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Multiple experimental studies were performed on galling intiation for variety of tooling materials, coatings and surface treatments, sheet materials with various surface textures and lubrication. Majority of studies were performed for small number of samples in laboratory conditions. In this paper, the methodology of screening experiment using different combinations of tooling configurations and sheet material in the lab followed by the high volume small scale U-bend performed in the progressive die on the mechanical press is discussed. The experimental study was performed to understand the effect of the interface between the sheet metal and the die surface on sheet metal flow during stamping operations. Aluminum sheet AA5754 2.5mm thick was used in this experimentation. The sheet was tested in laboratory conditions by pulling between two flat insert with controllable clamping force and through the drawbead system with variable radii of the female bead.

Roller offsetting is an incremental forming technique used to generate offset stiffening or mating features in sheet metal parts. Compared to die forming, roller offsetting utilizes generic tooling to create versatile designs at a relatively lower forming speed, making it well-suited for low volume productions in automotive and other industries. However, more significant distortion can be generated from roller offset forming process resulting from springback after forming. In this work, we use particle swarm optimization to identify the tool path and resulting feature geometry that minimizes distortion. In our approach, time-dependent finite element simulations are adopted to predict the distortion of each candidate tool path using a quarter symmetry model of the part. A multi-objective fitness function is used to both minimize the distortion measure while constraining the minimal radius of curvature in the tool path.

Off-roading is the scenario of driving a vehicle on unpaved surfaces such as sand, gravel, riverbeds, rocks, and other natural terrain. Vehicle designed for that purpose requires jumping from height due to uneven surfaces/patches. This also requires them to sustain a high amount of loads acting upon them on impact. Thus, off-roading vehicles should not only provide intended vehicle dynamics performance but at the same time should be durable as well. Drop test which is done in a controlled environment is a widely used method to validate the durability of vehicle in such scenarios wherein the vehicle is dropped from a certain predefined height. In Multibody dynamics simulation, drop test was replicated and acceleration data computed at different locations in the vehicle were correlated with actual physical test data. Correlation was done for different drop heights. This paper presents relevant details of the virtual vehicle modeling, loadcase, test data & subsequent correlation.

Fiber-reinforced plastics (FRPs), produced through injection molding, are increasingly preferred over steel in automotive applications due to their lightweight, moldability, and excellent physical properties. However, the expanding use of FRPs presents a critical challenge: deformation stability. The occurrence of warping significantly compromises the initial product quality due to challenges in part mounting and interference with surrounding parts. Consequently, mitigating warpage in FRP-based injection parts is paramount for achieving high-quality parts. In this study, we present a holistic approach to address warpage in injection-molded parts using FRP. We employed a systematic Design of Experiments (DOE) methodology to optimize materials, processes, and equipment, with a focus on reducing warpage, particularly for the exterior part. First, we optimized material using a mixture design in DOE, emphasizing reinforcements favorable for warpage mitigation.

Soft magnetic cores of electric motors and generators are normally manufactured by stamping individual circular laminates from non-oriented electrical steel (NOES) sheets and stacking them layer by layer to reach the required height. The traditional lamination method can only achieve the average performance of the NOES since the magnetization is in all the directions of the sheet plane. Although NOES is ideal to have isotropic magnetic properties in all the directions of the sheet plane, commercially available electrical steel sheets always show apparent anisotropy in the rotating magnetization directions lying in the sheet plane. The anisotropy in magnetic properties not only causes fluctuations in the rotating magnetic field, but also leads to oscillations in electromagnetic torque, and thus needs to be minimized.

Certain sports utility vehicles (SUVs) utilize dual latches and gas struts in their hood design. This is primarily driven by the larger size of the hood and specific architectural requirements. These hoods can be securely latched either by a dynamic single stroke closing method or by quasistatic two stroke closing method. In dynamic method, the hood is closed with a single, high-velocity motion for the final primary latching, whereas in quasistatic method, force is initially applied for the secondary latching and then for the final primary latching. In this study, both the dynamic and quasistatic closing methods are compared in terms of closing force and velocity and hood over travel distance. A load cell is used for measuring the closing force, velocity meter is used for velocity measurement and a rope sensor is used for measuring the hood over travel distance.

This paper reviews the current situation in the development of accelerated testing of automotive engineering, consisting of the four following areas: 1. Field testing of the natural product. 2. Additional technology of separate testing in the laboratory on the basis of physical simulation of separate field conditions using corresponding methods and equipment separately and conducting: safety testing, special programs of testing using digital simulation, special testing with changing certain parameters of environment, corrosion testing, etc. Both of the traditional testing developments above can be found in many magazines, journals, conferences, presentations, and proceedings. 3. Testing on the basis of digital (computer) simulation of product and/or field conditions. This area of testing has been developed in the last dozen years. Many articles and presentations were published during this time. 4.

Validation of powertrain systems is nowadays performed with specific durability relevant load cycles, which represent the lifetime requirement of individual powertrain components. The definition of such durability relevant load cycles, which are used for vehicle testing should ideally be based on the actual vehicle's usage. Recording driving cycles within a vehicle is one of the most typical ways of collecting vehicle usage and relevant end customer behavior, but the generation of such measured vehicle data can be time consuming. In addition, this method of capturing on-road measurements has limitations in the variation of vehicle loadings (e.g., number of passengers, luggage, trailer usage etc.). Especially for new applications, entering new target markets, these kinds of in-vehicle measurements are not possible in early development stages, as the required vehicle or powertrain configuration is not available in hardware or incapable of measurements.

Often, when assessing the distraction or ease of use of an in-vehicle task (such as entering a destination using the street address method), the first question is “How long does the task take on average?” Engineers routinely resolve this question using computational models. For in-vehicle tasks, “how long” is estimated by summing times for the included task elements (e.g., decide what to do, press a button) from SAE Recommended Practice J2365 or now using new static (while parked) data presented here. Times for the occlusion conditions in J2365 and the NHTSA Distraction Guidelines can be determined using static data and Pettitt’s Method or Purucker’s Method. These first approximations are reasonable and can be determined quickly. The next question usually is “How likely is it that the task will exceed some limit?”

Motorcycles which are designed for both regular as well as rough terrains experience more severe vertical impact loads from ground in comparison with motorcycles which travel only on regular terrains. Therefore, drop test is considered an important method to evaluate durability for said vehicles. Fuel Tank mounted over front frame of a motorcycle is the most critical component from safety point of view and hence, need to be analysed for vertical drop load case. To do so, modelling of whole vehicle can be a hectic task and has to be avoided. In the present work, behaviour of fuel tank mounted over frame support and subjected to vertical drop from H(m) height is studied with the help of support excitation method incorporated with explicit non-linear time integration scheme using Finite Element Analysis (FEA) code in commercial FEA software. Through this scheme, effect on Fuel Tank of vehicle drop can be studied without actually modelling the whole vehicle.

In alignment with the U.S. Army's Climate Strategy and the broader trend in automotive technology, there is a strategic shift towards electrification and hybridization of the vehicle fleet. While a major goal of this effort is to mitigate the carbon footprint of the U.S. Army's vehicle operations, this transition also presents an opportunity to harness advancements in automotive electrification. Among the key vehicles in focus are tactical wheeled vehicles, which provide military forces with versatile and rugged transportation solutions for various combat scenarios, ensuring mobility, protection, and adaptability on the battlefield. This study investigates the potential of electrified tactical wheeled vehicles by conducting a survey involving a diverse group of vehicle operators across various ranks within the U.S. Army.

At the dawn of battery electric vehicles (BEVs), protection of automotive battery systems as well as passengers, especially from severe side impact, has become one of the latest and most challenging topics in the BEV crashworthiness designs. Accordingly, two material-selection concepts are being justified by the automotive industry: either heavy-gauge extruded aluminum alloys or light-gauge advanced high-strength steels (AHSSs) shall be the optimal materials to fabricate the reinforcement structures to satisfy both the safety and lightweight requirements. In the meantime, such a justification also motivated an ongoing C-STARTM (Cliffs Steel Tube as Reinforcement) Protection project, in which a series of modularized steel tube assemblies, were demonstrated to be more cost-efficient, sustainable, design-flexible, and manufacturable than the equivalent extruded aluminum alloy beams as BEV reinforcement structures.

A fundamental study on the ductility of high strength steels in crash deformation is carried out to investigate the effect of the local ductility of various materials on automobile crashworthiness, considering the prestrain induced by press forming in the manufacturing process. In this study, a newly developed 980 MPa-grade steels [1], ‘jetQTM’, is investigated to clarify its advantage in term of crashworthiness in comparison with the conventional DP (Dual Phase) and TRIP steels. Quasi-static axial crushing tests are performed to evaluate the crashworthiness of the different types of steel. Based on the experimental results, the effect of the local ductility of high-strength steel on the risk of material fracture is discussed. In this paper, a new bending test method, orthogonally reverse bending, (ORB), is proposed to simulate the fracture that occurs during crash deformation considering press-forming strain.

Fracturing in a tight radius during bending is one of the major manufacturing issues in forming Advanced High Strength Steels (AHSS). The study investigated the bendability of AHSS under two forming conditions: bending with and without stretched over the die radius. The bendability was evaluated by conducting modified Bending Under Tension (BUT) test for stretch bending and 90o v bend test for bending without stretch. The study also examined the effect of material properties on the limiting bend ratio. Various strength high strength steels, range from 420 MPa to 1700 MPa tensile strength, were selected in the study. Results indicated that critical radius-to-thickness ratios between the two tests are different but correlated in a relationship which was depicted in the bendability diagram.

Due to the expense and time commitment associated with extensive product testing, vehicle manufacturers are developing new simulation techniques to verify vehicle component performance with less testing and more confidence in the final product. Battery lifetime is of particular difficulty to predict, since each battery is different and there are many different control scenarios that could be implemented based on the specific requirements of each battery type. In order to solve this problem for a 12V auxiliary lead-acid battery, a battery durability analysis model has been previously adapted from lithium-ion applications, which is capable of verifying the impact of lead-acid battery durability in a short period of time. In this study, calibration tools for this model were developed and are presented here, and durability analysis and verification are performed for the application of new electric vehicles.

This specification covers an aluminum alloy in the form of extruded bars, rods, and profiles 0.250 to 2.000 inches (6.35 to 50.80 mm) in nominal thickness and up to 32 square inches (206 cm2), inclusive, in cross-sectional area (see 8.5).

This specification covers an aluminum alloy in the form of extruded bars, rods, wire, profiles, and tubing, flash-welded rings fabricated from extruded stock, and stock for flash-welded rings (see 8.6).

This specification covers an aluminum alloy in the form of extruded bars, rods, wire, shapes, and tubing 5.000 inches (127.00 mm) and under in nominal diameter or least thickness (wall thickness of tubing) (see 8.5).