@article{NadammalCabezaMishurovaetal.2017,
  author    = {Nadammal, Naresh and Cabeza, Sandra and Mishurova, Tatiana and Thiede, Tobias and Kromm, Arne and Seyfert, Christoph and Farahbod, Lena and Haberland, Christoph and Schneider, Judith Ann and Portella, Pedro Dolabella and Bruno, Giovanni},
  title     = {Effect of hatch length on the development of microstructure, texture and residual stresses in selective laser melted superalloy Inconel 718},
  series = {Materials \& Design},
  volume    = {134},
  journal   = {Materials \& Design},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0264-1275},
  doi       = {10.1016/j.matdes.2017.08.049},
  pages     = {139 -- 150},
  year      = {2017},
  abstract  = {In the present study, samples fabricated by varying the deposition hatch length during selective laser melting of nickel based superalloy Inconel 718 were investigated. Microstructure and texture of these samples was characterized using scanning electron microscopy, combined with electron back-scattered diffraction, and residual stress assessment, using neutron diffraction method. Textured columnar grains oriented along the sample building direction were observed in the shorter hatch length processed sample. A ten-fold increase in the hatch length reduced the texture intensity by a factor of two attributed to the formation of finer grains in the longer hatch length sample. Larger gradients of transverse residual stress in the longer hatch length sample were also observed. Along the build direction, compressive stresses in the shorter hatch length and negligible stresses for the longer hatch length specimen were observed. Changes to the temperature gradient (G) in response to the hatch length variation, influenced the G to growth rate (R) ratio and the product GxR, in agreement with the microstructures and textures formed. For the residual stress development, geometry of the part also played an important role. In summary, tailored isotropy could be induced in Inconel 718 by a careful selection of parameters during selective laser melting.},
  language  = {en}
}
@article{MishurovaArtztHaubrichetal.2018,
  author    = {Mishurova, Tatiana and Artzt, Katia and Haubrich, Jan and Requena, Guillermo and Bruno, Giovanni},
  title     = {New aspects about the search for the most relevant parameters optimizing SLM materials},
  series = {Additive manufacturing},
  volume    = {25},
  journal   = {Additive manufacturing},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {2214-8604},
  doi       = {10.1016/j.addma.2018.11.023},
  pages     = {325 -- 334},
  year      = {2018},
  abstract  = {While the volumetric energy density is commonly used to qualify a process parameter set, and to quantify its influence on the microstructure and performance of additively manufactured (AM) materials and components, it has been already shown that this description is by no means exhaustive. In this work, new aspects of the optimization of the selective laser melting process are investigated for AM Ti-6Al-4V. We focus on the amount of near-surface residual stress (RS), often blamed for the failure of components, and on the porosity characteristics (amount and spatial distribution). First, using synchrotron x-ray diffraction we show that higher RS in the subsurface region is generated if a lower energy density is used. Second, we show that laser de-focusing and sample positioning inside the build chamber also play an eminent role, and we quantify this influence. In parallel, using X-ray Computed Tomography, we observe that porosity is mainly concentrated in the contour region, except in the case where the laser speed is small. The low values of porosity (less than 1\%) do not influence RS.},
  language  = {en}
}
@article{StegemannCabezaPelkneretal.2018,
  author    = {Stegemann, Robert and Cabeza, Sandra and Pelkner, Matthias and Lyamkin, Viktor and Pittner, Andreas and Werner, Daniel and Wimpory, Robert and Boin, Mirko and Kreutzbruck, Marc and Bruno, Giovanni},
  title     = {Influence of the microstructure on magnetic stray fields of low-carbon steel welds},
  series = {Journal of Nondestructive Evaluation},
  volume    = {37},
  journal   = {Journal of Nondestructive Evaluation},
  number    = {3},
  publisher = {Springer},
  address   = {New York},
  issn      = {0195-9298},
  doi       = {10.1007/s10921-018-0522-0},
  pages     = {18},
  year      = {2018},
  abstract  = {This study examines the relationship between the magnetic mesostructure with the microstructure of low carbon steel tungsten inert gas welds. Optical microscopy revealed variation in the microstructure of the parent material, in the heat affected and fusion zones, correlating with distinctive changes in the local magnetic stray fields measured with high spatial resolution giant magneto resistance sensors. In the vicinity of the heat affected zone high residual stresses were found using neutron diffraction. Notably, the gradients of von Mises stress and triaxial magnetic stray field modulus follow the same tendency transverse to the weld. In contrast, micro-X-ray fluorescence characterization indicated that local changes in element composition had no independent effect on magnetic stray fields.},
  language  = {en}
}
@article{FernandezCabezaMishurovaetal.2018,
  author    = {Fernandez, R. and Cabeza, Sandra and Mishurova, Tatiana and Fernandez-Castrillo, P. and Gonzalez-Doncel, Gaspar and Bruno, Giovanni},
  title     = {Residual stress and yield strength evolution with annealing treatments in an age-hardenable aluminum alloy matrix composite},
  series = {Materials Science and Engineering: A},
  volume    = {731},
  journal   = {Materials Science and Engineering: A},
  publisher = {Elsevier},
  address   = {Lausanne},
  issn      = {0921-5093},
  doi       = {10.1016/j.msea.2018.06.031},
  pages     = {344 -- 350},
  year      = {2018},
  abstract  = {We investigated the possibility of minimizing tensile matrix residual stresses in age hardenable aluminum alloy metal matrix composites without detrimentally affect their mechanical properties (such as yield strength). Specifically, we performed thermal treatments at different temperatures and times in an age-hardenable aluminum matrix composite 2014Al-15vol\%Al2O3. Using X-ray synchrotron radiation diffraction and mechanical tests, we show that below a certain treatment temperature (250 degrees C) it is possible to identify an appropriate thermal treatment capable of relaxing residual stress in this composite while even increasing its yield strength, with respect to the as processed conditions.},
  language  = {en}
}
@article{SevostianovBruno2018,
  author    = {Sevostianov, Igor and Bruno, Giovanni},
  title     = {Maxwell scheme for internal stresses in multiphase composites},
  series = {Mechanics of Materials},
  volume    = {129},
  journal   = {Mechanics of Materials},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0167-6636},
  doi       = {10.1016/j.mechmat.2018.12.005},
  pages     = {320 -- 331},
  year      = {2018},
  abstract  = {The paper focuses on the reformulation of classic Maxwell's (1873) homogenization method for calculation of the residual stresses in matrix composites. For this goal, we equate the far fields produced by a set of inhomogeneities subjected to known eigenstrains and by a fictitious domain with unknown eigenstrain. The effect of interaction between the inhomogeneities is reduced to the calculation of the additional field acting on an inhomogeneity due to the eigenstrains in its neighbors. An explicit formula for residual stresses is derived for the general case of a multiphase composite. The method is illustrated by several examples. The results are compared with available experimental data as well as with predictions provided by the non-interaction approximation (Eshelby solution). It is shown that accounting for interaction can explain many experimentally observed phenomena and is required for adequate quantitative analytical modeling of the residual stresses in matrix composites.},
  language  = {en}
}