%0 Journal Article
%T Effect of Short Fiber Reinforcement on Mechanical Properties of Hybrid Phenolic Composites
%A Sembian Manoharan
%A Bhimappa Suresha
%A Govindarajulu Ramadoss
%A Basavaraj Bharath
%J Journal of Materials
%D 2014
%I Hindawi Publishing Corporation
%R 10.1155/2014/478549
%X Fiber plays an important role in determining the hardness, strength, and dynamic mechanical properties of composite material. In the present work, enhancement of viscoelastic behaviour of hybrid phenolic composites has been synergistically investigated. Five different phenolic composites, namely, C1, C2, C3, C4, and C5, were fabricated by varying the weight percentage of basalt and aramid fiber, namely, 25, 20, 15, 10, and 5% by compensating with barium sulphate (BaSO4) to keep the combined reinforcement concentration at 25£¿wt%. Hardness was measured to examine the resistance of composites to indentation. The hardness of phenolic composites increased from 72.2 to 85.2 with increase in basalt fiber loading. Composite C1 (25£¿wt% fiber) is 1.2 times harder than composite C5. Compression test was conducted to find out compressive strength of phenolic composites and compressive strength increased with increase in fiber content. Dynamic mechanical analysis (DMA) was carried out to assess the temperature dependence mechanical properties in terms of storage modulus ( ), loss modulus ( ), and damping factor (tan ¦Ä). The results indicate great improvement of values and decrease in damping behaviour of composite upon fiber addition. Further X-ray powder diffraction (XRD) and energy-dispersive X-ray (EDX) analysis were employed to characterize the friction composites. 1. Introduction The brake system of an automobile is an inevitable safety aspect, which stops the vehicle quickly and reliably under varying conditions. Nowadays nonasbestos organic (NAO) friction materials are mainly used in automotive brake linings and it is a mixture of four classes of ingredients, namely, binder, reinforcements, fillers, and friction modifiers [1, 2]. Among these ingredients, organic binder (phenol formaldehyde) plays a crucial role in determining the characteristics of material during braking and holds all other ingredients together. Fibers (mineral, aramid, glass, carbon, ceramic, and steel wool) are used to improve the strength of composite, while fillers are mainly used to bring down the cost and act as lubricants and abrasives to control wear rate of the composite. This multicomponent nature of friction composite helps the brake lining material to withstand very high pressure and thermal stresses and contribute to an effective braking performance [3, 4]. The fiber reinforcement is proved to be potentially promising on tribological properties and forms the basis for formulating the brake friction material. Basalt is a kind of alumina silicate fiber composed of many oxides with
%U http://www.hindawi.com/journals/jma/2014/478549/