IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE) e-ISSN: 2278-1684, p-ISSN: 2320-334X PP 38-42 www.iosrjournals.org International Conference on Advances in Engineering & Technology – 2014 (ICAET-2014) 38 | Page Study of tribological properties of ABS / CaCO 3 polymer composites using Taguchi method J Sudeepan 1 , K Kumar 2* , T K Barman 3 , P Sahoo 3 1 Department of Chemical Engineering & Technology, BIT, Mesra, India 2 Department of Mechanical Engineering, BIT, Mesra, India 3 Department of Mechanical Engineering, Jadavpur University, Kolkata, India ABSTRACT: In this paper, acrylonitrile – butadiene – styrene (ABS) with different compositions of micron- sized CaCO 3 , composite material is prepared by compression moulding through melt compounding. The tribological properties (friction and wear depth) of the polymer composites are investigated in a multi-tribo- tester using block-on-roller configuration in dry sliding conditions for a time of 300 seconds at ambient temperature. Experiments are conducted based on L 27 orthogonal array considering three design parameters viz. filler content, normal load and sliding speed. The experimental data are analysed using Taguchi method. Optimal settings of the process parameters are found out for coefficient of friction and wear depth. ANOVA is carried out to obtain the significant factors affecting friction and wear depth. It is seen that normal load is the main significant factor affecting wear at 95% confidence level. Confirmation tests for coefficient of friction and wear are carried out to validate the optimized results and it is seen that there are improvements in S/N ratios from initial to optimal setting. Finally, the wear tracks of the composite are observed on a scanning electron microscope (SEM). Keywords: Composite material, Friction coefficient, Optimization, Taguchi method, Wear depth. I. INTRODUCTION Nowadays polymers are widely used in various tribological components due to the advantage of self- lubrication. But polymers alone cannot satisfy the required properties for tribological applications. Thus, in order to improve properties and to lower the cost of polymer products, inorganic particulate fillers are employed. ABS (Acrylonitrile – butadiene – styrene) is a well known engineering thermoplastic terpolymer over the past decades. The acrylonitrile gives chemical resistance and heat stability, butadiene gives toughness and impact strength and the styrene gives rigidity and easiness of processability. Inorganic particulate fillers of micrometer-sized particles can improve modulus, hardness and fracture toughness but at the cost of reduced impact strength and tensile strength in the polymer composites [1-4]. Polymer composites can be effective if the right combination of filler with matrix and the suitable production process are used in order to achieve the special properties [5]. In particular, polymers containing fillers have been widely used in various applications. But there has been little investigation on the development of ABS polymer with micro-sized CaCO 3 conventional filler for tribological applications. Most of the literatures are based on the mechanical properties of ABS / CaCO 3 composites. Jiang et al. [2] found that micron sized filler is more effective in terms of modulus than nano-sized CaCO 3 . Tang et al. [3] and Liang [4] have studied tensile, impact and bending properties of CaCO 3 and hollow glass bead filled ABS. For injection molded specimens, the tensile modulus increases with increase in the ratio of fillers and tensile strength decreases gently with the increase of filler. Difallah et al. [5] observed that the tensile modulus and strength decrease but friction decreases with an increase in content of graphite for ABS/graphite composite. Shenavar et al. [6] have reported that modulus increases and yield stress decreases by increasing the carbon black loading. Henshaw et al. [7] and Chuyjulijit and Ketthongmongkol [8] have reported that the injection moulded specimens exhibit good mechanical properties like tensile strength and elongation at break. In order to improve the wear resistance, various kinds of fillers such as TiO 2 , ZrO 2 , CuO, CuS, CaCO 3 are used with various polymers [9-10]. From the review of literatures, it is seen that ABS / CaCO 3 composites have received limited attention compared to other engineering thermoplastics in the tribological field. The present study is focussed on the tribological behaviour of ABS / CaCO 3 composites. The friction and wear performance of the polymer composites are investigated under different filler content, normal load and sliding speed with the constant time of 300 seconds based on L 27 orthogonal array. The experimental data is analysed using Taguchi method to find the optimal setting of the process parameters for minimum wear and friction. Also, ANOVA is carried out to obtain the significant factors affecting wear and friction. Confirmation tests are carried out to validate the study. Finally, an effort is made to study the morphology of wear tracks after the tribological tests using SEM images.