In situ damage sensing in the glass fabric reinforced epoxy composites containing CNT–Al2O3 hybrids

Detection of damage in cylindrical parts of carbon fiber/epoxy composites using electrical resistance (ER) measurements

“…Generally the changes in the ER signal due damage in such conductive materials has been under tensile loading [7][8][9][10].The "probes" used in the ER method need to have very good adhesion between the probes and the specimen in which the displacement are relatively small [11,12]. Flexural and compression loading, on the other hand, may produce larger shape changes and potentially unstable ER signals [13][14][15].…”

In-situ damage sensing of woven composites using carbon nanotube conductive networks

“…Various loading conditions were also investigated including tension [23], compression [24], cyclic loading [25], and impact [26], demonstrating that in-situ detecting of damages using the CNT network is reliable. Furthermore, this method was applied to textile composites such as woven [27,28], knitted [29], and braided [7] composites. In our previous work on 3-D braided composites, we reported a transition of the piezoresistive behavior from positive to negative value (i.e., electrical resistance reduced beyond a certain stain) as the deformation proceeded.…”

Strain and damage self-sensing of basalt fiber reinforced polymer laminates fabricated with carbon nanofibers/epoxy composites under tension

“…Their results reveal that the SBS/FLG fiber based strain sensor possess superior performance, including wide workable strain range (>110%), excellent sensitivity (gauge factor of 160 at a strain of 50% and of 2546 at a strain of 100%), and durability. Numerous studies have demonstrated that the combination of the ERM technique and conductive networks provided by the carbon nanomaterials surrounding the insulting fibers was an effective technique for monitoring the strain and damage of GFRP composites [29], [30], [31], [32], [33]. In the study of Li et al [29], a small amount of CNT-Al2O3 hybrids were introduced into GFRP composites to create an in-situ sensor to monitor the damage initiation and propagation under mechanical loading.…”

“…Numerous studies have demonstrated that the combination of the ERM technique and conductive networks provided by the carbon nanomaterials surrounding the insulting fibers was an effective technique for monitoring the strain and damage of GFRP composites [29], [30], [31], [32], [33]. In the study of Li et al [29], a small amount of CNT-Al2O3 hybrids were introduced into GFRP composites to create an in-situ sensor to monitor the damage initiation and propagation under mechanical loading. Their results suggested that the electrical resistance response could be classified into different distinguished stages to identify various failure modes of FRP composites.…”