related influences, as well as the design aspects on residual stress formation and the risk of cold cracking, are being investigated in a recent project (FOSTA-P1380/IGF21162BG). This high strength of the WAAM welding consumables is adjusted via a martensitic phase transformation. The volume expansion associated with martensite formation has a significant influence on residual stress evolution. However, this has not yet been investigated in relation to the processing of high-strength steels by WAAM. The aim of this work is to establish a WAAM cold crack test and easy-to-apply processing recommendations that will allow economical, expedient, and crack-resistant fabrication of high-strength steels, especially for SME. This paper focuses on the analysis of the effects of welding heat control and design of WAAM components on cooling conditions, microstructure, mechanical-technological properties and residual stresses. For this purpose, geometrically defined specimens (hollow cuboids) are welded fully automatically with a special, high-strength WAAM solid wire (yield strength &gt;790 MPa). The heat control and specimen dimensions are varied within a statistical experimental design. The weld heat control is adjusted in such a way that the t8/5 cooling times are ensured within the recommended processing range (approx. 5–20 s). For this purpose, additional thermo-physical forming simulations using a dilatometer allowed the complex heat cycles to be reproduced and the resulting ultimate tensile strength of the weld metal to be determined. The WAAM welding of complex geometries with varying welding heat control and geometric factors or wall thicknesses not only has an effect on the cooling conditions, cooling times and microstructure, but also has a significant influence on the structural restraint conditions during welding. Hence, the welding experiments show significant effects of specimen scaling and heat input on the welding residual stresses, which may be detrimental regarding component properties and crack-critical tensile residual stresses. These complex interactions are analyzed within this investigation.</abstract>
    <enrichment key="eventName">Intermediate Meeting of IIW Comissions II and IX</enrichment>
    <enrichment key="eventPlace">Online meeting</enrichment>
    <enrichment key="eventStart">17.03.2022</enrichment>
    <enrichment key="opus.source">publish</enrichment>
    <enrichment key="opus.doi.autoCreate">false</enrichment>
    <enrichment key="opus.urn.autoCreate">true</enrichment>
    <enrichment key="InvitedTalks">0</enrichment>
    <author>Karsten Wandtke</author>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>MAG-Welding</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Additive Manufacturing</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Residual stresses</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>high-strength steel</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>cold cracking safety</value>
    </subject>
    <collection role="ddc" number="620">Ingenieurwissenschaften und zugeordnete Tätigkeiten</collection>
    <collection role="institutes" number="">9 Komponentensicherheit</collection>
    <collection role="institutes" number="">9.2 Versuchsanlagen und Prüftechnik</collection>
    <collection role="institutes" number="">9.4 Integrität von Schweißverbindungen</collection>
    <collection role="themenfelder" number="">Energie</collection>
    <collection role="themenfelder" number="">Material</collection>
    <collection role="themenfelder" number="">Degradationsmechanismen</collection>
    <collection role="fulltextaccess" number="">Datei im Netzwerk der BAM verfügbar ("Closed Access")</collection>
    <collection role="literaturgattung" number="">Präsentation</collection>
    <collection role="themenfelder" number="">Additive Fertigung</collection>
  </doc>
  <doc>
    <id>56671</id>
    <completedYear/>
    <publishedYear>2022</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst/>
    <pageLast/>
    <pageNumber/>
    <edition/>
    <issue/>
    <volume/>
    <type>lecture</type>
    <publisherName/>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>0</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Residual stresses in near-component specimens of a high and a medium entropy alloy due to tig and friction stir welding</title>
    <abstract language="eng">The new alloying concept of multi-element systems with defined entropy (HEA - High Entropy Alloy or MEA - Medium Entropy Alloy) is gaining increasing importance in materials research. Significantly improved properties or combinations of properties are shown by some HEA/MEA-systems, which have the potential to substitute conventional alloys such steels and are therefore promising for a wide range of applications, e.g., overcome of the trade-off between high strength and ductility. Thus, primarily the production and resulting microstructures of HEA as well as properties have been investigated so far. Furthermore, processing is a main issue to transfer HEA systems from the laboratory to real components, e.g., for highly stressed components. Since welding is the most important joining process for metals, it is crucial to investigate the influence of welding processing on these material properties to guarantee component integrity. Welding leads to residual stresses, which significantly affect the component integrity. Only a very few studies on the effect of welding on residual stresses in HEA and MEA weld joints are available so far. Hence, the focus of this study is the residual stress formation and distribution in a CoCrFeMnNi HEA and ternary CoCrNi MEA using two different welding processes: Tungsten Inert Gas (TIG) welding and soldi-state Friction Stir Welding (FSW). As a pathway for application of HEA in this investigation for the first time residual stress analyses in realistic near-component specimens were performed. The residual stresses were determined by X-ray diffraction (XRD) on the surfaces of top and root weld side. The results were correlated with the local welding microstructures. The results show that both FSW and TIG generate significant tensile residual stresses on the weld surfaces in and transverse to the welding direction. In the case of FSW of the CoCrFeMnNi HEA, the longitudinal residual stresses are in the range of the yield strength of approx. 300 MPa in the weld zone.</abstract>
    <enrichment key="eventName">OVGU-Kolloquium (BMDK des IWF)</enrichment>
    <enrichment key="eventPlace">Online meeting</enrichment>
    <enrichment key="eventStart">19.05.2022</enrichment>
    <enrichment key="opus.source">publish</enrichment>
    <enrichment key="opus.doi.autoCreate">false</enrichment>
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    <enrichment key="InvitedTalks">0</enrichment>
    <author>Tim Richter</author>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>High Entropy Alloy</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Welding</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Residual stresses</value>
    </subject>
    <subject>
      <language>eng</language>
      <type>uncontrolled</type>
      <value>Microstructure</value>
    </subject>
    <collection role="ddc" number="620">Ingenieurwissenschaften und zugeordnete Tätigkeiten</collection>
    <collection role="ddc" number="621">Angewandte Physik</collection>
    <collection role="institutes" number="">9 Komponentensicherheit</collection>
    <collection role="institutes" number="">9.2 Versuchsanlagen und Prüftechnik</collection>
    <collection role="institutes" number="">9.4 Integrität von Schweißverbindungen</collection>
    <collection role="themenfelder" number="">Energie</collection>
    <collection role="themenfelder" number="">Material</collection>
    <collection role="themenfelder" number="">Degradationsmechanismen</collection>
    <collection role="fulltextaccess" number="">Datei im Netzwerk der BAM verfügbar ("Closed Access")</collection>
    <collection role="literaturgattung" number="">Präsentation</collection>
    <collection role="institutes" number="">9.0 Abteilungsleitung und andere</collection>
  </doc>
</export-example>
