Effect of back pressure on impact and compression-after-impact characteristics of composites

• Published in: Composite structures Vol. 93; no. 2; pp. 944 - 951
• Main Authors: Kulkarni, Mandar D., Goel, Rahul, Naik, N.K.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 2011; Elsevier
• Subjects: Applied sciences; Atmospheric pressure; Back pressure; Barometric pressure; Composite; Composite structures; Composites; Compression-after-impact; Contact force; Curvature; Deflection; Exact sciences and technology; Forms of application and semi-finished materials; Fracture mechanics (crack, fatigue, damage...); Fundamental areas of phenomenology (including applications); Glass fiber reinforced plastics; Low velocity impact; Mathematical analysis; Mechanical contact (friction...); Physics; Plates (structural members); Polymer industry, paints, wood; Solid mechanics; Structural and continuum mechanics; Technology of polymers; Vibration, mechanical wave, dynamic stability (aeroelasticity, vibration control...); Back pressure; Composite; Compression-after-impact; Low velocity impact; Lateral load; Low speed; Central force; Epoxy resin; Traffic accident; Mechanical contact; Experimental study; Composite material; Plate; Pressure effect; Contact stress; Woven material; Glass fiber; Curvature; Mechanical shock
• ISSN: 0263-8223; 1879-1085
• DOI: 10.1016/j.compstruct.2010.06.027

Low velocity impact and compression-after-impact characteristics of a typical plain weave E-glass/epoxy composite are studied experimentally. Atmospheric pressure was maintained on the top surface and different pressures were applied on the rear side during impact experiments. Pressure on the rear side of the impacted plate is referred to as back pressure in further discussion. Effect of back pressure on the impact behavior is studied. It is observed that the variation in peak contact force and maximum central deflection are governed by two opposing phenomena. The parameters influencing the opposing phenomena are: induced curvature because of back pressure, effective pre-stressing and effective thickness. The incident impact energy was the same in all the experiments. Post-impact compressive strength was also investigated.