Comparison of quasi static indentation and dynamic loads of glass and carbon fibre aluminium laminates

Abstract

Purpose -The purpose of this paper was to compare the response of selected hybrid Fibre Metal Laminates (FMLs) in the form of glass and carbon fibre aluminium laminates to dynamic and static loads compared together. Design/methodology/approach -The subject of examination was FMLs (Al/CFRP and Al/GFRP). The samples were subjected to low-velocity impact and quasi-static indentation. The response of laminates to the both types of loads was evaluated by comparison of force -displacement diagrams including the values of maximum forces as well as the extent and nature of structure degradation as a result of loads. Findings -In case of Al/GFRP laminates, the analysis of characteristic relations, i.e. force -displacement and the impactor influence area in case of indentation and impact confirmed that certain parameters, i.e. the values of maximum force transferred by laminate, destruction surface area and destruction mechanisms are consistent after static and dynamic tests. Significant differences were found in destruction scale in Al/GFRP laminates despite considerable fitting of force -displacement diagrams to static and dynamic tests. Destruction surface area observed in FML carbon laminates subjected to dynamic loads was significantly smaller than after indentation but perforation area occurring at the unloaded side was much more extensive. Practical implications -Research issues in the scope of dynamic loads by means of concentrated force in composite materials and interpretation of the effects of their impacts are extremely complex. Therefore, the attempts are made to predict the resistance to dynamic loads by means of concentrated force using statistical research methods. The test results might be useful for the design and simulations of FMLs applications in aerospace. Originality/value -From the analysis of available literature, it appears that there are no studies exploring the issue of forecasting or comparison the effects of static and dynamic tests for hybrid FMLs. The new hybrid materials like FMLs have different mechanisms of damage initiation and propagation as a result of impact, in comparison to classic composite materials. It means that possibilities of using the static loads to predict impact resistance should be known well for all type of FMLs. Actually, there is no research about static indentation in relation to low-velocity impact of aluminium-carbon laminates. This situation encouraged the authors of the present study to undertake research in this scope. The results can demonstrate and explain why prediction of impact resistance of FMLs by using static indentation is uncertain and not always valuable.

The influence of fibre orientation in aluminium–carbon laminates on low-velocity impact resistance

“…6,10,25,27 The course of f–t curves as well as the value of P i and P m may constitute a basis for assessment and comparison of the composite material and FMLs resistance to low-velocity impact. 8,12,24,28–31…”

Experimental investigation on mechanical behavior of fiber–metal laminates reinforced by hybrid carbon nanotubes and nanosilica under quasi-static pressure load

“…They analyzed the effect of various mechanical and chemical surface preparation methods (including alkaline process and engraving with sulfochochromic solution) on bending behavior using a three-point bending test. Jakubczak and Bienias 35 considered the quasi-static indentation of glass fiber-reinforced aluminum FML plates against static and dynamic loads. The results of their study presented that the level of degradation observed in carbon FMLs exposed to dynamic loads is significantly smaller than the indentations created against quasi-static loads.…”

Buckling of fiber metal laminated plates – numerical and experimental studies

“…The low-velocity impact behavior of FMLs was examined by Jakubczak et al (2014). Jakubczak and Bienias (2016) reported the experimental results on FMLs subjected to low-velocity impact and quasi-static loading. Most of the studies mentioned above are focused on the impact behavior of FMLs.…”