Title: Mechanical properties of banana fibres (Musa sepientum)
Abstract: The stress—strain curve for banana fibre is determined. Properties such as the initial modulus (YM), ultimate tensile strength (UTS) and percentage elongation are evaluated as a function of fibre diameter, test length and speed of testing. It is found that YM, UTS and % elongation show little variation in their values for fibres of diameter ranging from 50 to 250 μm. The UTS and breaking strain are found to decrease with an increase in the test length while both breaking strength and breaking strain remain constant with the increase of speed of testing from 0.5 to 100 × 10−3 m and thereafter they both decrease. These observed properties are explained on the basis of the internal structure of the fibre, namely, the number of cells, spiral angle and the number of defects. Scanning electron microscopic (SEM) studies of the fractured surfaces of these fibres indiacte that the failure is due to pull-out of microfibrils accompanied by tearing of cell walls; the tendency for fibre pull-out seems to decrease with increasing speed of testing.