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There are significant predictive tool usages by design engineers in automotive industry to capture material composition and manufacturing process-induced variables. In specific, an accurate modeling of material behavior to predict the mechanical performance of a thermoplastic part is an evolving subject in this field as one needs to consider multiple factors and steps to achieve the right prediction accuracies. The variability in prediction comes from different factors such as polymer type (filled vs. unfilled, amorphous vs semi crystalline etc.), design and manufacturing features (weldline, gate locations, thickness, notches etc.), operating conditions (temperature, moisture etc.) and finally load states (tension, compression, flexural, impact etc.). Using traditional numerical simulation-based modelling to study and validate all these factors requires significant computational time and effort.

Previous material solution for industrial inverter applications was PC/ABS for more than 10 years. Recently, PC/ABS has been reduced in the market due to customer needs for improved performance of existing materials and market trends for improved material like raising carbon credits are emphasizing the need for eco-friendly environmental technologies and rapidly growing smart factories to deliver, smart power consumption technologies for environmental protection and energy saving. This trend is rapidly changing in common life and various industries, so new material solutions are required to improve effective material solutions such as less or no outgassing, thermal stability and lower process temperature availability, color stability, better flame retardant properties and so on. In this study, according to new industry requirements, material evaluation was conducted with SABIC NORYLTM N-series PPE resins and incumbent PC/ABS material.

Usage of fiber-filled thermoplastics in automotive structural applications are increasing due to their inherent advantages over metal, which include lighter weight and simplification in assembly. However, accurately predicting the performance of a fiber-filled thermoplastic part can be challenging due to presence of non-linearity and anisotropy in the material behavior. This paper describes material characterization and modeling of fiber-filled thermoplastics for accurate prediction of part performance to enable rapid use of these lighter materials in automotive applications. The grade used for the study is a 30% glass filled PEI, SABIC’s ULTEMTM 2300 Resin. Accuracy of the fiber orientation prediction is clearly demonstrated by the plaque level flow simulation validation with the CT-Scan data, followed by structural validations with specimen and part level tests.

The emergence of thermoplastics in automotive structural parts is constantly increasing as designers recognize the benefits thermoplastics bring, such as light-weighting, cost effectiveness, the ability to integrate parts, the flexibility to design intricate shapes, and the materials’ high specific energy absorption capacity. In order to predict the behavior of plastics by simulation using finite elemental analysis (FEA) tools such as LS-DYNA®1, an extensive understanding of properties and implementation using FEA is very important. In order to obtain reliable results from simulation, the FEA solver should support material models which predict the behavior of plastics accurately. LS-DYNA® supports several material models which are used to predict behaviour of plastics, and one, the Semi-Analytical Model for Polymers (SAMP-1 with GISSMO failure), was developed exclusively for plastics.

This paper discusses the engineering design and development of a plastic automotive engine oil pump as an alternative to current metal oil pumps. Detailed component design features to ensure the working of the plastic pump under harsh chemical, temperature and vibration environment are discussed. The proposed design integrates several parts and uses unique plastic design elements to improve upon current metal design. Innovative joining methods and assembly sequencing are implemented to maintain pump efficiency and functional precision. Use of self-lubricating plastics to increase engine efficiency by reducing wear between moving parts is explored. Data and findings from extensive structural and processing simulations, as well as high temperature and long-term material tests, carried out during the design phase to ensure structural integrity and manufacturability are included.

Degradation processes driven by UV exposure, and manifested for example as polymer gloss loss or coating failure, are generally accelerated at elevated temperature, or conversely, their rates are reduced at lower temperature. In a weathering environment comprising IR irradiance, IR transmitting black resin tends to be cooler than an otherwise comparable sample of IR absorbing black resin. Accordingly, slower UV-driven degradation, and longer weathering lifetime, is expected for IR transmitting black resin relative to IR absorbing black resin, commensurate with their temperature difference in a given weathering environment and the sensitivity of the degradation process to temperature.

Polycarbonate (PC) glazing as a one-for-one glass replacement offers a 50% weight reduction, but exhibits several dB lower sound transmission loss (STL) in the low frequency range where tire and engine noise are dominant. In the high frequency range where wind noise is dominant, PC glazing offers an STL at least comparable to its glass counterpart, and an STL exceeding glass when this frequency range encompasses the glass coincidence frequency. However, a key value proposition of PC glazing is the opportunity for feature integration afforded by the injection molding process generally used for forming such glazing. Two-component (2K) molding fuses a second shot of plastic material behind, and along the perimeter of, the transparent PC first shot. This second shot can incorporate features and implement functions that require additional components attached or peripheral to a glass version.

Fogging (i.e. condensation of water vapor) in headlamps in severe weather conditions present both a performance and potential safety concern for automotive companies. Conventional headlamps are based on incandescent bulbs. In recent times, LED lighting has increasingly become the norm. However, LED based headlamps are prone to higher levels of fogging because they inherently produce less heat than the conventional incandescent or halogen bulbs. A headlamp design must be able to dispose all the formed condensate/fog in a fixed time even under severe thermal conditions. It is of great importance for the car manufacturer to be able to simulate the risk of condensation early in the design stage with an eye on the overall cost reduction. The combined use of experimental studies and numerical modelling is important to optimize headlamp design and to produce high-performance headlamps.

Automotive OEMs, insurance agencies and regulatory bodies are continuously looking at various accident statistics and proper ways of evaluating unaccounted (as per current regulations and safety ratings) accident scenarios to improve the safety standards of cars. Small overlap and oblique impacts during which a corner of a car hits a tree or the corner of another vehicle are two such situations. Most of the vehicles that are on road scored low when tested for these impact scenarios. This paper focuses on development of energy-absorbing members, using engineering thermoplastics materials, which can be mounted on the BIW of a vehicle, as countermeasures to small overlap impact. Various design and material configurations options, including metal plastic and composite plastic structural members mounted on the BIW are evaluated through CAE studies, against small overlap/oblique impact scenarios.

With a significant increase in awareness of safety and sustainability among the automobile original equipment manufacturers and end users, every car manufacturer is looking for lightweight, safe and cost-effective solutions for every unit present in their vehicle. The latter gets much more focus in developing countries, where the automobile market is extremely cost sensitive. Further, with implementation of the proposed global technical regulations on pedestrian safety in the near future and low-speed vehicle damageability requirements, demand for a low-cost, lighter and safer bumper system is ever increasing. This paper focuses on development of a unique thermoplastic energy-absorbing device for vehicle bumpers. Conventionally, major energy absorbing members of these bumper systems consist of three separate pieces: energy absorber, bumper beam and crash cans. A hybrid approach based on logical reasoning and topology optimization is used to conceive the design.

Coated polycarbonate (PC) is a leading engineering thermoplastic used in automotive glazing for replacing laminated glass. Mechanical properties of multi-layer coating systems were investigated using a nano-indenter and the fracture behavior of coating during nano-scratch was studied employing scanning electron and atomic force microscopy. A set of coated samples was prepared, with two layers, namely Layer-1 and Layer-2. Layer-1 was applied directly to the PC substrate and used as adhesion promoter. Layer-2 was prepared with different mechanical properties. Abrasion performance of the coated system was characterized using an ASTM abrasion test methodology. Regression analysis was performed to establish correlation between the mechanical properties of the coating system and its abrasion performance. Fracture behavior of the coating systems and their plausible relationship with abrasion performance was also discussed.