Effect of Supersonic Shock Wave Loading on Thin Metallic Sheets: Experimental and Numerical Studies

Defence structures are under high threat of blast loading in recent years due to rising terrorist activities. Protection of defence structures against blast conditions has received a huge interest in the past few years. Blast mitigation requires to study the behavior of various metals under supersonic shock loading. An experimental study was carried out using in-house developed shock tube apparatus to understand effect of shock loading on mild steel and aluminum sheets. A limitation of current study is 1-D loading occurring in shock tube which is unlike 3-D loading occurring in a blast event. Experiments reveal that the properties of thin sheets in through-thickness direction plays an essential role in the shock transfer, which affects considerably the failure and final deformed shape of the sheet. The study showed that metallic thin sheets absorbed shock energy via plastic deformation and failed via a tensile failure mode. Results from this study indicate that aluminum sheets and mild steel sheets can offer shock-resistant properties and mitigate more energy via absorption and plastic deformation. Aluminum and mild steel sheets can therefore be used as a face and back sheet for the development of any sandwich composites.