1Department of Applied Mechanics, Motilal Nehru National Institute of Technology (Deemed university), Allahabad-211004, INDIA. E-mail:
2Department of Mechanical Engineering, V.B.S Poorvanchal University, Jaunpur, INDIA. E-mail:
Palmyra fiber is obtained from the palmyra (palm) tree, which is 10 to 15 metre high plant. If used as reinforcing constituent in some matrix, it will result in a cost-effective and eco-friendly composite. Palmyra fibre is easily and abundantly available in India, Srilanka, etc. It is not only cheaper but also possesses high specific strength and modulus. Due to its low specific weight, it can be a better alternative to existing synthetic fibre reinforced composites.
In this work, the raw palmyra fibres (botanical name is boralessus flabellifer) have been extracted from the tissues of primary stem of palm (toddy) plant, processed, prepared, and tested to determine their physical and mechanical properties. Ten individual fibres have been tested in natural (usually wet) condition and straight configuration. Density of different individual fibres of 200 mm length having mean diameter of 0.20 to 0.21 mm, and weight varying from 0.018 gm to 0.022 gm is obtained SIt varies from 606.7 kg/m3 to 789.3 kg/m3 (i.e. 0.606 gm/cm3 to 0.789 gm/cm3).
The tensile tests have been performed on Hounsfield tensometer using a scale of 0–30 kg (0–300 N) with a least count of 0.2 kg (2 N). Different fibres of 0.42 mm to 0.60 mm diameter have sustained widely varying maximum load of 1.2 kg to 2.2 kg (12 N to 22 N) and have undergone an elongation of 8 mm to 20 mm.The recorded strains vary from 0.082 to 0.189. The tensile strength is found to vary from 500 kg/cm2 to 1923 kg/cm2 (50 MPa to 192.3 MPa).The stress-strain behaviour is plotted in figures. Its nature is widely varying from linear to non-linear. The cause of variation in properties of different fibres is their different age and growth.
Finding of this work has been compared with other natural fibres like flax, hemp, jute, coir, sisal and cotton. It is concluded that the density of palmyra is least among all known fibres. It is 0.7 only as compared to 1.25 for coir, 1.33 for sisal, 1.40 for flax, 1.46 for jute, 1.48 for hemp and 1.51 for cotton fibres. This is highly favourable property from the view point of lightweightness. Hence, the palmyra fibres are most suitable for making reinforcement in composite materials.
Palmyra fibre, natural reinforcing material, testing of individual fibre, tensile strength, density determination, lightweight fibre
