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The current study shows interesting results obtained by a new virtual approaching for evaluating the final stresses presented in automotive components during its application in vehicle which suggests product engineers a new tool for measuring the residual stresses in casting. As part of this proposal, an automotive as-cast aluminum wheel belong to current production was evaluated in accordance with data acquired in its manufacturing process. At that step, it was taking into account the real information of casting process parameters and the metallurgic results obtained in laboratorial tests such as, metallographic, chemical and mechanical tests. FEA (Finite Element Analysis) on simulation of wheel loading stress was made regarding those preliminary data obtained in CRSFEA simulation (cast residual stress finite element analysis) as entered parameters.

The definition of the ride attribute is very difficult because it is part of human perception during driving. For vehicle dynamics work, have details of what is good or what is bad considering driving comfort, usually, induces some controversial opinions. In this work, the use of a single accelerometer is shown as a tool to characterize the basic vehicle vibrational behavior and so support the correlation between human perception and the resulting ride comfort presented. By using PSD theory, it is possible to “see” how the vehicle vibrates and so have a better understanding of where in the vehicle is located a possible issue and how to fix it. In a more advanced point of view is possible to characterize each vehicle with a ride “personality”, this meaning how each brand and model behave and so how vehicle behave to the consumer approve or complain about it..

This paper explores the method of modeling and validation the computational tools able to accurately replicate the dynamic behavior of a Formula SAE vehicle. Based on limitations in conducting physical tests, it is possible to mathematically predict the forces and momentum generated on the steering column of the vehicle, minimizing effort and improving driver comfort even before the component physically manufactured. The results in permanent state due technical instrumentations were used in the physical vehicles and compared with other proposals (skid Pad test). As the software simulating the same path, it was possible to adopt values of speed and wheel steering, allowing compare the dynamics of the vehicle, through the signals from other sensors installed in the data acquisition system, validating the behavior of the models presented in permanent state. Other aspects were studied to understand vehicle behavior concerning lateral stability and steering behavior.

This work presents aspects related to research and development of high-speed steels for valve seat inserts application. Five series of materials were evaluated: high speed steel M3/2 infiltrated with copper during sintering; high speed steel M3/2 with Cu3P addition; high speed steel M3/2 with Cu3P addition and further copper infiltrated during sintering; high speed steel M3/2 mixed with iron powder; high speed steel M3/2 mixed with iron powder and niobium carbide. The physical and mechanical properties of the evaluated high-speed steels are presented in terms of densification, hardness, and radial mechanical strength. These properties are compared according to the materials processing and heat treatment.

The current study shows important results obtained by a new technique of residual stress virtual evaluation in automotive components for improving the development and quality of new products, aiming the structural performance, mass and cost reductions. The approaching those virtual results were adjusted by metallurgic data obtained in metallography, mechanical and chemical analysis. As part of this proposal, an automotive aluminum wheel belong to current production was evaluated in accordance with data acquired in the wheel manufacturing process. It was taking in account the real information of casting process parameters and the metallurgic information obtained in laboratorial tests. In this work, the results show that product residual stresses shall be considerate and evaluated during design phases as improving proposal, new technical concerns and quality improving.

The application of press hardening steels (PHS) Al-Si coating has been increasing in body in white vehicles as an approach to meet the demands of safety and CO2 reduction regulations. The vehicle structures with PHS largely depend on the integrity and the mechanical performance of the spots weld. During the spot welding process, intermetallic phase may appear in function of the chemical composition of the steel and coating. One of these intermetallics is the Fe-Al phase which brittleness decreases the strength of the weld joint. In this study, resistance spot welding (RSW) experiments were performed in order to evaluate the influence of the welding parameters of single-lap joints PHS - 22MnB5 steel grade.

The current study proposes to approach the fatigue behavior of stabilizer bars and specimens manufactured in quenched / tempered and as-received SAE5160 steels with and without a surface micro-notch. Some S-N specimens and stabilizer bars were shot-peened to improve the fatigue strength due to creation of compressive surface residue stresses and by surface plastic strain and others samples received a surface micro-notch of 0.3 mm depth introduced by EDM process. The crack growth evaluation at micro-notch was made comparatively with da/dN-ΔK curves in CT specimens. The proposed experimental study consists of comparative analysis of da/dN-ΔK and S-N curves, fractographic and, metallographic analysis, stabilizer bar bench tests, and after that, it is intended to show the relevant aspects of two microstructural classes currently specified for stabilizer bars, the beneficial effects obtained by shot peening and the bad influences of surface micro-notches.

Nowadays, electromagnetic compatibility (EMC) has taken an important role in automotive development. This is because the effects that EMC can cause in a vehicle or on the environment. All systems contained in a vehicle emit EMC, and can be influenced by it also. During the vehicle design phase some variables have to be considered and improved to make the vehicle to be electromagnetic compatible. We can list the vehicle systems as electromagnetic generators or victims, as below: Generators: Ignition GPS transmission system Mobile phone transmission system Electrical motors Radars Power modules Victims: Sensors Cables Control modules (BCM, ECM, etc.) An example of a complete system subject to the EM effects is the X-by-wire (or drive-by-wire) system, where mechanical systems are substituted by modules, cables, sensors, actuators. This system has to be designed considering electromagnetic compatibility.

The current study has the proposal to approach the differences in dynamic behavior between camshaft manufactured in the traditional gray cast iron and an alloyed gray cast iron with the improvement on mechanical properties in order to stresses found on roller finger follower applied systems. The main objective of this paper is to show that camshaft made of modified gray cast iron and heat treated through the remelting process is still a good solution for application with roller finger followers systems which requires higher wear resistance standards. The proposed experimental study consists of comparative analysis of microstructure and hardness, dynamometers tests, dimensional measurements of camshafts, and after that, intends to show the higher performance of this manufacturing process in more severe applications of internal combustion engines.

Using current technologies, a single “entry level” vehicle has millions of electrical signals sent through dozens of modules, sensors and actuators, and those signals can be sent over the air, creating a telemetry data that can be used for several ends. One electrical device is set up to have diagnosis, in order to make maintenance feasible and support repair, plus giving improvement directions for specialists on new developments and specifications, but in several cases the diagnosis can only determine the mechanism of failure, but not the event that triggered that failure. Current evaluation method involves teardown, testing and knowledge from the involved specialized team, but this implies in recovering of failed parts, which in larger automakers with thousands of dealers/repair shops, reduces the sample for analyses when there is a systemic issue with one component.

In the middle of the global competition, inside the automotive sector, the perceived quality of costumers, related to the beauty and harmony of the outer skin surfaces of motor vehicles, has become one of the main determinant factors in the purchase process decision. In general, the initial perceived quality of a car is determined by an appealing design of its body, the color and gloss of its paint, and also the manufacturing and assembly accuracy of the skin panels. The appealing design makes the skin panel even more complex and hard to produce with current metal forming technologies and the results are often small distortions on the outer surfaces about tens of microns and most of the times paint does not cover such imperfections. Despite the technological advances along the years, surface quality inspection was still being performed by manual and subjective evaluation by experts.