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Although structural intensity was introduced in the 80's, this concept never found practical applications, neither for numerical nor experimental approaches. Quickly, it has been pointed out that only the irrotational component of the intensity offers an easy interpretation of the dynamic behavior of structures by visualizing the vibration energy flow. This is especially valuable at mid and high frequency where the structure response understanding can be challenging. A new methodolodgy is proposed in order to extract this irrotational intensity field from the Finite Element Model of assembled structures such as Bodies In White. This methodology is hybrid in the sense that it employs two distinct solvers: a dynamic solver to compute the structural dynamic response and a thermal solver to address a diffusion equation analogous to the thermal conduction built from the previous dynamic response.

Passengers perceive annoying noise significantly stronger for electric vehicle, as an e-motor is in the absence of background noise, such as traditional powertrain noise. Automotive body coating squeak noise is becoming the most annoying noise for customers. It is a high-frequency noise that is attributed to the viscoelastic property of electrophoretic painting. The reason behind of this complex phenomenon lies in several aspects, so the solving solutions are also varying. Previous studies often focused to analyze the root cause of body squeaks through finite element analysis of body-in-white (BIW) opening diagonal distortion, as well as welding spots distribution. This paper first attempts to address it with the Maxwell viscoelastic model to describe the physical phenomenon. The model is composed of Maxwell element, a linear spring and a nonlinear dashpot to simulate the dynamic mechanical behavior of vehicle body coating when encountering vibration.

This specification covers a magnesium alloy in the form of welding wire (see 8.5).

This specification covers a magnesium alloy in the form of welding wire (see 8.5).

This specification covers a magnesium alloy in the form of welding wire (see 8.5).

This specification covers a magnesium alloy in the form of welding wire (see 8.5).

This specification covers a magnesium alloy in the form of welding wire (see 8.6).

This specification covers a magnesium alloy in the form of welding wire (see 8.5).

This specification covers a magnesium alloy in the form of welding wire (see 8.5).

This specification covers a magnesium alloy in the form of welding wire (see 8.6).

With the advent of this new era of electric-driven automobiles, the simulation and virtual digital twin modeling world is now embarking on new sets of challenges. Getting key insights into electric motor behavior has a significant impact on the net output and range of electric vehicles. In this paper, a complete 3D CFD model of an Electric Motor is developed to understand its churning losses at different operating speeds. The simulation study details how the flow field develops inside this electric motor at different operating speeds and oil temperatures. The contributions of the crown and weld endrings, crown and weld end-windings, and airgap to the net churning loss are also analyzed. The oil distribution patterns on the end-windings show the effect of the centrifugal effect in scrapping oil from the inner structures at higher speeds. Also, the effect of the sump height with higher operating speeds are also analyzed.

The electrification of vehicles marks the introduction of new products to the automotive market and a continued effort to optimize their performance. The electric motor is an important component with which a further optimization of efficiency, power density and cost can be achieved. Additional benefits can be realized in the laminated core. This paper presents an innovative method to produce laminated stacks by a chain of processes different from conventional ways. The process chain presents a sequence of precision blanking, buffering, heat treatment and gluing. The effect of these processes is compared with existing solutions that typically contain some individual features but usually not the combination that enhances the overall effect. The heat treatment decreases residual stresses from previous process steps and reduces power losses in the laminated core. Depending on the design, benefits around 20% are found.

This study deals with the fatigue life prediction methodology of welding simulation components involving arc welding. First, a method for deriving the cyclic deformation and fatigue properties of the weld metal (that is also called ER70S-3 in AWS, American Welding Standard) is explained using solid bar specimens. Then, welded tube specimens were used with two symmetric welds and subjected to axial, torsion, and combined in-phase and out-of-phase axial-torsion loads. In most previous studies the weld bead’s start/stop were arbitrarily removed by overlapping the starting and stop point. Because it can reduce fatigue data scatter. However, in this study make the two symmetric weld’s start/stops exposed to applying load. Because the shape of the weld bead generated after the welding process can act as a notch (Ex. root notch at weld start / Crater at weld stop) to an applied stress. Accordingly, they were intentionally designed to cause stress concentrations on start/stops.

A special spot weld element (SWE) is presented for simplified representation of spot joints in complex structures for structural durability evaluation using the mesh-insensitive structural stress method. The SWE is formulated using rigorous linear four-node Mindlin shell elements with consideration of weld region kinematic constraints and force/moments equilibrium conditions. The SWEs are capable of capturing all major deformation modes around weld region such that rather coarse finite element mesh can be used in durability modeling of complex vehicle structures without losing any accuracy. With the SWEs, all relevant traction structural stress components around a spot weld nugget can be fully captured in a mesh-insensitive manner for evaluation of multiaxial fatigue failure.

The design of lightweight vehicle structures has become a common method for automotive manufacturers to increase fuel efficiency and decrease carbon emission of their products. By using aluminum instead of steel, manufacturers can reduce the weight of a vehicle while still maintaining the required strength and stiffness. Currently, Resistance Spot Welding (RSW) is used extensively to join steel body panels but presents challenges when applied to aluminum. When compared to steel, RSW of aluminum requires frequent electrode cleaning, higher energy usage, and more controlled welding parameters, which has driven up the cost of manufacturing. Due to the increased cost associated with RSW of aluminum, Refill Friction Stir Spot Welding (RFSSW) is being considered as an alternative to RSW for joining aluminum body panels. RFSSW consumes less energy, requires less maintenance, and produces more consistent welding in aluminum as compared to RSW.

A multi-material design strategy of steel and aluminium alloy is a key solution in response to stringent emission requirements and to offset the additional weight of batteries in electric vehicles. However, dissimilar Al/steel welding is mainly challenging due to the formation of brittle and hard intermetallic compounds (IMC). In order to resolve the issue of IMC formation, the present study proposed an alternative manufacturing method consisting of friction surfacing deposition and arc welding. The proposed method involves two steps for dissimilar welding: step 1, friction surfacing deposition of aluminium alloy on the steel surface and step 2, arc welding of friction surfacing deposited steel and aluminium alloy.

Automotive body structures are being increasingly made in multi-material system consisting of steel, aluminum (Al) and fiber-reinforced plastics (FRP). Therefore, many joining techniques such as self-piercing riveting (SPR) and adhesive bonding have been developed. On the other hand, OEMs want to minimize the number of joining techniques to reduce the manufacturing complexity. Amount all joining methods, resistance spot welding (RSW) is the most advanced and cost-effective one for body-in-white. However, RSW cannot be applied for joining dissimilar materials. Therefore, a novel Rivet Resistance Spot Welding method (RRSW) was developed in which Al or FRP components can be directly welded to steel structures with existing welding systems. RRSW uses rivet-like double T-shaped steel elements as a welding adapter which are formed or integrated into Al or FRP components during their forming process. After that, they are welded to the steel components by RSW.

Battery packs of electric vehicles are typically composed of lithium-ion batteries with aluminum and copper acting as cell terminals. These terminals are joined together in series by means of connector tabs to produce sufficient power and energy output. Such critical electrical and structural cell terminal connections involve several challenges when joining thin, highly reflective and dissimilar materials with widely differing thermo-mechanical properties. This may involve potential deformation during the joining process and the formation of brittle intermetallic compounds that reduce conductivity and deteriorate mechanical properties. Among various joining techniques, laser welding has demonstrated significant advantages, including the capability to produce joints with low electrical contact resistance and high mechanical strength, along with high precision required for delicate materials like aluminum and copper.

The rotor and stator of electric motors consist of multiple materials, of which steel forms the majority of mass and volume. Steel in electric motors is commonly in the form of thin sheets (laminations), stacked along the axis of the rotor. The structural integrity of such a stack can be ensured using bolting, welding or bonding of the laminations. Predictive mechanical finite element simulations of these laminated stacks can become computationally intense because the steel sheets are thin, and the motor often contains hundreds of them. If the laminations are modelled individually, the size of the elements is very small compared to the overall dimensions and the interface between the laminations need to be modelled as well. In this paper, we present an alternate method of modelling this laminated stack as a single solid body using homogeneous and orthotropic material property, instead of representing each lamination.

This specification covers a nickel in the form of round wire and rectangular ribbon.