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On the path to decarbonizing road transport, electric commercial vehicles will play a significant role. The first applications were directed to the smaller trucks for distribution traffic with relatively moderate driving and range requirements, but meanwhile, the first generation of a complete portfolio of truck sizes is developed and available on the market. In these early applications, many compromises were accepted to overcome component availability, but meanwhile, the supply chain can address the specific needs of electric trucks. With that, the optimization towards higher usability and lower costs can be moved to the next level. Especially for long-haul trucks, efficiency is a driving factor for the total costs of ownership. Besides the propulsion system, all other systems must be optimized for higher efficiency. This includes thermal management since the thermal management components consume energy and have a direct impact on the driving range.

Thermo-mechanical fatigue and natural aging due to environmental conditions are difficult to simulate in an actual test with the advanced fiber-reinforced composites, where their fatigue and aging behavior is little understood. Predictive modeling of these processes is challenging. Thermal cyclic tests take a prohibitively long time, although the strain rate effect can be scaled well for accelerating the mechanical stress cycles. Glass fabric composites have important applications in aircraft and spacecraft structures including microwave transparent structures, impact-resistant parts of wing, fuselage deck and many other load bearing structures. Often additional additively manufactured features and coating on glass fabric composites are employed for thermal and anti-corrosion insulations. In this paper we employ a thermo-mechanical fatigue model based accelerated fatigue test and life prediction under hot to cold cycles.

In order to study the tire friction characteristics under wet skid surface, the “pseudo” hydrodynamic pressure bearing effect is used to be equivalent to the hydrodynamics of water film, and an advanced Lugre tire hydroplaning dynamic model is developed by combining the arbitrary pressure distribution function. The water hydroplaning dynamic tests were carried out for 285/70R19.5 tire under wet of different water film thickness and dry conditions, and the parameters of the advanced Lugre tire dynamic model were identified. The results show that the tire water-skiing model proposed in this paper can effectively simulate the friction characteristics of tires under different water film thicknesses. Under dry conditions, 0.5mm water film and 1mm water film road conditions, the relative errors of the maximum tire friction coefficient between the tested and advanced Lugre tire model are 1.11%, 0.12% and 0.16%, respectively.

Polymer electrolyte membrane (PEM) fuel cells will play a crucial role in the decarbonization of the transport sector, in particular for heavy duty applications. However, performance and durability of PEMFC stacks is still a concern especially when operated under high power density conditions, as required in order to improve the compactness and to reduce the cost of the system. In this context, the optimization of the geometry of hydrogen and air distributors represents a key factor to improve the distribution of the reactants on the active surface, in order to guarantee a proper water management and avoiding membrane dehydration.

The Insurance Institute for Highway Safety (IIHS) introduced its updated side-impact ratings test in 2020 to address the nearly 5,000 fatalities occurring annually on U.S. roads in side crashes. Research for the updated test indicated the most promising avenue to address the remaining real-world injuries was a higher severity vehicle-to-vehicle test using a striking barrier that represents a sport utility vehicle. A multi-stiffness aluminum honeycomb barrier was developed to match these conditions. The complexity of a multi-stiffness barrier design warranted research into developing a new dynamic certification procedure. A dynamic test procedure was created to ensure product consistency. The current study outlines the process to develop a dynamic barrier certification protocol. The final configuration includes a rigid inverted T-shaped fixture mounted to a load cell wall. This fixture is impacted by the updated IIHS moving deformable barrier at 30 km/h.

Rotary Bell Atomizers are well established in the automotive industry for top coating applications. This type of atomizer allows to create a uniform coating and is characterized by high productivity. Meanwhile, the effectiveness of the process depends on many complex factors. For instance, the transfer efficiency of the paint material, which is the percentage of the paint reaching the structure surface, ranges from 60-95% depending on the application conditions. Any increase in the transfer efficiency can not only reduce energy and material costs, but also reduce the emission of harmful non-deposited paint particles and the effort to handle them. The use of accurate numerical methods in this process helps to optimize the application process, reduce the number of expensive field experiments, and shortens the development cycle of new vehicles, which ensures predictability of production costs.

Noise reduction is generally accomplished by applying appropriate noise control treatments at strategic locations. Noise control treatments consisting of poroelastic materials in layers are extensively used in noise control products. Sound propagation through poroelastic materials is governed by macroscopic material and geometric properties. Thus, a knowledge of material properties is important to improve the acoustical performance of the resulting noise control products. Since the direct measurement of these properties is cumbersome, these have been usually estimated indirectly from easily measurable acoustic performance metrics such as normal incidence sound transmission and/or absorption coefficient, measured using readily available impedance tube. The existing inverse characterization approaches fulfilled the estimation by curve fitting measured and predicted acoustic models.

FMVSS No. 205, “Glazing Materials,” uses impact test methods specified in ANSI/SAE Z26.1-1996. NHTSA’s Vehicle Research and Test Center initiated research to evaluate a subset of test methods from ANSI Z26.1-1996 including the 227 gram ball and shot bag impact tests, and the fracture test. Additional research was completed to learn about potential changes to tempered glass strength due to the ceramic paint area (CPA), and to compare the performance of twelve by twelve inch flat samples and full-size production parts. Glass evaluated included tempered rear quarter, sunroof, and backlight glazing. Samples with a paint edge were compared to samples without paint, and to production parts with and without paint in equivalent impact tests. A modified shot bag with stiffened sidewalls was compared to the ANSI standard shot bag. The fracture test comparison included evaluating the ANSI Z26.1 impact location and ECE R43 impact location.

The world is on a “take-make-waste,” linear-growth economic trajectory where products are bought, used, and then discarded in direct progression with little to no consideration for recycling or reuse. This unsustainable path now requires an urgent call to action for all sectors in the global society: circularity is a must to restore the health of the planet and people. However, carbon-rich textile waste could potentially become a next-generation feedstock, and the mobility sector has the capacity to mobilize ecologically minded designs, supply chains, financing mechanisms, consumer education, cross-sector activation, and more to capitalize on this “new source of carbon.” Activating textile circularity will be one of the biggest business opportunities to drive top- and bottom-line growth for the mobility industry.

Curbs are as key to automated driving system (ADS) navigation, operation, and safety as they are for human driven vehicles. The design, maintenance, and management of curbs and adjacent infrastructure can make the difference in whether ADS vehicles can pick up and deliver passengers and goods safely, efficiently, and effectively. Curbs may also be key to integrating ADS services with other forms of active and human-driven transportation. Benefits from accessibility, reduced emissions, and strong supply chains require that ADS vehicles be able to dock curbside in a manner that does not disrupt traffic or impede safe movement of people walking, biking, or using a mobility device. Automated Vehicles and Infrastructure Enablers: Curbs and Curbside Management addresses considerations regarding the curb with respect to pick up and drops for passengers and freight, as well as managing and designing both sides of the curb with respect to automated vehicles and other types of shared mobility.

The automobile is undergoing the biggest transformation of its 100-year history. Motivated by consumer desire for automobiles to integrate with their digital life and inspired by new electric vehicles (EVs) that routinely receive over-the-air software updates, traditional automakers are embarking on a journey to re-engineer the vehicle as a platform defined by software. The foundation of the shift is a complete re-design from a mechanical hardware-centric system to a cloud-connected, software-centric ecosystem where each function is executed via a service-oriented architecture. This is the basis of the software-defined vehicle (SDV). The Software-defined Vehicle and its Engineering Evolution: Balancing Issues and Challenges in a New Paradigm of Product Development examines the complex journey ahead for traditional manufacturers as they transition to this new software-defined system.

The safety of commercial aviation industry has come under extensive scrutiny and how the system safety process is applied. One specific system safety regulation concerns how unsafe system operating conditions are meeting regulatory requirements. Minimal regulatory guidance was available on this topic and an industry committee (American Society for Testing of Materials) decided to provide a consensus standard with input from a cross-section of airplane manufacturers, suppliers, and regulatory authorities on what is meant by an unsafe system operating condition and how compliance can be shown to the regulation(s). The committee determined that an unsafe system operating condition is when a failure condition severity increases (to hazardous or catastrophic) due to crewmember(s) inaction. For example, if a hazard has occurred it is possible the severity can increase to an unacceptable level as the crewmember(s) are not aware of the hazard.

The limitations of commonly used materials such as steel in withstanding high temperatures led to exploring alternative alloys. For instance, Inconel 825 is a nickel-based alloy known for its exceptional corrosion resistance. Thus, the Inconel 825 is used in various applications, including aerospace, marine propulsion, and missiles. Though it has many advantages, machining this alloy at high temperatures could be challenging due to its inadequate heat conductivity, increased strain hardening propensity, and extreme dynamic shear strength. The resultant hardened chips generated during high-speed machining exhibit elevated temperatures, leading to tool wear and surface damage, extending into the subsurface. This work investigated the influence of varying process settings on the machinability of Inconel 825 metal, using both uncoated and coated tools.

Using dc magnetron sputtering, Al/Si films were made on surfaces made of fused quartz and silicon. It was carefully controlled that the films contained no more than 7 at.% silicon under ideal deposition conditions. This was done by changing the target's structure and adding silicon lines to it. This had to be done to get a good reading on how much silicon was in the plates. After being heated to 800°C and then cooled in very cold water, the thermo-elastic face-centered cubic structure changed into the flat crush test martensite. In Al/Si films with a Si content of 25.6%, this change took place. It looks like the shift in the opposite way was also thermoelastic. The several thermoelastic transitions that happened were caused by changes in temperature. Some Al-36 at.% Si coatings that were scraped off of a quartz substrate showed shape memory qualities when heated after being deformed. The coverings on these things were warped.

Magnesium and its alloys are promising engineering materials with broad potential applications in the automotive, aerospace, and biomedical fields. These materials are prized for their lightweight properties, impressive specific strength, and biocompatibility. However, their practical use is often hindered by their low wear and corrosion resistance. Despite their excellent mechanical properties, the high strength-to-weight ratio of magnesium alloys necessitates surface protection for many applications. In this particular study, we employed the plasma spraying technique to enhance the low corrosion resistance of the AZ91D magnesium alloy. We conducted a wear analysis on nine coated samples, each with a thickness of 6mm, to assess their tribological performance. To evaluate the surface morphology and microstructure of the dual-phase treated samples, we employed scanning electron microscopy (SEM) and X-ray diffraction (XRD).

The ferrous deuteroporphyrin cast Fe alloy and nickel-coated steel were lap welded successfully using the mechanical stir welding process. It was able to weld junctions with full strength and fracture on the base metal side of nickel-coated steel during the welding process, but ferrous alloy and nickel steel could not be welded together. It was proposed that the joining technique and function of the Ni coating be used in the friction stir lap welding of Ni-coated steel and aluminum alloy. The Ni coating improved both the weldability of iron and steel, resulting in the production of a Fe-Ni eutectic structure with a low melting point at the interface of the two materials. It is possible to successfully fuse steel and ferrous metals together.

Metal matrix composite processing allows the possibility of improving both mechanical and damping properties by selecting reinforcements which have high damping characteristics, hardness and strength. In this work, the effect of disperse SiC as passive agents on the dynamic properties such as damping ratio, loss factor and effect of damping factor on Al7075/Al2O3/SiC composite machinability was studied. The composite samples were fabricated as Al7075/5%Al2O3, Al7075/5%Al2O3/5%SiC, Al7075/5%Al2O3/10%SiC and Al7075/5%Al2O3/15%SiC as well subsequently experimented. The dynamic properties were found using free vibration test approach and the hysteresis loop method. Further, the machinability in end milling operation was accessed by experimentation with the surface finish as the parameter under scrutiny. The composite Al7075/5%Al2O3/5%SiC has better damping ratio comparing to others, also the composite with the best damping capacity produces a fine surface finish during machining.

This study focuses on enhancing the corrosion resistance of AZ91D magnesium alloy, known for its impressive strength-to-weight ratio within the magnesium group. Despite its lightweight properties, the alloy's moderate corrosion and wear resistance have restricted its widespread use. To address this limitation, we explored the application of the Dow 17 process to enable hard anodizing of AZ91D magnesium alloy. Our primary objective is to investigate the impact of hard anodizing on AZ91D magnesium alloy and its potential to mitigate corrosion issues. Hard anodizing results in the formation of a robust oxide film on the alloy's surface. We posit that this oxide film can significantly reduce substrate corrosion, expanding the alloy's utility in various applications. To substantiate our claims, we conducted a comprehensive corrosion performance analysis of AZ91D magnesium alloy, with and without hard anodizing treatment.

The current research focuses on enhancing the performance of Si solar cells by using Er2O3 (Erbium Oxide) in cubic crystalline nature serves as an anti-reflection coating material. An anti-reflective coating aims to improve the Efficient Power Conversion (EPC) of polycrystalline silicon wafers solar cells (PSSC) utilised in solar roof panels of the automotive sector. It also exhibits superior light transmittance and least light reflectance, which eventually leads to the increase EPC. Erbium oxide helps to convert low energy photons into high energy photons. The incident photons, which lies on the solar cell, gradually losses its energy to travel in a denser medium and dissipate in the form of heat energy. In order to overcome the rate of reflection, current research aims in synthesis of erbium oxide nanosheets using electrospinning deposition technique for varying deposition timings such as 1, 1.5 and 2 hours.

Aluminium alloys enrolled their applications in automobile sectors, agricultural equipment, machine tools and aerospace because of their weight-to-strength ratio. Aluminium alloy 7075-T651 is an inevitable material used in engineering sectors. Turning is a metal removal process, to obtain net geometrical aspects and better surface finish of the products. The machinability of the turning operation is based on different factors; however, turning factors and material of tool plays a significant position in the turning process. To identify the truthful cutting parameters to achieve multi-responses in turning operation, the experiment was designed via Response Surface Methodology (RSM) Central Composite Design (CCD) and the experimental results are analyzed under the desirability approach.