Effect of Cooling Medium on Fracture Toughness of Rotomoulded Product

Abstract:

In day-to-day life, usage of plastics is numerous. It offers variety of benefits compared to other materials in various sectors like house hold applications, agricultural industry, and packaging, etc. There are numerous methods for processing plastics. These include: blow moulding, injection moulding, rotational moulding, transfer moulding and thermoforming. Rotational moulding is a competitive alternative to other plastic manufacturing process, since it offers designers an opportunity to achieve an economic production of stress free products. Many products made by rotational moulding process using linear low density polyethylene (LLDPE) are widely used in outdoor applications such as boats, over head tanks, and car body parts etc. In such applications, fracture properties are considered to be critical from the quality characterization point of view. Selection of appropriate cooling medium plays vital role to enhance the quality of rotomolded products. In this paper, an attempt has been made to investigate the effect of cooling medium on fracture toughness of the rotationally moulded products. Fracture tests are carried out on a compact tension (CT) test specimens prepared as per the ASTM D 6068 (2012). The tests are performed on a universal testing machine. R-curve method is used to determine the fracture toughness (J_IC) of rotomoulded products. From the experimental results it is found that rapid cooling method favours better fracture toughness of rotomoulded products. Therefore, it is recommended to use faster cooling aids like water cooling in rotational moulding process to achieve highest fracture toughness.

• Periodical: Applied Mechanics and Materials (Volume 852)
• Pages: 85-90
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.852.85
• Online since: September 2016
• Authors: P.L. Ramkumar*, D.M. Kulkarni, Vikas V. Chaudhari
• Keywords: Fracture Toughness, LLDPE, Plastics, Rotational Moulding

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