This document provides an overview of mechanical property evaluation of natural fiber reinforced polymers. It discusses how natural fibers like jute, sisal and hemp can be used to reinforce polymers, giving composites with good mechanical properties. The mechanical properties discussed include tensile, flexural and impact properties. The document also outlines some applications of natural fiber composites in areas like construction, automotive and packaging industries. In conclusion, it states that natural fiber composites possess good mechanical properties and can be used in different applications.

1. An Overview on Mechanical Property Evaluation of Natural
Fiber Reinforced Polymers
A Seminar Presented by
Abhishek Chaturvedi
17ME002
Subject – Seminar 2ME694
M.Tech (Production Engineering)
Mechanical Engineering Department
National Institute of Technology Patna
Bihar 800005
Under the Supervision of
Dr. Kuntal Maji

2. ABSTRACT
This article presents an overview of the mechanical properties like
tensile, flexural, impact, fracture surface observations and corresponding
modulus of elasticity of natural fiber reinforced polymer composites.
Natural fibers have recently become attractive to scientists and
researchers as good alternative for fiber reinforced composites because
of their low cost, non-abrasive and eco-friendly nature. Natural fibers
may play an important role in developing biodegradable composites to
resolve the current ecological and environmental problems. In
connection with brief overview has been carried out on natural fibers
because these are abundantly available in India. This article shows that
the natural fibers are also possesses good mechanical properties and
these fiber composites can also be used in different applications.

3. A composite is a structural material that consists of two or more
combined constituents that are combined at a macroscopic level and are
not soluble in each other. One constituent is called the reinforcing phase
and the one in which it is embedded is called the matrix. The reinforcing
phase material may be in the form of fibers, particles, or flakes. The
matrix phase materials are generally continuous. Fiber reinforced
polymer materials are composites consisting of high strength fibers
(reinforcement) embedded in polymeric matrices. Fibers in these
materials are the load-carrying elements and provide strength and
rigidity, while the polymer matrices maintain the fibers alignment
(position and orientation) and protect them against the environment and
possible damage. A pure polymer does not usually have the requisite
mechanical strength for application in various fields.
INTRODUCTION

4. Natural fibres as an alternative reinforcement in polymer composites
have attracted the attention of many researchers and scientists due to
their advantages over conventional glass and carbon fibres. These natural
fibers include flax, hemp, jute, sisal, coir, kapok, banana, henequen and
many others. These composites materials are suitably applicable for
aerospace, leisure, construction, sport, packaging and automotive
industries, especially for the last mentioned application. The various
advantages of natural fibres over man-made glass and carbon fibres are
low cost, low density, comparable specific tensile properties, nonabrasive
to the equipment, nonirritating to the skin, reduced energy consumption,
renewability, recyclability and biodegradability. In general, the tensile
strengths of the natural fibre reinforced polymer composites increase
with fibre content, up to a maximum or optimum value, the value will
then drop. However, the Young’s modulus of the natural fibre reinforced
polymer composites increase with increasing fibre loading.
Fiber Reinforced Polymer
Composites

5. The strength and stiffness of plant fibers depend on the cellulose content
and the spiral angle which the bands of micro fibrils in the inner
secondary cell wall make with the fibre axis. That is, the structure and
properties of natural fibres depend on their source, age, etc. The structure
and properties of the natural fibre itself, experimental conditions such as
fibre length, test speed etc., all have some effects on the properties of
natural fibres. It has been reported by several authors that modification
of fibres improved the mechanical properties of composites. From the
Rule of Mixtures theory, the approximate composite modulus can be
obtained from a modified Rule of Mixtures as: Ec =EfVf + EmVm Where
Ec, Ef & Em are young’s modulus of composites, fiber and matrix
respectively and Vf & Vm are volume fraction of fiber and matrix
respectively.
Mechanical Properties of Natural Fiber
Reinforced Polymer Composites

6. Tensile Properties of Natural Fibers

7. Flexural Properties of Natural Fibers

8. Composites made of natural fibers offer the opportunity for extensive
applications in fields such as consumer goods, low cost housing and civil
structures, and for many other common applications. The cement
composites reinforced by bamboo pulps are produced by the vacuum
pressure process, seeking to establish the characteristics of a material
which can be easily fabricated, utilizing the machinery of asbestos
cement industry. The bamboo pulp is used in the paper industry on a
large scale. There are studies underway to produce durable furniture and
new geometrical structural forms, as well as bicycles, tricycles and car
bodies using bamboo. The kenafbast fibre is used for bags, cordage, and
the sails for Egyptian boats. The uses of kenaf fibre have been rope,
twine, insulation, clothing-grade cloth, soil-less potting mixes, animal
bedding, packing material and material that absorbs oil and liquids. Jute
is used as packaging material (bags), carpet, backing, ropes and
yarns.The Sisal fibres are found commercially in several formats: fabric,
cords, strips,wire, rolls, etc.
APPLICATIONS

9. The mechanical property of natural fibres varies from fibre to fibre. The
mechanical properties of fiber depend on type of fibre, origin age,
volume fraction physical properties, structure, environmental conditions
and processing methods. Different matrix systems have different
properties. Natural fibres have well prospective as reinforcements in
polymer composites. Due to high specific properties and low density of
natural fibres, composites based on these fibres may have very good
implications in industries. From this review newer composite using
abundantly available natural fibres brings new trends in composite
materials. This article shows that the natural fibers are also possesses
good mechanical properties and these fiber composites can also be used
in different applications.
CONCLUSION

10. 1. Coutinho F M B, Costa T H S (1999). Polym. Test 18(8), pp.581-587.
2. Saheb D N, Jog J P (1999). Adv. Polym. Technol 18(4), pp.351- 363.
3. Bettini S H P, Uliana AT, Holzschuh D J (2008). J. Appl. Polym. Sci
108, pp.2233-2241.
4. Malkapuram R, Kumar V, Yuvraj S N, (2008). Journal of Reinforced
Plastics and Composites, Vol. 28, pp.1169-1189.
5. Li X, Tabil L G, Panigrahi S, Crerar W J (2009). Canadian Biosystems
Engineering, 08-148, pp. 1-10.
6. Wambua P, Ivens J, Verpoest I (2003). Composites Science and
Technology, Vol. 63, pp.1259-1264.
7. H Ku, H Wang, N Pattarachaiyakoop, M Trada (2011). Composites:
Part B 42, pp.856–873.
8. Mariana Etcheverry, Silvia E. Barbosa. Materials 2012, 5, 1084-1113.
9. Mallick P K (1997). Marcel Dekker Inc.: New York, NY, USA.
REFERENCES

11. THANK YOU !