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Warm deep drawing of polypropylene, a semi-crystalline thermoplastic polymer, is studied using finite element analysis. In this process, a circular polypropylene blank is preheated to a temperature much below its melting temperature and deep drawn into the shape of a flat-bottom cylindrical cup using a punch-die combination, both initially at 25[degrees]C. The material model used for the analysis considers the effects of varying temperature and strain rate during the deep drawing process on the depth of draw. The effects of blank holder force, initial blank temperature, blank diameter, and die and punch corner radii on the depth of draw are determined. Thickness, temperature, and strain variations in the drawn cups, punch forces, and failure modes are also determined. KEYWORDS deep drawing, failure modes, modeling, polypropylene, thickness distribution, 1 | INTRODUCTION Deep drawing is a well-established metal forming process [1] and is widely used with steels, aluminum alloys, and other metals in the automotive as well as nonautomotive [...]

Biodiesel is considered one of the best alternative fuel sources in the transportation industry, but rt has shown aggressive characteristics on materials that are used in fuel storage and delivery systems in vehicles. In this study, the effect of biodiesel (B100) on the properties of two polyamide-6-based semicrystalline polymers was studied and compared with that of diesel and a 20/80 blend of biodiesel and diesel (B20). Experiments were conducted using room temperature immersion tests in the three fuels for 720 h followed by postimmersion thermal and mechanical tests. In all three fuels, the polymers exhibited non-Fickian weight increase during immersion and did not achieve equilibrium level of absorption in 720 h. The glass transition temperature ([T.sub.g]), yield and tensile strengths, storage modulus, and peak tan [delta] decreased after immersion, while the degree of crystallinity and loss modulus increased. Fourier transform infrared spectroscopy study showed that no chemical changes occurred due to immersion. It is concluded that all three fuels absorbed into the polymers acted as plasticizers which caused the observed changes in the properties of the two polymers investigated in this research., INTRODUCTION Polymers are used in many fuel container and fuel delivery applications where they are exposed to or immersed in fuels that can cause degradation in their physical and mechanical [...]