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In this research, forming limit diagram (FLD) of aluminum alloy 1050 (AA 1050) sheet produced by Accumulative Roll Bonding (ARB) is investigated numerically and experimentally. The Gurson-Tvergaard-Needleman (GTN) ductile damage model is used to predict sheet failure and obtain its FLD using numerical simulation in Abaqus/Explicit. Nucleation and growth of voids in the material during the deformation is the basic concept of the GTN damage model. This damage model has nine basic parameters that obtaining through experimental tests is time-consuming and costly, and in some cases, impossible. Thus, the present study tries to obtain the above parameters for fine-grained aluminum 1050 fabricated by ARB using the finite element method. Therefore, after considering each parameter's interval, numerical simulation and the anti-inference method are used in the uniaxial tensile test to identify GTN parameters for the AA 1050 sheet using FEM. The optimum parameters of the GTN model are used in the FEM of the Nakazima test for FLD prediction. Also, The FLD of the fine-grained aluminum sheet is obtained experimentally using the Nakazima test. Finally, the numerical and experimental FLDs are compared for validation. [ABSTRACT FROM AUTHOR]

This paper presents a biaxial fretting fatigue test bench which provides the capability of performing fretting fatigue experiments on individual wires of a conductor combining the effect of both alternating tension and bending loadings to represent a more realistic state of a conductor individual strand under periodic loading caused by aeolian vibrations. Preliminary tests with only uniaxial alternating tension loading were carried out on 1350-H19 aluminum wires having the same mechanical and geometric characteristics as those of the ACSR Bersfort conductor aluminum strands. Different levels of alternating stress were tested in order to validate the performance of the apparatus. Preliminary results showed that the experimental setup allows reproducing the local loading state which leads to the fretting fatigue damage on the tested wires. Biaxial tests were also conducted at a high level of alternating loadings. The results of these tests reveals that, at high alternating stress amplitudes, the biaxial loading allows to observe some fretting fatigue failures, whereas early plain fatigue failures were observed when applying similar uniaxial loading.

Rail transport, specifically diesel–electric trains, faces fundamental challenges in reducing fuel consumption to improve financial performance and reduce GHG emissions. One solution to improve energy efficiency is the electric brake regenerative technique. This technique was first applied on electric trains several years ago, but it is still considered to improve diesel–electric trains efficiency. Numerous parameters influence the detailed estimation of brake regenerative technique performance, which makes this process particularly difficult. This paper proposes a simplified energetic approach for a diesel–electric train with different storage systems to assess these performances. The feasibility and profitability of using a brake regenerative system depend on the quantity of energy that can be recuperated and stored during the train's full and partial stop. Based on a simplified energetic calculation and cost estimation, we present a comprehensive and realistic calculation to evaluate ROI, net annual revenues, and GHG emission reduction. The feasibility of the solution is studied for different train journeys, and the most significant parameters affecting the impact of using this technique are identified. In addition, we study the influence of electric storage devices and low temperatures. The proposed method is validated using experimental results available in the literature showing that this technique resulted in annual energy savings of 3400 MWh for 34 trains, worth USD 425,000 in fuel savings. [ABSTRACT FROM AUTHOR]