Fatigue Life Estimation of an Elastomeric Pad by ε-N Curve and FEA

Baban Suryatal¹, Haribhau Phakatkar², Kasilingam Rajkumar³, Ponniah Thavamani³

¹Department of Mechanical Engineering, PDEA’s College Engineering, Manjari (Bk.), Pune, India.
²Department of Mechanical Engineering, Vishwakarma Institute of Technology, Pune, India.
³Indian Rubber Manufacturer’s Research Association, Thane (W), India.

DOI: 10.4236/jsemat.2015.52010                

Abstract

Failure analysis and fatigue life prediction are very important in the design procedure to assure the safety and reliability of rubber components. The fatigue life of a railway elastomeric pad is predicted by combining the test of material properties and finite element analysis (FEA). The specially developed chloroprene rubber material’s fatigue life equation is acquired based on uniaxial tensile test and fatigue life tests performed on the dumbbell specimens of the chloroprene rubber. The same chloroprene rubber was developed at Indian Rubber Manufacturer’s Research Association, Thane. The strain distribution contours and the maximum total principal strains of the elastomeric pad at different compressive loads are obtained using finite element analysis method. The software used for the FEA was ANSYS. The three parameter nonlinear hyperelastic Mooney-Rivlin Model and plane 182 elements were used for finite element analysis. The critical region cracks prone to arise are obtained and analysed. Then the maximum first principal elastic strain was used as the fatigue damage parameter, which is substituted in the chloroprene rubber’s fatigue life equation, to predict the fatigue life of an elastomeric pad in the number of cycles at different compressive loads. The results were compared with the technical requirements given by Indian Railway’s Research Designs and Standards Organization. These requirements were achieved up to certain extents. The results were also compared with the data available in the literature and a similarity was observed between the results acquired and literature data. In short, the proposed fatigue life prediction method can shorten the product design cycle, decrease the design and product cost remarkably and improve the quality of an elastomeric pad.

Keywords

Elastomeric Pad, Fatigue Life, Finite Element Analysis (FEA), Fatigue Life Equation, Total Principal Strain, Chloroprene Rubber

Conflicts of Interest

The authors declare no conflicts of interest.

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