Design, Analysis, Fabrication And Testing Of A Composite Leaf Spring

Started by aruljothi, Sep 11, 2008, 11:33 AM

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In order to conserve natural resources and economize energy, weight reduction has been the main focus of automobile manufacturers in the present scenario. Weight reduction can be achieved primarily by the introduction of better material, design optimization and better manufacturing processes. The suspension leaf spring is one of the potential items for weight reduction in automobiles as it accounts for 10% - 20% of the unsprung weight. This achieves the vehicle with more fuel efficiency and improved riding qualities.

The introduction of composite materials was made it possible to reduce the weight of leaf spring without any reduction on load carrying capacity and stiffness. Since, the composite materials have more elastic strain energy storage capacity and high strength to weight ratio as compared with those of steel, multi-leaf steel springs are being replaced by mono-leaf composite springs. The composite material offer opportunities for substantial weight saving but not always be cost-effective over their steel counterparts.

Literature Review

Investigation of composite leaf spring in the early 60's failed to yield the production facility because of inconsistent fatigue performance and absence of strong need for mass reduction. Researches in the area of automobile components have been receiving considerable attention now. Particularly the automobile manufacturers and parts makers have been attempting to reduce the weight of the vehicles in recent years. Emphasis of vehicles weight reduction in 1978 justified taking a new look at composite springs. Studies are made to demonstrate viability and potential of FRP in automotive structural application.

The development of a liteflex suspension leaf spring is first achieved. Based on consideration of chipping resistance base part resistance and fatigue resistance, a carbon glass fiber hybrid laminated spring is constructed. A general discussion on analysis and design of constant width, variable thickness, composite leaf spring is presented. The fundamental characteristics of the double tapered FRP beam are evaluated for leaf spring application. Recent developments have been achieved in the field of materials improvement and quality assured for composite leaf springs based on microstructure mechanism. All these literature report that the cost of composite; leaf spring is higher than that of steel leaf spring. Hence an attempt has been made to fabricate the composite leaf spring with the same cost as that of steel leaf spring.

Material properties and design of composite structures are reported in many literatures. Very little information are available in connection with finite element analysis of leaf spring in the literature, than too in 2D analysis of leaf spring. At the same time, the literature available regarding experimental stress analysis more. The experimental procedures are described in national and international standards. Recent emphasis on mass reduction and developments in materials synthesis and processing technology has led to proven production -worthy vehicle equipment.

Materials Selection

Materials constitute nearly 60%-70% of the vehicle cost and contribute to the quality and the performance of the vehicle. Even a small amount in weight reduction of the vehicle, may have a wider economic impact. Composite materials are proved as suitable substitutes for steel in connection with weight reduction of the vehicle. Hence, the composite material have been selected for le


Hello All,

Well as Arun have rightly mentioned about the weight reduction of vehicles due to composite leaf springs, want to share few more advantages ......

Plz note : Highest Tolerable Vibration for Human body is 1.5 hertz (As per International standards)

               Metal Leaf Spring— 1.10 Hz
               ARC Leaf Spring — 0.35 Hz

Advantages of ARC Composite carbon fiber leaf spring suspension:

1) Specifically made to give effects like Air Suspension with out any extra external energy(Fuel)

2) No permanent deformation hence no re-cambering, thus no maintenance.

3) Minimum wear and tear of body parts and tyre due to delicate tendency of absorbing road shocks, jerks and vibrations.

4) Softer ride, Lower noise level, excellent stability due to better damping characteristics.

5) Excellent corrosion resistance against atmospheric pollutants.

6) Five times stronger than conventional metal leaf springs.

7) Fully interchangeable with the conventional spring without any modifications.

8) Increase in fuel efficiency due to better aerodynamics and around 60% weight reduction.

9) No cracking sound since mono leaf and hence no inter-leaf friction and no greasing required.

10) Fatigue life 1 million cycles as compared to only 2 lacs for the metal leaf springs. ( ARAI tested)

                    Will keep you all updated about these CLF's and  benefits/advantages of composite leaf springs.

Tushar Pawar

+91 9960809010/ +91 9011022861


The properties of materials and design of composite structures have been reported in many literatures. Very little information is available in conjunction with finite element analysis of the leaf spring in the literature for 2D analysis of the leaf spring. Literature analysis of experimental constraints available on more experimental procedures are described in the national and international standards.


Materials and design of composite structures have been reported in many literature. Very little information is available in conjunction with finite element analysis Journal of literature, 2D analysis of the spring leaf spring. Literature analysis of experimental constraints available in most experimental procedures are presented in national and international standards.


Very little information available in connection with the final elements analysis of leaf Spring in the literature, rather than too in the 2D analysis of spring leaves. At the same time, the available literature on experimental stress analysis. Experimental procedures are described in the national and international standards.

Liteflex Owner

My company Liteflex LLC manufactures composite leaf springs in Dayton and Englewood Ohio USA.  Liteflex LLC has made over 20 million springs and has an installed capacity of 2 million springs per year.  With the great interest in composite leaf springs, and Liteflex LLC having the best product being made at the lowest cost, we have decided to search for partners wishing to become licensed to use the Liteflex LLC process.  $5 million molding machines are available which produce on 5 days 360,000 springs per year.  If one becomes licensed, the partner can be in production in less than 6 months.

Please contact myself the owner John Prikkel PE