Download or read book Numerical and Experimental Investigation of Nylon66 PA66 Reinforced Recycled Carbon Fiber Composites and Aluminum Foam for Application in Vehicle Crashworthiness and Occupant Protection Per Various FMVSS Regulations written by Tharun R. Chillakuru and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the past decade, there has been an increase in the usage of advanced composite structures and metal foam filler materials for a wide range of applications in the automotive industry, primarily due to their correct strength, stiffness, and energy absorption. In addition, these materials offer high impact resistance compared to traditional metals and foam materials like PU/IMPAXX. However, due to the destructive nature of the crashes, the costs involved in testing physical car models are escalating every year. For this reason, numerical simulations, particularly Finite Element Analysis (FEA), significantly lower the costs associated with physical model testing. The goal of this research is to investigate two different engineered materials; namely Nylon66 reinforced recycled carbon fiber (PA66 RCF), and aluminum metal foam, for crashworthiness applications. To achieve this goal, it is essential to have a library of mechanical properties with materials of interest. Firstly, the coupon level tests such as tensile, three-point bending, and compression are performed. The experimental test data is numerically validated to have a working and scalable LS-DYNA material card for the component level and full-scale simulations. Secondly, the component level simulations are performed on empty thin-wall square PA66 RCF tubes and aluminum foam-filled tubes to understand the compressive behavior of the materials and later compared against the empty thin-wall and aluminum foam-filled steel square tubes. Finally, full-scale dynamic simulations are performed according to the federal motor vehicle safety standards (FMVSS) NO.208, NO.214, NO.301R, and NO.216a using the LS-DYNA FE code. The materials are utilized in various regions of the vehicle including the front bumper, side driver door, rear bumper, and roof panel of a compact sedan finite element model. This study quantifies deceleration loads, energies, and compartment intrusion. It is demonstrated that applying PA66 RCF and foam materials significantly reduce compartment loads and intrusions. Therefore, both materials are shown to exhibit promising results in improving vehicle crashworthiness and occupant protection of ground vehicles.

Download or read book Automotive Crashworthiness of Adhesively Bonded Carbon Fiber Polymer Composite Structures written by and published by . This book was released on 2006 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: In passenger vehicles, the ability to absorb impact energy and be survivable for the occupant is called the "crashworthiness" of the structure. The ACC (Automotive Composite Consortium) has been and continues to be very interested in investigating the use of fiber-reinforced composites as crash energy absorbers. It would have been ideal if the composite structure to be used as a crash energy absorber were manufactured as an integral, monolithic component, but limitations in the present day manufacturing technology necessitate the presence of joints in composite structures. While many scientists have investigated the energy absorption characteristics in various fiber reinforced composite materials, there is no literature available on the energy absorption and crushing characteristics of these materials when they are used in a bonded structure. The influence of having a bonded joint within the crush zone of a composite structure has not been adequately characterized in the past. After reviewing the existing literature and based on our own work done in automotive crashworthiness studies it can be concluded that investigating the strain rate dependence of fiber reinforced polymer composites and bonded structures made from them are also very important since the amount of energy they absorb and their performance properties vary with loading rate. The above is the last stage in crashworthiness research, where in one would like to determine how best fiber composite structures can be bonded together in the pursuit of designing the most crashworthy adhesively bonded automotive composite structure. Hence, a comprehensive experimental methodology to analyze and design adhesively bonded automotive composite structures made of carbon fiber polymer composites to sustain axial, off-axis and lateral crash/impact loads is developed and strain rate effects on the crashworthiness of these bonded carbon fiber composite structures are studied. The experimental results from this work are being used to provide the building blocks for model developments - first the coupon level, then progressing in complexity to component level. Correlation with experimental results will provide the basis for which the analytical developments including development of constitutive laws, materials models, damage algorithms and new finite elements, are made.