Effect of orientation of glass fiber mat in epoxy matrix on mechanical properties

Abstract

IIigh p~r1(mnancc composites are currently being used In the marine, automotive, aerospace and defense industries. These industries demand materials with propeni~s that arc similar or better than conventional metals at a fr,,<:tion or the weight. The design of composite structures is challenging du~ to the complex mechanical behavior of the structures and the number of design variables involved. A composite laminale is typically formed from a number of fibcr-reinforced luyers having dir~ctional properties. l3asically, lor each layer of the laminate, the design variables are the choice of mal erial system, thickness und orienlalion of the layers. '1he objective 0[' Ihis research work ""USto ~valuate the effects of glass fiber mats (CSM and R,V1)orientation and the dimensions (3D) of orientation on the mechanical propertie~ in compare with ~poxy matrix and other types 01"ori~n!.ations by testing under tcnsile loading syslem. A die was designed prior 10manufacture the composite samples and the samples were prepared a~ per ASTM standards. An Instron machine was used for tensile loading test. All specimens were tested to faill1l'e in order to characterize the elJ",cl of maximum strain on failure <;trcngthof the material. The fib~r volume fraction~ (FVFs) of all types of composite specimen were mea~ufed in a conventional method. Experimental values were obtained for len~ilc modulus, maximum Sire", and the str"in at maximum stress in all three directions. It was ~xperimentally found that Composite of 3D urientation of CSM provid~d 81.46% higher strength, whereas other horizontal orientations ofCSM with and without woven roving mat provided 43.73%, 52.53% and 56.2% higher slrength over epoxy matrix. The 3D oriented GFR cOlllp(l~itealso absorbed 114.15% and 153.05% higher energy than epoxy matrix both to initiate crack ilnd to fracture respectively. 'Whereas other types or horizontally oriented GFR composites absorbed 85.69%, 76.0%, 35.23% and 93.37%, 91.1\4%, 39.11% higher energy than epoxy matrix both to initiate crack lmd to fracture respectively. The 3D oriented GFR composite was, therefore, more toughened than other types of composites.