TY - GEN A1 - Cross, Carl Edward A1 - Coniglio, Nicolas A1 - Schempp, Philipp A1 - Mousavi, M.G. ED - Lippold, J. ED - Böllinghaus, Thomas ED - Cross, C.E. ED - et al., T1 - Critical conditions for weld solidification crack growth N2 - The occurrence of solidification cracking during welding remains a little understood phenomenon, in spite of extensive studies and tests performed to evaluate and compare the relative weldability of many different alloys. From an approach often adopted in the welding community attributed to Prokhorov, solidification cracks are believed to form when a critical tensile strain is exceeded, specific to the alloy, assuming that the mushy-zone has limited ductility. Tensile stresses and strains normally form behind a moving weld pool as a result of solidification shrinkage and thermal contraction, as influenced by welding parameters and the degree of restraint. KW - Solidification cracking KW - Aluminium alloy KW - Crack growth KW - Strain rate model PY - 2011 SN - 978-3-642-16863-5 DO - https://doi.org/10.1007/978-3-642-16864-2_2 IS - Part 2 SP - 25 EP - 41 PB - Springer CY - Berlin, Heidelberg AN - OPUS4-23846 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ben-Hamu, G. A1 - Eliezer, D. A1 - Cross, Carl Edward A1 - Böllinghaus, Thomas T1 - Volta potential of second phase particles in TIG welded AZ31 magnesium sheet T2 - EUROCORR 2006 CY - Maastricht, The Netherlands DA - 2006-09-25 KW - TIG welding KW - AZ31 Magnesium Alloy KW - Corrosion behavior PY - 2006 N1 - Serientitel: EFC-Event – Series title: EFC-Event IS - 280 SP - 1 EP - 10 PB - European Federation of Corrosion CY - Maastricht AN - OPUS4-22134 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Eliezer, Dan A1 - Tal-Gutelmacher, E. A1 - Cross, Carl Edward A1 - Böllinghaus, Thomas T1 - Hydrogen absorption and desorption in a duplex-annealed Ti-6Al-4V alloy during exposure to different hydrogen-containing environments N2 - Based on its excellent combination of a high strength/weight ratio and good corrosion behavior, Ti–6Al–4V alloy is ranked among the most important advanced materials for a variety of industrial applications. However, in many of these technological applications, this alloy is exposed to environments which can act as sources of hydrogen, and severe problems may arise based on its susceptibility to hydrogen embrittlement. Even small hydrogen concentrations might lead to failure. Consequently, a comprehensive knowledge of hydrogen's absorption/desorption behavior and interactions between hydrogen and different microstructural features is necessary to better understand the desorption and trapping mechanisms, the types of the trap sites, and the trapped hydrogen content, in order to determine the safe service conditions of this alloy in the industry. In this paper, different characteristics of hydrogen's absorption/desorption behavior and trapping in a duplex-annealed Ti–6Al–4V alloy are studied by means of thermal desorption spectroscopy (TDS). Spectra analysis is supported by data from a variety of other experimental techniques, such as LECO hydrogen determinator, XRD and microstructure investigations by means of optical and electron microscopy. Hydrogen evolution is found to be a very complex process, being affected by the way hydrogen was initially introduced to the alloy, the phase transformations that may occur during the thermal analysis and the presence of potential trapping sites. KW - Titanium alloys KW - Hydrogen absorption KW - Hydrogen desorption KW - Ti-6Al-4V KW - Thermal desorption spectroscopy (TDS) PY - 2006 DO - https://doi.org/10.1016/j.msea.2006.06.088 SN - 0921-5093 SN - 1873-4936 VL - 433 IS - 1-2 SP - 298 EP - 304 PB - Elsevier CY - Amsterdam AN - OPUS4-14484 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Cross, Carl Edward A1 - Coniglio, Nicolas ED - Carl E. Cross, ED - John C. Lippold, ED - Böllinghaus, Thomas ED - Herold, H. T1 - Weld solidification cracking: critical conditions for crack initiation and growth N2 - A perspective will be given that outlines important considerations in evaluating and predicting weldability. An examination will be made of the local conditions necessary for solidifications crack initiation and growth in a weld. This will be done in light of two prominent thermo-mechanical approaches involving critical strain and critical strain rate. Critical conditions will be identified based upon values available in the literature. Methods used to measure strain and strain rate will be compared. The interpretation of crack lenght measurements commonly used to quantify weldability will be questioned, based upon our current understanding of the problem. Complications and problem areas needing better definition will be identified and discussed, including strain distribution in the mushy zone, segregation at grain boundaries, effect of impurities, and effect of cooling rate on solidification path. Finally, a suggestion will be made for a new approach to weld development using in-situ strain rate measurements and new composition-strain rate maps that define the boundary between crack an no-crack conditions. T2 - Hot cracking phenomena in welds II CY - Berlin, Germany DA - 2007-03-05 KW - Solidification Cracking KW - Hot Cracking KW - Crack Initiation KW - Crack Growth KW - Critical Strain KW - Critical Strain Rate KW - Weldability Testing KW - Crack Prediction PY - 2008 SN - 978-3-540-78627-6 SP - 39 EP - 58 PB - Springer CY - Berlin AN - OPUS4-18319 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Coniglio, Nicolas A1 - Cross, Carl Edward ED - Carl E. Cross, ED - John C. Lippold, ED - Böllinghaus, Thomas ED - Herold, H. T1 - Weld parameter and minor element effects on solidification crack initiation in Aluminium N2 - Earlier work has established that a critical amount of 4043 filler is required to avoid solidification cracking when arc-welding 6060 aluminium, depending upon local strain conditions. For example, when the mushy zone behind the weld pool experiences a tensile strain from combined thermal and shrinkage stresses, the possibility exists for crack initiation. For a greater rate of strain, it has been determined that a greater 4043 dilution (i.e. higher weld metal silicon content) is required to avoid crack initiation. Making use of the Controlled Tensile Weldability (CTW) test and local strain extensometer measurements, a boundary has been established between crack and no-crack conditions for different local strain rates and filler dilutions, holding all other welding parameters constant. Using this established boundary as a line of reference, additional parameters have now been examined and their influence on cracking has been characterized. These parameter influences have included studies of weld travel speed, weld pool contaminants (Fe, O, and H), and grain refiner additions (TiAl3 + Boron). Each parameter has been independently varied and its effect on cracking susceptibility quantified in terms of a critical strain rate required to initiate cracking for a given 4043 filler dilution. T2 - Hot cracking phenomena in welds II CY - Berlin, Germany DA - 2006-03-05 KW - Aluminium Alloys KW - Solidification Cracking KW - Weld Defect KW - Hot Cracking KW - Crack Initiation KW - Critical Strain Rate KW - Parameter Effects KW - Minor Elements PY - 2008 SN - 978-3-540-78627-6 SP - 277 EP - 310 PB - Springer CY - Berlin AN - OPUS4-18323 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eliezer, Dan A1 - Tal-Gutelmacher, E. A1 - Cross, Carl Edward A1 - Böllinghaus, Thomas ED - Gdoutos, E. T1 - Irreversible Hydrogen Trapping in Welded Beta-21S Titanium Alloy T2 - 16th European Conference of Fracture CY - Alexandroupoli, Greece DA - 2006-07-03 KW - Titanium alloys KW - Beta-21S KW - Hydrogen desorption KW - Thermal Desorption Spectroscopy (TDS) PY - 2006 VL - 16 IS - 803 SP - 1 EP - 8 CY - Alexandroupolis AN - OPUS4-14453 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kannengießer, Thomas A1 - Cross, Carl Edward A1 - Böllinghaus, Thomas ED - Karl-Heinrich Grote, ED - Erik K. Antonsson, T1 - Modern Joining Technology - Weld Simulation PY - 2009 SN - 978-3-540-49131-6 IS - Part B / 7.4.8 SP - 706 EP - 723 PB - Springer AN - OPUS4-19047 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -