P. A. Prasob ¹, M. Sasikumar ¹, P. Tamil Selvan ¹

Affiliations
1 School of Mechanical and Building Science (SMBS), VIT University, Chennai Campus, Tamil Nadu, IN

Abstract

Background/Objective: The objective of this review paper is to know and verify the mechanical properties especially impact behavior of PMC under subzero temperature. Methods/Statistical Analysis: The focus of this paper is on the use of liquid nitrogen as cryogenic liquid, subzero temperature conditions and the mechanical durability of PMC including tensile strength, compressive strength, shear strength, fatigue. The low velocity impact of PMC is reviewed under the Charpy impact and the Drop weight impact. Also the progressive failure and damage of PMC under impact is given due importance in this paper. Applications/Improvements: Hybridization of PMC with synthetic, natural fibers and micro fillers can enhance the mechanical properties of PMC at liquid nitrogen temperature. Findings: The tensile load response for a composite is very much dependent on the strength properties of the reinforcement fibers, since they are high compared to the resin system on its own. The compression testing of the composites is very challenging due to various reasons. The application of compressive load on the cross section is done in three ways: directly apply the compressive load on the ends of a specimen, loading the edges in shear and mixed shear and direct loading. The compression test results show that the mechanical properties at subzero temperature is comparatively better than properties of the PMC at room temperature. The impact testing of PMC in subzero temperature has better impact strength than PMC tested at room temperature. The reason being the brittleness of the matrix once exposed to liquid nitrogen the layers get contracted on cooling and load transfer does not take place as in the case of composite at room temperature resulting in failure.

Keywords

Cryogenics, Damage, Impact, Polymer Matrix Composite (PMC), Liquid Nitrogen, Subzero.

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P. A. Prasob ¹, M. Sasikumar ¹, Navneet Bardiya ¹, P. Vasundhra ²

Affiliations
1 School of Mechanical and Building Sciences (SMBS), VIT University, Chennai Campus, Chennai - 600127, Tamil Nadu, IN
2 CVRDE, Defense Research and Development Organization, Avadi, Chennai - 600 054, Tamil Nadu, IN

Abstract

Objectives: The objective of this paper is to study the influence of interface between multi layered composite structures in penetration problems, using finite element solver RADIOSS. Methods/Statistical Analysis: Finite element modeling of the penetrating projectile, multilayer composite and analysis using RADIOSS is done. The analysis is confined to Johnson Cook material model for plasticity and failure. One of the important aspects of material model is the representation of the plasticity and failure region. The modified interface creates a realistic environment with combination of TYPE 2 and TYPE 7 influences multiple hit of projectiles and does not influence the depth of penetration when compared to the TYPE 7 interface. Findings: Hyper Works software tool is used to simulate the projectile penetrating armor plate and Hyper Mesh used for preprocessing and RADIOSS as a solver. The depth of penetration is not significantly affected due to the TYPE 2 interface. However, the delamination behavior of the layers is captured in the TYPE 2 interface when compared to TYPE7. The modified interface with combination of TYPE 2 and TYPE 7 does not influence the depth of penetration when compared to the TYPE 7 interface. TYPE 7 formulations gives considerably acceptable results for capturing the depth of penetration in case of multilayer composite structures. TYPE 2 interfaces has to be studied in cases where delamination has influence, for example in multiple hits of projectiles etc. Application/Improvements: Development of alternative material or sandwich structure is required for the future war scenario to prevent the main threats for Armored Fighting Vehicles (AFVs), shock and penetration as future war scenario insists on light tanks that can withstand penetration with higher order of destruction.

Keywords

Armoured Fighting Vehicle (AFV), Finite Element Modeling, 7.62 mm Projectile, Multi Material.

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