P. Rama Subba Reddy; T. Sreekantha Reddy; I. Srikanth; P. Ghosal; V. Madhu; K. Venkateswara Rao
Abstract
S2-glass/epoxy composite laminates were made by varying the nanoclay content from 0-12% by weight and were subjected to low velocity impact at 50 J, 110 J and 150 J incident energy respectively. It is observed that at 50 J impact energy, which is below penetration limit of laminate the presence of nanoclay ...
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S2-glass/epoxy composite laminates were made by varying the nanoclay content from 0-12% by weight and were subjected to low velocity impact at 50 J, 110 J and 150 J incident energy respectively. It is observed that at 50 J impact energy, which is below penetration limit of laminate the presence of nanoclay could not add any advantage in total energy absorption. As the impact energy increased to 110 J (near penetration limit), nano composite laminates have shown 37% improvement in energy absorption compared to pristine laminate. Composite with 9% nanoclay has shown optimum performance in terms of energy absorption, penetration limit velocity and decrease in maximum displacement. Further increase of impact energy upto 150 J (above penetration limit) has not resulted in any improvement in energy absorption. Post impact analysis reveals that the total damage area of laminates increased with increase in impact energy and nanoclay content. Fractured area of impacted laminates calculated and observed that the fractured area of laminate decreased with increase of nanoclay content. Present study highlights that besides optimum nanoclay content, optimum impact conditions also play a vital role in deriving benefits of nanocomposites.
T. Sreekantha Reddy; P. Rama Subba Reddy; V. Madhu
Abstract
Hybrid composites find applications in many advanced fields that include aerospace and armour due to their high specific strength and high energy absorption capacity. The present study has attempted to develop cost effective E and S2 glass based hybrid composites for armour applications in order to get ...
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Hybrid composites find applications in many advanced fields that include aerospace and armour due to their high specific strength and high energy absorption capacity. The present study has attempted to develop cost effective E and S2 glass based hybrid composites for armour applications in order to get advantages of both fibres i.e superior impact properties at reduced cost. Three hybrid composites based on E glass and S2 glass in the volume ratios of 75:25, 50:50 and 25:75 were fabricated using epoxy matrix. Low velocity impact (60-110 J energy) experiments using instrumented drop tower on 2 mm thickness laminates show that composites perform better when impacted on E glass strike face than on S2 glass strike face. Hybrid composite made of 25% E glass and 75 % S2 glass (ES 25-75) has shown equal performance to that of 100 % S2 glass/epoxy (S 100) laminate. Ballistic evaluation on 6 mm thick laminates against 7.62 mm mild steel projectile also prove that the performance of hybrid composites increases with increase in S2 glass content and ES 25-75 composite performs similar to S 100 laminate in terms of energy absorption as well as damage volume.
Dipen Kumar Rajak; L. A. Kumaraswamidhas; S. Das
Abstract
Aluminium foam is an isotropic porous metal of cellular structure in the order of 75-80 vol. % of the pores. In turn the novel mechanical, physical and chemical composition, properties depends on the density of foam, i.e. lies in between 0.4-2.4 g/cm 3 . Aluminium foam filled structures are used in collide, ...
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Aluminium foam is an isotropic porous metal of cellular structure in the order of 75-80 vol. % of the pores. In turn the novel mechanical, physical and chemical composition, properties depends on the density of foam, i.e. lies in between 0.4-2.4 g/cm 3 . Aluminium foam filled structures are used in collide, energy absorption, sound absorbing and vibration damping applications. In this article the compressive deformation behaviour of rectangular, square and round aluminium foam (LM 25 + 10wt% SiCp) filled and empty mild steel samples respectively are analyzed to identify the more energy absorption rate per unit volume in diverse strain rate by means of the compressive testing at room temperature. The experiments were performed on a universal testing machine the results showed that the round cross-section had more energy absorption than the rectangular and square cross section respectively. Also the amount of energy absorption will be greater with low foam density for round section tubes. We have seen that an increasing interest in using aluminium foams as inside the thin-wall mild steel tubes for maximum specific energy absorption rate. This work shows the admirable capability of aluminium alloy foam in applications in which it is essential to absorb compression energy.