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SiCp/Al-Fe-V-Si composites exhibit complex deformation behaviors at both room and high temperatures because of the presence of SiC reinforcement particles and numerous fine dispersed Al12(Fe, V)3Si heat-resistant phases. In this work, an artificial neural network (ANN) constitutive model was established to study the deformation behavior of SiCp/Al-7.75Fe-1.04V-1.95Si composites over a wide temperature range based on uniaxial compression. Then, microstructural observation, finite element analysis, and processing maps were utilized to investigate the plastic workability. The results showed that the ANN model fit the experimental stress–strain curves with high accuracy, achieving an R2 value of 0.999. The ANN model was embedded into finite element software to study plastic deformation behaviors, which indicated that this model could accurately compute the plastic and mechanical response during the compressing process. Finally, a thermomechanical processing diagram was developed, revealing that the optimal processing parameters of the SiCp/Al-7.75Fe-1.04V-1.95Si composites were a deformation temperature of 450–500 °C and a deformation rate of 0.1–0.2 s−1. [ABSTRACT FROM AUTHOR]

The layout of facilities in a logistics scenario involves not only the working facilities responsible for processing materials but also the transport lines responsible for transporting materials. The traditional facility layout methods do not take into account the transportation facilities nor calculate the material handling cost by Manhattan distance, thus failing to fulfill the actual requirements of industrial logistics scenarios. In this paper, a facility layout algorithm framework MOSA-FD driven by transport lines is proposed. A multi-objective simulated annealing (MOSA) algorithm is designed for both material handling cost (MHC) and transport facility cost (TFC) objectives. Then, a force-directed (FD) algorithm is applied to correct the unreasonable solutions according to the material transport lines in the logistics workshop, and a better solution is quickly obtained. Finally, by comparing the results with those of other metaheuristic multi-objective algorithms, the acceleration of the force-directed algorithm in this layout problem is demonstrated in experimental instances of different scales, and our method, compared to the MOSA algorithm, can reach optimal ratios of 36% and 80%, respectively, on the multi-objective. [ABSTRACT FROM AUTHOR]

Post annealing treatment is generally needed for additively manufactured titanium alloy to decompose metastable phases, alleviate residual stress, and improve ductility. In this work, in-situ electrical resistivity and line profile analysis of X-ray diffraction were utilized for monitoring phase transformation behaviors and dislocation evolutions of a laser powder bed fusion-built Ti-6Al-4V alloy under post annealing treatment. Besides, hardness and tensile tests were adopted for revealing the effects of phase transformation and dislocation evolutions on the mechanical properties. The results indicated that post annealing treatment decomposed martensitic α′ into lamellar α + β and eliminated dislocations efficiently. The martensite decomposition rate increased with the annealing temperature. Annealing at 700 °C for 4 h eliminated 98% of the dislocations, and further annealing has only a limited influence on the dislocation density. Annealing at 700 °C for 16 h is beneficial for achieving a high ductility of 10.3% owing to the favorable equilibrium lamellar α + β microstructure. These findings provide valuable insights for optimizing post annealing treatment procedures to enhance the mechanical properties of additively manufactured Ti-6Al-4V alloys. [ABSTRACT FROM AUTHOR]

Despite the industrial significance of grain size for enhancing mechanical properties and formability, the in-depth deformation mechanisms at elevated temperature are still unclear. To investigate the functions of grain size on hot workability and deformation mechanisms, three groups of Mg-1.2Zn-0.2Y alloy specimens with different grain sizes were hot compressed and then studied by combining constitutive model, processing map and microstructural observations. The results showed that the enhanced hot workability accompanying low deformation activation energy and small instability regime was obtained with refined grain size. During hot deformation, the decreased grain size in Mg-1.2Zn-0.2Y alloy mainly improved the plastic deformation homogeneity, especially for the weakened local straining around grain boundaries. As a result, the dynamic recrystallization nucleation and texture development at lower strain level were influenced by the initial grain size. At higher strain magnitude, the growth and coarsening of dynamic recrystallized grains would further release strain localization and improve hot workability, while the texture was less impacted. Further, unlike the primary basal slip and deformation twinning in the specimen with coarse grain at low temperature, non-basal slips of dislocations were initiated with less deformation twins in the specimens with refined grain size. [ABSTRACT FROM AUTHOR]