Low Velocity Impact Behavior of Glass Filled Fiber-Reinforced Thermoplastic Engine Components
This paper concerns automotive parts located underneath the engine and in particular the engine oil pan. Classically made of stamped steel or cast aluminum, new developments have allowed the manufacture oil pans with polyamide 66 reinforced by 35% weight of short glass fiber. However, polyamides have some limitations and the most significant is their response to localized impact loading. The nature of the impact considered here is of a typical stone collected from the road and projected into the oil pan. Low velocity impact investigations were carried out using a gas gun and drop weight tower. The study shows that the design of the oil pan has a significant contribution in the shock absorption. In addition to the material properties, the geometry and the ribbing both cleverly combined, increase the impact resistance of the component significantly. Areas of oil pan design improvement have been identified and conclusions drawn.
Finite Element Analysis of Glass Fiber‐Reinforced Polyamide Engine Oil Pan Subjected to Localized Low Velocity Impact from Flying Projectiles
This paper investigates low velocity impact involving a glass fiber‐reinforced polyamide engine oil pan as part of a complete new development of thermoplastic components. The assessment of the impact resistance has driven the need to employ LS DYNA for finite element modeling in order to benchmark and predict the strength and fracture behavior of stressed plastic parts. In order to develop a reliable predictive capability and to validate simulations, complete components were manufactured by injection molding techniques for the experimental samples. Low velocity impact investigations were carried out using a gas gun and a falling weight tester in order to simulate impact events to which the oil pan is subjected whilst in operational service. This was intended to point out damage tolerance and failure mechanisms likely to occur in the structure. The study results show the significant contribution of the design in terms of shock absorption. Specific oil pan design with protective ribbing combined with a superior material considerably improves the impact resistance. The paper provides results and discussions on experimental and finite element analysis investigations before concluding with some remarks.
Transverse Impact Behavior of Knitted Carbon-Fiber Fabric-Reinforced Thermoplastic Composite Sheets
Instrumented falling weight impact (IFWI) properties of two-dimensional (2D) weft-knitted carbon-fiber (CF)-reinforced poly(ethyl methacrylate) (PEMA) and poly(ether ether ketone) (PEEK) composites with a reinforcement content of V f≈ 35 and 51 vol.%, respectively, were studied under low-energy and perforation impact conditions. Results indicated that the transverse impact response of these thermoplastic composites strongly depends on the ductility of the matrix, on fiber/matrix adhesion, and on the stitch (rib) structure (size, stretching of the fabrics) of the knitted fabric reinforcement. The highest thickness-related perforation impact energy was found for the knitted CF-reinforced PEEK composite (≈15 J/mm) due to its high reinforcement content, high matrix ductility, and good fiber/matrix bonding.