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Abstract Presence of impurities in a mechanical system have a great effect on its mechanical properties, some impurities can defeat fatigue life, while others may exert a highly careful effect. The principal usage of Aluminum alloys is in the production of plane light structures, panels, and metallic frameworks. The second largest consumer is the industrial vessels; this shows clearly the fastest growth with aluminum alloys as an alternative solution instead of steel and cast iron in industry. Two aluminum alloys were used to study effect of adding alloying element such as Silicon (Si) on mechanical dynamical properties (fatigue life) of these two selected alloys, they are Al-5Si (4043) and Al-12Si (4047). Fatigue tests are carried out on these specimens under rotating bending conditions to get the S-N curves. The S-N curves show fracture at around over 108 cycles without certain endurance limit for both alloys where the two employed specimens are aluminum based alloys, hence, each one will not exhibit a specific value of endurance limit. The final results showed that, for the first alloy, cracks initiate in the medium of aluminum and then rapid progress towards the alloying element (Si), so this means crack initiation is the governing factor for fatigue life for this aluminum alloy. For the second alloy, cracks start from alloying element (Si) at first and then directed towered the aluminum matrix, also. Al-12Si (4047) shows best largely fatigue resistance than the other alloy, sure this depends on the so small volume occupied by alloying element comparing with aluminum matrix. © 2020, Springer Nature B.V.

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Abstract Purpose: The purpose of this paper is to investigate the effect of graphene platelets (GPLs) on the low-speed contact between a mass and surface of a multi-layer polymer beam. Design/methodology/approach: This problem is primarily organized by first-order shear deformation beam theory and nonlinear Hertz rule. GPLs are distributed along the beam thickness direction. The Halpin–Tsai micromechanics model is applied for computing the effective Young’s modulus of the GPLs/polymer composites. In the formulation process, the principle of conservation of energy is first used and the histories of results are extracted using the separation of variables and Runge–Kutta method. Findings: In comparing the responses with the available data, a good agreement is observed. The effects of the weight fraction and distribution pattern on the impact response of polymer beam reinforced with GPLs are studied. Results show that contact force is increased, contact time and beam recess are decreased with increasing of weight fraction of GPLs. Also, among the different distribution patterns, the contact force depended on value of GPLs at the point of contact. Originality/value: The effects of GPLs addition on the multi-layer polymer beam has a novelty in impact problems. © 2021, Emerald Publishing Limited.

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When performing the actual additional sheet forming procedures, it is expected to be exposed to Tool failure and physical failure. So, the risks should be within their minimums. This research aims to predict material failure as well as tools. The quantitative and hypothetical method was adopted as a controller of the solid formation and weight parts formation. Overlay sheet metal forming strategies define boundaries. The use of progressive sheet materials makes new hard tasks simulate procedures due to the formability of materials strengthens associated with classical steel metal. The following may cause a fractured challenges situation may occur information action, also It has been faced nonharmony case in materials forming possessions supplied by the deferent vendors. Moreover, the other challenge is represented through high interacted stress with high heat throughout formatting processing, which leads to a reduction in the tool's life. The maximum forming ability and the large tendency of formed elastic material to revert before forming leads to inaccuracy of the dimensions in the part that has been formed before. © 2021 Zibeline International Publishing Sdn. Bhd.. All rights reserved.