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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 purpose of the theme developed in this work is to increase the volume of information related to vehicle evaluation and how human perception can be translated into numbers, thus facilitating the process of definitions, refinement and analysis of its performance. Based on the discipline of psychophysics, where it is possible to study the relationship between stimulus and sensation and the use of post processing tool known as PSD (Power Spectral Density), post process the acceleration data of inputs perceived by the occupants of the vehicle, when driving in routes considered ergodic. By this, in a summarized way, get to human subjective perception of comfort. This material shows in a conceptual way a sequence of studies that were conducted to make it possible, to generate a performance classification of the subjective vehicle attribute of Smoothness, by processing values of acceleration measured the driver's seat.

Vehicle ergonomics, more specifically driver ergonomics, has been the subject of interest in the automotive industry as a way to provide customers vehicles that have more than modern project, efficiency and competitive price. The driver ergonomics is related to the way the driver interacts with the vehicle interior, particularly, with the seat, hand and foot controls, considering aspects such as ease of access, space, proper upper and lower limb motion and drivers comfort and fatigue. Regarding the lower limbs, the driver’s comfort can be evaluated in terms of joint moments and muscle forces, which are influenced by the hip, knee and ankle joint angles, which in turn depend on the distances between the seat and pedal. Variations in seat to pedal horizontal or vertical distances will result in different angular positions and, consequently, different joint moments and muscle forces, which are associated to greater or lower muscular activations and greater or lower driver’s fatigue.

Vehicular manual transmissions systems often use a vent or breather to allow pressure control inside the main structure. This pressure variation comes along with differences caused by working temperature range. However along with air flow these vents may occasionally allow oil passage noticed by vehicle owner as a transmission leakage event. The more sophisticated the more expensive is the venting device which may contain membranes, labyrinths, baffles and other solutions to avoid leakage. The purpose of this paper is to present a simplified solution to avoid transmission fluid leakage by combining a regular sealing device (fiber concept gasket) and a baffle to avoid oil splash to reach the venting device. The proposed concept took into consideration a quick implementation aspect, low financial impact and less complexity to the overall current system modifying an existing component by adding secondary function instead of creating additional components.

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 work conducted an optimization in sheet metal blank's sizes for cold pressing automotive parts, comparing dimensional characteristics of automotive hood outer panels deep drawn with commonly used blank sizes for this process. As a result, it was possible to suggest modifications to smaller blank sizes, accordingly to the improvement accomplished in this work. The experimental study was conducted from observations in part's superficial aspects after its deep drawing process, which was realized in a commonly used tooling for automotive industry, with a blank's width reduction for the suggested case. The results showed a cost reduction opportunity based in this optimization.

The growing need to avoid failures in vehicle components have become the methods of quality control of manufacturing processes more efficient and accurate, especially in safety components like automotive wheels. The aim of this work is examines the efficiency of aluminum-silicon specifications related to wheel quality for avoiding the poor results obtained in impact and fatigue tests as result of improper settings in the chemical composition and manufacture process. It is evaluated mainly the content of magnesium in aluminum alloys and certified the correct degree of silicon modification in the microstructure on the performance of these wheels. The test results indicate that even with the chemical composition parameters specified by the standard, the technical validation of the product may not be adequate.

In the last decades, there has been an increasing demand for vehicle noise control and, at the same time, fuel economy has become critical for the automotive industry. Therefore, a precise balance between performance and mass of sound package components is essential. In this work the original dash insulation system of an automotive vehicle was replaced by a lightweight alternative. The methodology of Statistical Energy Analysis (SEA) was employed to design multilayered fibrous constructions for engine noise control. The results were verified through experimental testing and supported the achievement of vehicle requirements regarding comfort, weight and environment.

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 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.

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.