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A number of functional and non- functional fillers are invariably used for friction material composites. In recent years disposal of fly ash has been a big challenge due to low availability of damping sites. Current work investigates the characterization of Low -metallic and Organic composites made with fly ash with variable concentrations and evaluated for braking performance (SAE J2522) & wear (SAE J2707) on a brake inertia dynamometer. Composites have been characterized for their physical, thermal, mechanical and tribological performance. Low-metal based composites (LMBC) have shown better thermal resistance than non-ferrous organic formulation based composites (NFOC). Mechanical properties such as hardness, shear strength and compressibility have been found to be similar for both the composites. NFOC composites have shown better wear resistance while acquiring slightly lower coefficient of friction values.

The ever-growing concern to reduce the impact of transportation systems on environment has pushed automotive industry towards fuel-efficient and sustainable solutions. While several approaches have been used to improve fuel efficiency, the light-weighting of automobile components has proven broadly effective. A substantial effort is devoted to lightweighting body-in-white which contributes ~35% of total weight of vehicle. Closure systems, however, have been often overlooked. Closure systems are extremely important as they account for ~ 50% of structural mass and have a very diverse range of requirements, including crash safety, durability, strength, fit, finish, NVH, and weather sealing. To this end, a carbon fiber-reinforced thermoplastic composite door is being designed for an OEM’s mid-size SUV, that enables 42.5% weight reduction. In this work, several novel composite door assembly designs were developed by using an integrated design, analysis and optimization approach.

High surface area particles have drawn attention in the context of noise control due to their good sound absorption performance at low frequencies, which is an advantage compared with more traditional materials. That observation suggests that there is a good potential to use these particles in various scenarios, especially where low frequency noise is the main concern. To facilitate their application, composite materials are formed by dispersing particles within a fiber matrix, thus giving more flexibility in positioning those particles. In this work, a hybrid model that combines a model for limp porous materials and a model of high surface area particles is proposed to describe the acoustic performance of such composites. Two-microphone standing wave tube test results for several types of composites with different thickness, basis weight, and particle concentration are provided.

Friction materials containing metal ingredients used in the automotive industry can cause unfavorable environmental impacts. Existing laws and regulations require heavy metals in brake pads to be phased out of production. Substitutions for metals in friction materials, however, may introduce operational safety issue and other unforeseen problems. In the current study, a molecular dynamics model based on LAMMPS has been developed to study the effect of material composition, density, and geometric configurations on the tribological, mechanical, and thermal properties of silicon carbide under various contact conditions at the atomic level. Simulations which incorporate interfacial contact between surface asperities were performed to predict the elastic modulus, thermal conductivity, wear rate, and coefficient of friction. The resulting predicted properties may help enhance the performance of engineered metal-free friction materials against thermal-mechanical failures.

The emission reduction in gasoline and diesel engines is driving the introduction of systems implementing additives in liquid form: in particular water for injection systems in gasoline engines and urea solutions (AD-blue) in SCR (Selective Catalytic Reduction) systems in diesel engines. Owing to water and AD-Blue can freeze in the car operative temperature range, the tanks must be equipped with heaters to guarantee a sufficient amount of additives in liquid form. Currently used technologies are ceramic PTC (Positive Temperature Coefficient) elements and distributed metal resistors. Ceramic PTC based heaters concentrate all the power in small volumes. They need thermally conductive elements distributing the power over a wide area. The assembly is complex and the cost of the metal parts and related packaging technologies used to insulate the heater from the environment (water or urea) is typically high. Metal resistors are cheaper but must be controlled in current.

Multi-material design is one of the trending methods for automakers to achieve lightweighting cost-efficiently and meet stringent regulations and fuel efficiency concerns. Motivated by this trend, the hybrid single-shot (HSS) process has been recently introduced to manufacture thermoset-thermoplastic composites in one single integrated operation. Although this integration is beneficial in terms of reducing the cycle time, production cost, and manufacturing limitations associated with such hybrid structures, it increases the process complexity due to the simultaneous filling, forming, curing, and bonding actions occurring during the process. To overcome this complexity and have a better understanding on the interaction of these physical events, a quick yet accurate simulation of the HSS process based on an experimentally calibrated numerical approach is presented here to elucidate the effect of different process settings on the final geometry of the hybrid part.

In order to keep the coefficient of friction stable, some additives such as metal sulphides, are included in the brake pads formulation. Previous work from RIMSA has shown that oxidation temperature range of the metal sulphides can be one of the key properties to explain their contribution to the performance and wear of a PAD. This new work is a step forward in the interpretation of the mechanism of sulphides as chemically active additives in the brake pads. Phenolic resin is the matrix of the brake pads and starts to decompose around 300 °C in presence of oxygen and temperature. In order to establish a connection on between sulphide oxidation and phenolic resin degradation, several studies based on heat treatment of blends of different metal sulphides (Iron sulphide, Tin sulphide and Composite sulphide) with phenolic resin have been done. Then the material evolution was studied with techniques such as TGA-DSC, XRD, IR and SEM-EDS.

Recently, keen interest has been focused on the reduction of fuel consumption through the development of eco-friendly and weight-effective vehicles. This is due in part to the strengthening of regulatory standards for fuel efficiency in each country. This study will focus on the optimization of the IP (Instrument Panel) module, in particular, the cowl crossbar, which in some vehicles, can account for more than 33% of the IP module weight. The design objectives of the cowl crossbar were to use continuous fiber thermoplastic composite materials to achieve high stiffness, while optimizing the strength to weight performance as evaluated through vehicle sled and crash testing. This research will introduce the development and optimization methodology for an alternative material, which achieved about a 30% weight reduction as compared to steel.

Corrosion affects all industrial sectors where metals or metal alloys are used in their structures. In the automotive industry, the continuous search for lightweight parts has increased the demand for effective corrosion protection, in order to improve vehicle performance without compromising durability and safety. In this scenario, coatings are essential elements to preserve and protect vehicle parts from various environmental aggressions. Automotive coatings can be classified into primers, topcoats, clearcoats, and specialty coatings. Primers provide corrosion resistance and promote adhesion between the substrate and topcoat. Topcoats provide color, gloss, and durability to the coating system, while clearcoats enhance the appearance and durability of the finish. Specialty coatings provide additional properties, such as scratch resistance, chemical resistance, and UV protection.

Previous work to examine the performance of a variety of control strategies for a switchable damper suspension system is extended to include an adaptive suspension. The aim of this adaptation algorithm is to maintain optimal performance over the wide range of input conditions typically encountered by a vehicle. The adaptive control loop is based on a gain scheduling approach and two strategies are examined both theoretically and experimentally using a quarter vehicle test rig. For the first strategy, the gains are selected on the basis of root mean square (r.m.s.) wheel acceleration measurements whereas in the second approach the r.m.s. value of suspension working space is used. A composite input is used consisting of sections of a road input disturbance of differing levels of magnitude in order to test the control systems' abilities to identify and adapt efficiently as the severity of the road input changes.

This SAE Information Report introduces key concepts and properties of adhesives, sealants, and HTMs and the roles they serve in present-day battery systems applications. The basic chemistry and properties of the three types of materials are summarized along with important health and environmental information. Relevant material dispense methodologies and equipment for material dispensing is reviewed. A series of representative battery applications examples employing adhesives, sealants, and HTMs is also provided with particular attention given to end-use performance.

The global trend on emission reduction is leading to a wider diffusion of SCR systems for diesel engines and to the introduction of WI (water injection) systems in gasoline engines. Cars are equipped with tanks for water and urea solutions (AD-blue). Both liquids can freeze in the car operative temperature range: the tanks must be equipped with heaters to guarantee a sufficient amount of additives in liquid form in any condition. We propose solutions based on plastic PTC (in the following nanoPTC) effect nanomaterials for thermal management of those liquids. The proposed heaters can be molded in any shape, following the specific constraints of each tank, in carpet like shapes for a distributed heating of the tank, or in bulky components integrating sensors housings, pipes, pumping systems or in the packaging of other components. The PTC effect is distributed avoiding overheating in parts with poor thermal exchange (dry condition).

This SAE Recommended Practice provides performance, sampling, certifying requirements, test procedures, and marking requirements for aftermarket wheels intended for normal highway use on passenger cars, light trucks, and multipurpose passenger vehicles. For aftermarket wheels on trailers drawn by passenger cars, light trucks, or multipurpose vehicles, refer to SAE J1204. These performance requirements apply only to wheels made of materials included in Tables 1 and 2. For wheels using composite material, refer to SAE J3204. New nomenclature and terms are added to clarify wheel constructions typically not used in OEM applications. The testing procedures and requirements are based on SAE standards listed in the references.

A novel solution to anti wear-additives is to add relatively small amounts of effective Nano Additives to the main content of lubricants. Such supplement would offer an enhancement to their tribological and thermal properties as wear resistance and friction surface temperature. In this work, different types of Nano additives are used to investigate their effect on the tribological properties of a certain lubricant (TOTAL FLUIDE AT42). Three main Nano additive materials were used with two different concentration for each; Gamma aluminum oxide (Alumina Al2O3), Copper Oxide (CuO) and one-dimensional carbon Nano tubes (CNT). A pin on disc equipment fitted out with circulated lubricant system was operated for 140 hours with normal lubricant, and for 140 hours for each case of the three Nano additives, with a total working time of 980 hours. Weight loss of the pin, friction surface temperature and friction force were measured every 20 working hours.

Earlier publications have demonstrated that pad and disc properties change during storage and also during the SAE J2522 Brake Effectiveness Test Procedure. The current investigation was undertaken to find out how the properties change under milder braking conditions, using the SAE J2707 Wear Test Procedure. A copper-free formulation was selected for the investigation and tested on an inertia dynamometer using a front caliper designed for a passenger car. The pad dynamic modulus changed up or down throughout the test, depending on the test conditions. The pad dynamic modulus, the pad natural frequencies and the disc natural frequencies all decreased by the end of the test. Under high-speed, high-deceleration and high-temperature braking conditions, the pad surface region permanently expands, which results in reduced dynamic modulus and also leads to reduced pad thickness loss as compared with pad weight loss.

A crucial characteristic of composites, which are manufactured from elements of metal, is their mechanical and durability properties. A variety of reinforcing agents and metal nanoparticles are used to create aluminum-based hybrid metal-material composites. These composites are an advantageous alternative for sectors with limited resources because of their robustness, wear resistance, and thermal management capabilities. Manufacturing sectors employ Taguchi optimisation and Grey relational analysis to enhance the mechanical and durability properties of aluminum-based hybrid metal composites. To comprehend the interrelationships between reinforcing materials such as Al2O3 and SiC at constant fly ash concentration, five responses such as wear loss, tensile strength, elongation rate, impact strength, and hardness were considered and assessed. The Grey Relational Analysis (GRA) method is used to optimise these responses and transform them into Grey Relational Grade (GRG).

Abstract Piston internal combustion engines used in the propulsion of ultralight aircraft are characterized by special operating conditions, especially an increased engine oil temperature. Most of the engines intended for the drive of the propeller drivetrain are air cooled. Failure to introduce an additional cooling agent so as to absorb and remove heat from the running engine makes the average lubricating oil temperature rise to about 140°C in the pistohn ring part. With such a thermal load, changes in the moments of resistance to motion of the engine are difficult to determine in the conditions of engine tests due to difficulties in temperature stabilization. The performance of aircraft engines requires taking into account many variables that are difficult to determine, which may affect changes in the moment of resistance to movement of the engine, especially when using oils of low dynamic viscosity.

Traditional manufacturing processes such as injection or compression molding are often enclosed and pressurized systems that produce homogenous products. In contrast, 3D printing is exposed to the environment at ambient (or reduced) temperature and atmospheric pressure. Furthermore, the printing process itself is mostly “layered manufacturing”, i.e., it forms a three-dimensional part by laying down successive layers of materials. Those characteristics inevitably lead to an inconsistent microstructure of 3D printed products and thus cause anisotropic mechanical properties. In this paper, the anisotropic behaviors of 3D printed parts were investigated by using both laboratory coupon specimens (bending specimens) and complex engineering structures (A-pillar). Results show that the orientation of the infills of 3D printed parts can significantly influence their mechanical properties.