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Resistance spot welding is the most common jointing process of parts used in automotive industry. Several methods to represent spot welds are available, and the purpose of this work is to compare two different methods of spot weld modeling through a correlation study, taking into consideration the maximum force withstood by the welded joint, between virtual and lab test results. These spot weld representation methods are beam and solid elements. The tests used in this correlation study load the specimens under pure shear and pure normal forces. And n order to complete this correlation study, the understand of the spot weld failure criteria is also necessary. A soldagem a ponto por resistência é o processo de união de partes mais comum utilizado na indústria automobilística.

Distortion is an intrinsic and undesired effect of the welding process, inducing residual stresses and hence, reducing the fatigue life of the welded structure. This distortion however, does not occurs simultaneously among the entire structure; instead, it occurs gradually during the execution of the welding chord. Due to this, equal structures, but composed by weld chords executed in a different sequencing, presents different residual stresses and therefore, different fatigue performances. This study proposes a method, using finite elements model (CAE), to capture the non-linear distortions of distinct welding sequences and contrast the diverse impacts in fatigue life.

Based on automotive concerns related to global warming, CO2 emissions, safety and fuel efficiency, a trend to use High Strength Steels was stablished in order to meet these concerns and enhance the Body In White (BIW) performance. The usage of Press Hardened Steel (PHS) on the BIW is greatly broadcasted by the automotive industry, however OEMs should consider other important aspects for the vehicle lifecycle, such as repair and serviceability in the occasion of vehicle collision. This paper addresses a repair procedure that meets regular performance characteristics. The study was based on the conditions available on emergent markets dealers to perform an optimized repair. This procedure ensures the proper serviceability of PHS parts on BIW systems and supports the usage of High Strength Steels technology in today’s emergent market vehicles.

Adhesive bonding has gained a lot of popularity on the automotive industry on recent years. The technology has helped OEMs to build lighter vehicles by enabling the joint of dissimilar, lighter materials as well as joints that otherwise could not be welded or bolted together due to the lack of machine and operator access. It has also seen widespread usage to enhance crash performance, due to its ability to distribute stress uniformly and absorb energy. Past test reports had shown that adhesive bonding may have a poor performance when used on Zn-Fe (Galvanneal - GA) coated steel sheets, as the superficial coating layer may delaminate from the base steel, not allowing the adhesive to perform properly. The objective of this paper is to analyze the performance of adhesive bonding on GA coated steels when utilized alongside weld spots.

Nowadays quality and efficiency in the process is no longer a question of competition among automakers. Another factor that has been highlighted in the automotive industry and has become a strategic is the sustainability. Processes considered “green” can generate value for the company with less environmental impact, and they are seen favorably by both market and customers. The process to be examined is widely used by automakers to manufacture their bodies in white, the resistant spot welding process. Considering that, this process generates a considerable impact in the environment mainly for the generation of gases, some manufacturers in recent years has replaced it by the clinching process, which also performs the union of sheet metal, but for metal forming. The process of spot welding generates dust, fumes and pollutants gases, which will be transported to the external environment somehow.

Global automotive companies have heavily invested in the vehicle development in order to provide higher energy efficiency performance to meet the new regulations, and to obtain tax incentives offered by the INOVAR AUTO PROGRAM. One way to improve the vehicle energy efficiency is reducing it mass or apply an optimization. The Body in White (BIW) optimization can be achieved applying aluminum parts, considering the aluminum is a lighter material than the steel, and the BIW is responsible for a significant percentage of the total mass of a vehicle. The Brazilian market to apply the aluminum in the car will face a great challenge, regarding the high vehicle production using aluminum parts. The main challenges are raw materials suppliers to meet the potential demand, the connections between aluminum parts and metal parts, material cost, manufacturing cost, reparability, skilled specialists, etc.

In the vehicle development, part design has a huge influence in its mass, cost and performance. In addition, the part design can be helpful to solve some structure issues such as sheet metal cracks and boom noise, and at the same time achieving the project requirements in performance tests as crash, durability, noise and vibration (N&V) etc. Some design changes as adding reinforcements in the structure and increase the part thickness are largely used by the design engineers. On the other hand, these changes has a great potential for increase mass, cost and affect directly the fuel consumption, which are very sensitive factors for the OEM′s. In order to achieve its target some options may be considered like the use of aluminum or premium material such as Advance High Strength Steel (AHSS) or Pre Hardened Steel (PHS), which has a high cost considering the common sheet metal used in the vehicle structures.